|How to maintain
and repair a boat:
This page updated: December 2011
Troubleshooting / Techniques section
My Boat Engine Maintenance page
My Boat Fiberglass Maintenance page
My Boat Haulout page
My Boat Hull Blisters page
My Boat Painting page
My Climbing The Mast page
My Outboard Motor Maintenance page
My Sail Maintenance page
"If it doesn't move and it should, spray it with WD-40.
If it does move and it shouldn't, wrap it with duct tape."
- Jim and Tim, the Duck Tape Guys
"In theory, there is no difference between theory and practice.
But, in practice, there is."
- Jan L. A. van de Snepscheut, or maybe Chuck Reid ?
Good repair attitudes,
partly from "The Voyager's Handbook" by Beth Leonard
(on Amazon - paid link):
- Be prepared: tools, manuals, parts, knowledge.
- Don't be afraid to tackle a job.
- Check simplest things first. (A simple thing)
- Take your time.
- If you take something major apart, stay organized.
- Don't be afraid to ask for help/advice.
From "Offshore Cruising Encyclopedia" by Steve and Linda Dashew
(on Amazon - paid link):
Basic rules to apply to all repair jobs:
- Don't be afraid to tackle the project.
- Always look for a simple answer to a problem.
- Take your time. [Study the problem, be methodical and systematic, consult manuals and books, don't get frustrated.]
- Only start to disassemble something after all other avenues have been exhausted. [And do it slowly,
labelling pieces, work over a good surface, store pieces carefully.]
- Be very careful about forcing something that's stuck.
- The majority of cruising repairs revolve around electrical problems. ...
When a piece of electrical gear fails, the odds are there's a loose, wet, or dirty connection ...
- Pumps seems to be more maintenance-prone than any other type of gear aboard.
SailNet - Don Casey's "Zen and the Art of Sailboat Maintenance"
SailNet - Kristin Sandvik's "The Best Maintenance is Use"
Chris Caswell's "Maintaining Fiberglass" (misleading title)
Boat Maintenance For (non) Idiots
Nancy Knudsen's "Boat maintenance tips for the frugal sailor"
Periodic Maintenance section of my Lists for Operating a Boat page
... one thing that I have
seen get people into real trouble especially with starting experience as you
have: maintenance, do EVERYTHING yourself. No no no. If you read boating
mags you will CONSTANTLY see the editors advising, let someone else do this
or that. There are many things you can do yourself, but some things that
look simple are, but very dangerous if not done right. I have towed too many
boats in to safety. ... I have just seen so many mishaps from
sailboaters because of the cheap thing. It pays to be thrifty, but sometimes
you absolutely get what you pay for. ...
> What kinds of work would you say should be done by experts, not the owner ?
> Are there some specific areas I should watch out for ?
> I have heard that some boatyard workers may be less competent than a knowledgeable,
> careful and motivated owner. And certainly if you've done the work yourself,
> you are in a better position to redo it or fix it at sea. But you're right;
> trying to do everything yourself probably is a mistake.
I totally agree, for many things, all the workers in the boatyards are not
that competent. I probably would not align a shaft, etc myself. I would use
a boatyard. For other things, there are usually many good independent people
on the waterfront that are far better than the average guy in a boatyard. A
boatyard could not keep my diesel guy for instance, and he can make it on his
own. At the large marine mech. shop that everyone thinks is great, they use
people and kids that are not as sharp or knowledgeable but they charge a
fortune, but pay the worker not too much. I just saw a disaster on a boat
where it was eaten alive. The owner trying to save money, installed the
genset himself. Fine, right up to the time when he was asked why it was not
grounded? He just had a blank look on his face. Now he has a bill and damage
about ten times than he ever expected to pay for anything. I see problems by
people buying cheap batteries. That's why cheap is dangerous sometimes.
Maintenance is one thing, but I don't pretend to be a shipwright, so don't do
anything out of a book that takes a shipwright, or at least let one inspect
as the work is done, and things are still out in the open. Buy the best
batteries, wire, electrical parts, rigging, line, chain, ANYTHING that takes
a major load, or can cost your life. Cheap parts are cheap for a reason. The
best tip I can give anyone is watch a commercial fisherman who depends on the
boat for their living and LIFE. They don't buy anything but the best. Save
money on something else. Buy strong and tough. You will be the one not
"In fact, most home projects are impossible, which is why you should do them yourself.
There is no point in paying other people to screw things up when you can
easily screw them up yourself for far less money."
-- Dave Barry, "The Taming of the Screw"
From Stuart Burgess:
If however this job [replacing gate-valves] is underway and you are
in the boatyard I would recommend the following
approach with new jobs.
More from Stuart Burgess:
Look at what has to be done. Read Nigel Calder's book on that job. 'Boat
Owners etc' Can the layout, setup, location be improved? Ask, Can you do it
yourself. If uncertain then get the guy from the yard to do the first
one / first job and stand 2 inches away and get him to chat. He will tell you
how to do it, the boatyard tricks that make the job easier ... and best of
all, he will probably be interested in doing the job on the side at night,
weekend etc, or he will know one of his mates who would like the job.
This is an art that took me a long time to learn. There are some jobs that
the yard can do in a fraction of the time because of tools and experience.
Most jobs however can be carried out by someone competent with knowledge.
You are obviously competent but won't have the knowledge YET. So pay the
minimum to get that part of the job done which will give you that knowledge.
Next time you will be able to do it yourself.
I have spent the last two days sitting in my bilge. Under the bilge is a
huge sump tank which is sealed in and takes all the grey water from the
showers and basins. When this reaches a certain level it activates a switch
which pumps it out through a fitting above the water line. It keeps the thru
hulls to a minimum and is a good idea. But to get to this sump is a
nightmare. The double bunk has to be stripped, the paneling removed, the
heat exchanger/calorifier wires removed and then the calorifier lifted out
with tubing attached ... and so it goes on, all to get to a stupid switch
that has some gunge on its sensors. Yesterday I changed it for an air
activated Par Hydro-air switch. No more bloody electrics in the gungy water.
The point is this ... a boat is made up of a large amount of complex
systems. It will take you a couple of years to understand the systems and
how they inter-relate. Yes, initially you will be overwhelmed especially as
what appears to be a simple problem defies solutions. You have to stand back
from it and be objective. You also must never lose sight of the fact that a
20ft boat is the same as a 44ft boat ... the only difference is scale. You
need to take your time on each job. Do not bodge a part of a system but look
at the whole system in relation to the boat. See what it's meant to do and
figure out if there is an easier/better more efficient way of doing it. Do
NOT be dismayed at the problems. The more problems there are the more you
will learn about your boat.
Most importantly, leave time to use and enjoy her. Go for a sail.
Anchor off and spend the summer using her. Fix things that break but don't
make any big changes until Winter approaches. By then you will have a much
better feel for her and the changes that you would like for your lifestyle.
This also avoids spending money on replacing one part when you may
want to change the whole system later on.
If your fuel tank or water tank etc has a leak. It doesn't mean that the
boat is crap ... it just means the tank needs replacing or repairing.
Last weekend my freshwater system was playing up. It wouldn't pressurise and
the system was full of air. Continually opening the taps to clear the air
would sometimes work and sometimes didn't. There were no leaks and the tank
was half full. The pump is working fine and drawing. This was a real head
scratcher and is not an uncommon problem. On Wednesday after several hours I
discovered the problem. It was a blocked air vent which allows the tank to
breathe. Simple, but not obvious.
Because your boat has 4 bilge pumps or 20 thru hulls doesn't mean that you
have to have them all working to be able to enjoy her. You only need one
bilge pump operating ... the rest can wait. Don't lose sight of this.
... just read your updated log. Boats are fun, aren't they.
Sounds to me that you are still very much overwhelmed.
This is a natural consequence of having high standards for yourself
and purchasing someone else's vessel where the standards have
been a little different.
You are not going to be able to do everything at once.
It is going to take you 24 months to sort her out.
If you have one crappy chainplate, then there will be others,
so don't rush to fix that one. There will be other jobs that require
the removal of headlinings etc in the future and that is the
time to fix these. You will also have made some contacts by then
which will help with materials and workmanship.
e.g. stainless steel costs very little when purchased from a steel stockholder.
You then find someone to shape it and learn to 'polish' it yourself.
Your thru hulls: Once you are out of the water you have to do what the yard will do.
Remember they will just replace the thru hulls so don't mess about with heating etc
to get them apart. Buy or hire a grinder and grind off one side or the other.
Hey presto a nice clean hole and no crappy thru hull.
Don't lose sight of the fact that these guys in the yard are no different than
you and I, they have just been doing it longer. They are not magicians and
many of them make dumb mistakes. When you use the yard, work on the principle
that you are hiring a teacher. Watch and learn and don't assume that what he
is doing is always the best way of doing that particular task.
Last weekend I noticed that the sealant joint between my pilothouse and deck
was pulling apart. On checking, it was being caused by the mizzen shrouds being
far too tight and as their chainplates are on the pilothouse roof they were
actually pulling the whole pilothouse skywards! This was rigging done by the
guys who rig the Oysters! So pity the poor Oyster owners.
Don't try and do too much all at once. Concentrate on one task and do it properly.
From RadarLove on Cruising World message board:
The most important attribute a "cruiser"/wanderer/voyager can have is a willingness
to tear into things that are broken and try to fix them. Handiness is not an inherited trait.
If you start taking apart things that are broken and try to fix them, you will learn to
use the tools, then you will find yourself buying tools and over time you will develop
the trait of "handiness". Trust me, this works. Just start.
From Leander on Interview With A Cruiser project:
Most marine vendors do not share your goal of having quality work done at a reasonable price.
Learn to do as much as possible on your boat, and be vigilant in those situations when you must pay for parts or services.
Time and again we've paid for work that was both overpriced and deficient, and typically found we have no recourse after the fact.
Who cares about you – you're sailing away to the next port!
With a little bit of practice, reading, and speaking to others, you will ALWAYS do a better job than someone
with less of a vested interest in the outcome. When others must be called in, define the scope of the work as
concretely and narrowly as possible, get things in writing, and watch the work like a hawk.
Kit Stansley's "Six Questions to Ask Yourself Before You DIY"
Message I sent to Warren Carter:
> My main Q is -- Can the coastal cruising life be done economically ?
> Is there a boat that can take years of sailing with low maintenance ?
> Or are boats just holes in the water, that we must throw money into ? : )
I'm no expert, but here's my guess:
1- All boats live in a hostile environment.
Some environments (e.g. fresh water, inland lakes) are less hostile than others.
2- You could reduce maintenance by not having equipment (KISS).
The extreme example of this: live on a raft or something.
3- You could reduce maintenance by letting your boat decay, as long as it
keeps floating, if that standard is acceptable to you.
4- You can reduce repairs by learning to use the boat properly and preventatively maintain it.
5- You can reduce the costs of maintenance by doing as much as possible yourself.
6- You can reduce the costs of maintenance by living in a labor-cheap area.
7- Some boats may be better constructed than others, and require less maintenance or repair.
I suspect that except for fundamentals such as hull blistering, deck leaks and delamination,
this is the least important factor.
From Steve Weinstein on The Live-Aboard List:
... You all know Boat Math, I assume. You start with a list of 10 projects, finish
8, and find yourself with only 15 projects left. Boat projects have a
definite kinship with rabbits. ...
From George and Sonia Kuperis in 11/2001 issue of Latitude 38 magazine:
... Don't take breakdowns personally or think that you are unique in
having problems. Yours is not a possessed vessel on which you have been
duped into spending your life savings. She's a machine with logical explanations
for her malfunctions. ... expect wear and tear that comes with a vessel in motion. ...
Frequently Asked Question:
How can I get a manual (or wiring diagram) for my boat ?
- If the manufacturer is still in business, contact them.
- Contact the owner's group, if one exists for that boat.
- Find other owners of that type of boat and see if they have anything.
- Otherwise, you're on your own. (Your boat may have been modified after
Trace systems and wires and examine components, writing down
as much as seems reasonable. For major components, contact their
manufacturers to get/buy manuals.
This section doesn't mention obvious stuff such as wire, nuts and bolts, etc.
Jim and Diane's "Spare Parts and Tools"
Chris Caswell's "Prepared for Anything"
SailNet - Liza Copeland's "Preparations for Going Offshore, Part Four"
Carry spares even if you don't know how to install them yourself.
Having them in hand can save expense and weeks of waiting when you have a breakdown
and find a mechanic in some remote place.
Inboard engine stuff:
- Fuel lift pump.
- Gaskets for head, heat exchanger, oil cooler, etc.
- Impellers for raw water pump.
- Raw water pump rebuild kit.
- Complete raw water pump.
- Complete fresh water pump with pulley wheel.
- Complete injector pump ?
- Engine thermostat.
- Complete engine starter motor ? Or maybe just the starter solenoid.
- Complete alternator (with pulley already mounted) ?
- Alternator rebuild kit (bearings, brushes, diodes).
- Starter motor rebuild kit (bearings, brushes).
- Engine starter motor solenoid.
- Injector lines.
- Injectors ?
- Exhaust elbow.
- Glass bowl for engine fuel/water separator.
- Engine sensors.
Outboard motor stuff (maybe genset too):
- Points and distributor kit.
- Ignition wires.
- Spark plugs.
- Carburetor rebuild kit.
- Intake reed/leaf valve ?
- Fuel filters.
- Impeller and gaskets (rebuild kit) for water pump.
- Fuel pump rebuild kit.
- Fuel hose and priming bulb.
- Propeller shear pin.
Navigation and controls stuff:
- Make and test a spare, jury-rigged rudder before cruising.
- Spare tiller, and test it before cruising.
- Steering cables.
- Throttle and transmission cables.
- Wind-vane panel/sail and break-away parts.
- Auto-pilot actuator/motor (the part most likely to fail).
- Auto-pilot belts and motor shear pins.
- Replacement valves, gaskets and valve plate assembly for refrigerator compressor.
- Spare (rebuilt) refrigerator compressor ?
- Refrigerator RFD (receiver/filter/drier) ?
- Jib hanks.
- Pieces of sail material.
- Webbing straps (Dacron or Nylon).
- Grommets and rings.
- Chafe patches (leather).
Rigging / deck hardware stuff:
- Winch parts (maintenance/rebuild kits) and special grease / machine oil.
- Swageless fittings.
- Bow roller.
- Lines of all sizes: label with length, thickness, material and intended use.
- Bolts for roller-furler and wind-vane.
- Extra blocks and shackles.
Raw stock for fabricating emergency parts (from Tom Neale):
- Aluminum and wood stock.
- Spray gasket (hot and cold types).
- JB Weld adhesive compound.
- Stainless steel rod stock (all-threaded and unthreaded types).
- Thin plywood and Life Caulk to repair holes in hull.
- Rubber inner-tube to cut up into gaskets, diaphraghms, insulators.
Moisture in air can degrade spare fuel and oil filters.
- Bilge pump.
- Belts, filters, wire, hoses, hose clips and clamps,
gaskets/seals/rings, anodes, fuses, lightbulbs.
(Best brand of belts: Gates.)
(Oil filters don't have to be "marine grade";
you will consume them faster than the environment can corrode them.)
- Propeller, castle nut and pin.
- Gaskets: roll of gasket paper,
roll of cork-type gasket paper, tube of gasket compound.
- Head rebuild kit.
- Water faucet rebuild kits.
- Pressure switches for pumps in pressure-water system.
- Marine-grade heat-shrink tubing (clear is best for electrical work)
with a glue/sealant that makes it watertight.
- Sockets for light bulbs.
- Circuit-breakers and fuses.
- Solenoid switches (for engine starter motor, head, anchor winch).
- UV-resistant thread for sails and canvas.
(Maybe from John Boyle ?
When using: "Spray the spool of thread with household
silicon spray - NOT oil! Don't just mist it, but really soak it.")
- Hydraulic hoses, tubing and fittings.
- Ventilation fans.
- SCUBA tank valve O-rings.
- Inflatable PFD re-arming kit.
- Oars and oarlocks for dinghy.
- Dry-cell batteries for flashlights, handhelds, etc.
- Eyeglass screws and screwdriver.
When you buy a rebuilt spare component, test it right away by using it.
This ensures that it fits and works, that you have the tools to install it,
and that the old part isn't frozen in place.
From Rick Kennerly on The Live-Aboard List:
... it's not the tool but how you use it.
(I think I got that from the Playboy Channel -- they do a lot of home
improvement stuff there).
"Basically, a tool is an object that enables you to take advantage of
the laws of physics and mechanics in such a way that you can seriously injure yourself."
-- Dave Barry
This section doesn't mention basic stuff such as screwdrivers, wrenches, etc.
Jim and Diane's "Spare Parts and Tools"
SailNet - Don Casey's "Putting the Right Tools On Board"
AC power tools are more powerful than DC power tools.
From my brother Dan (carpenter, electrician, etc):
First, a can of WD 40. Near salt water all of your tools will
go to pot unless you spray them down after use. Sockets, drill chucks, etc.
Hand tools: go to Sears. For hand tools, they have good quality
in the Craftsman line and will replace any that break, ever,
without a receipt. They are also reasonably priced and you
can heft them before purchase.
Disclaimer: This applies to hand tools only.
Do not buy power tools at Sears.
Here we have a dilemma. Normally, I buy good quality tools once.
My saws and drills have never been on the disabled list, but they
were expensive. The salt air may make this a bad option for you.
For a circular saw and a drill that are not too expensive
you might consider a Dewalt. I don't use them because I don't
think they are lifetime tools, but they should last you a while
in salt air. If you want the creme de la creme of drills,
buy a Milwaukee. They are double or triple the cost of a
Dewalt but they last.
Remember, with any tool it is the blade that counts.
When you buy your circular saw, buy two or three decent blades.
No saw is any good with a bad blade.
If you need an angle grinder, look at a Makita, or a Dewalt again.
I actually have two grinders, and the Dewalt has held up surprisingly well.
Spend Money On A Good Drill Index. You will use it a lot
and appreciate it. Don't get brad pointed drill bits, they are
great for wood but will not work in metal. You need a good
general purpose set.
Buy a good heavy GFCI extension cord. Undervoltage is the prime
cause of death in tools.
Other notes: On all tools, look for toolless blade changes
or at least a spindle lock, which holds the armature and allows
you to change blades with one tool.
I doubt you need a sawzall, but if you do, buy a Milwaukee
super sawzall and nothing else.
You should consider a jig saw. They are handy and with the
right blade can cut steel, wood, fiberglass, plexi, aluminum, etc.
If you buy one, get a Bosch. Once again, there is no better jig saw,
either to handle while working or for durability.
They run about $150.
Electrical: I have several meters.
The most versatile is a Fluke 11.
It is digital, does AC and DC, continuity, etc.
Auto ranging, rugged, shock and water proof.
From John Dunsmoor:
Another suggestion, this one is a little more esoteric:
go with air tools. If you are going to be on this game
and you have no investment in tools, air tools are great
and can't electrocute the user. A drop of oil once a day,
almost nothing to corrode, last forever, lower initial
cost (except for the compressor), can be used in and
under the water and will not electrocute the user.
This last point is pretty darn important when you are
attempting to buff the hull from the dinghy.
Buy from automotive tools/parts distributors/stores.
- Mask and fins (and maybe medium-weight wetsuit)
for emergency cutting of stuff wrapped around propeller or rudder,
for bottom inspection/scrubbing, and for anchor-set inspection.
- Kneepads; many jobs involve kneeling.
- Heavy-duty gloves.
- Compressed air for cleaning out air pump, air filter, carburetor, etc.
- Teluminator from Carica,
for picking up small parts dropped in bilge or under engine, or inspecting
things in tight places ? $120 or so.
- Magnet for picking up things dropped in bilge or over side,
and for testing parts to make sure they're stainless steel.
- Non-electric soldering iron.
Can double as heat gun, for loosening frozen nuts and hoses, removing varnish ?
Butane, with built-in igniter.
Such as Weller Portasol.
Really cheap small ones leak ?
- Welding/brazing/cutting torch: oxy-MAPP torch, or something from a welding shop ?
From Ken Hooper article:
... a tiny little oxy-MAPP torch that costs like $35 at Home Depot [or Sears],
although I went through an alarming number of $7 disposable oxygen
cartridges before the job was through. ... Although supplies for it
are expensive I do not regret buying it. This thing is capable of
field repairs if they don't require more than 10 minutes or so of
welding, especially if you pre-heat with a straight propane torch
before you start. A portable welder that's not much bigger than a
shoe box is, I think, a good thing to carry with you ...
A cheap real gas torch goes for $150 at your local welding supply
and uses the cheap returnable oxygen bottles. ...
- 12-volt Wet-Dry Vac. (Smaller better than bigger.)
- Non-contact infrared temperature-tester (for looking for hot bearings, etc).
Maybe at auto-parts stores or Radio Shack ?
- Dremel (with various wheels and attachments).
- Want toolbox made of industrial-grade plastic; no rust, and doesn't dent/scratch boat.
- Magnifying glass or loupe (8 to 10 power) for inspecting rigging fittings.
- Grease gun ?
- 12V test lamp and continuity tester.
- Multimeter (digital, with optional alligator clip on negative lead; recommended: Fluke 11).
Would be great to have "data hold" features, which preserve the reading after you remove the probes.
- Vise-grips (several sizes).
- Portable vise. (Maybe Wilton 4 1/2 inch Tradesman ? Maybe vacuum-mount electronics vise.)
- Telescoping, spring-loaded curtain rod (handy for holding things in position).
- Small anvil.
- Big pipe wrench.
- Good flashlight (critical safety item).
Tom Neale recommends Pelican brand.
Beth Leonard recommends halogen dive lights submersible to 100 feet.
LED flashlights reviewed in
Practical Sailor's 3/2000 issue.
LED flashlights: Photon Micro Lights,
Light Technology's PALight
- Funnel with filter screen and flexible neck.
Maybe one for fuel/oil and another for water ?
- Safety goggles.
- Hearing protection.
- Wire brushes for stripping paint.
- Tap and die set.
- Screw extractor set.
- Heli-Coil set (AKA "Thread Repair Set", "thread inserts").
- Pocketknife. Spyderco, Leatherman, Schrade are good.
- A close-quarter or right angle drill.
- Telescoping or dental mirror for seeing backs of things.
- A come-along.
- Manual (hand-powered) drill.
- Small sledgehammer.
Chris Caswell's "Engine Essentials"
- Penetrating oil.
PB Blaster, Kroil or others.
- Disposable rubber gloves (for working with epoxy, solvents,
fiberglass, diesel, cleaners).
- Respirators (for sanding, working with fiberglass).
- Wooden tongue depressors (for stirring paint, mixing and spreading epoxy).
- Caulks, sealants, solvents (acetone, MEK, muriatic acid, white vinegar, rubbing alcohol,
mineral spirits, "Brush Cleaner" from Home Depot, "Goof Off", "Goo Gone", etc),
cleaners, greases, paints.
- Electrical tape (buy good quality; maybe "self-vulcanizing rubber tape" ?).
- 3M waterproofing "gunk" for making watertight underground splices.
- White electrical tape for labeling wires.
- Plastic ties (black better than white) in various sizes.
Keep only wet/dry sandpaper on board; dry paper
absorbs moisture and disintegrates.
If clogged, wet/dry
sandpaper can be scrubbed with warm water and
detergent, then dried.
Sandpaper tested in 5/15/2001 issue of Practical Sailor.
Conclusion: premium paper (Carborundum Premier Red, Norton Blue A975, 3M Imperial Purple)
is well worth the higher price.
- Beeswax rings. From David Urbanski in
Good Old Boat newsletter:
... a wax ring, the 99-cent beeswax ring you put around the seal
of your land-based head. You can buy them at any hardware store,
and they last forever. The beeswax is an amazing thing; it can
stop water from entering or exiting just about anything.
It can be molded to fit any hole and used with any type of
surface, as long as you do not have a heat source close by
since the wax will melt.
The wax is also great in that once you have used it,
it's easy to clean away once the repair is made. ...
- "3M makes its own version of Velcro called Dual Lock that is
much heavier duty than normal Velcro."
- Click Bond patch kits
for repairing tank leaks.
- Marine-grade Never Seize.
- A couple of wire clothes hangers.
- Duct tape has water-soluble backing and messy adhesive; use "100 MPH Tape" instead (from www.uscav.com).
- Loos rig-tension gauge ? $100 or so.
- Nicopress kit (for rigging).
- Dye/oil for finding cracks in fittings
(e.g. Magnaflux, Ardrox, Spotcheck Red Dye).
- A "strand grip".
- Cable cutters (recommended: Felco's).
- Sewing palm.
- Needles (lots of strong ones).
- Hot knife.
- Seam ripper.
- Push pins (with wide heads, for pinning sail to wood surface).
- Pony clamps.
- V-92 sewing thread.
- Double-sided seaming/basting tape.
- "Rip-Stop" adhesive-backed sail fabric.
- Sail-repair tape: want Dacron, not Nylon.
- Sewing machine: see my Boat Sewing Machine page.
- Grommet/ring/fastener kits (including cutters and dies).
Basic refrigeration tools:
- Continuity tester.
- Thermometer to test temperature of refrigerator.
- Hair dryer to melt ice.
- Arsenic-free sealant rated for use in food compartments.
- Oven baster for forcing hot-water-and-baking-soda solution into drains.
- 12-volt power cable from light socket to alligator clips, with fuse.
- Dental mirror for seeing backs of things.
- Thin plastic tubing for clearing obstructions in pipes/drains.
Advanced refrigeration tools (for purging/recharging):
From "The Boatowners Mechanical and Electrical Manual" by Nigel Calder
(on Amazon - paid link
... [since 1994] only EPA-certified technicians can buy refrigerant. ...
Getting EPA Technician Certification
... Since 1993, the only people allowed to open a refrigeration system [coolant loop]
have been certified technicians. Any procedure beyond a simple topping-off
clearly constitutes "servicing" or "opening" an appliance and as such [must be
done by an EPA-certified technician]. ...
- Leak detector. (Electronic halogen detector $200 to $300)
- Vacuum pump. (e.g. Robinair 15234 for $425)
- Combination gauge set (2 pressure/vacuum gauges, 2 valves, 3 ports in one body).
(e.g. ATD-3201 for $60 includes hoses)
- Charging cylinder full of refrigerant.
(e.g. Robinair 43678B for $307, includes heater and gauge)
- Cans of refrigerant.
- Refrigeration oil ?
- Empty service drum or cylinder (for purging; put it in ice water).
- 3 hoses to connect everything together.
- Gloves for protecting from "finger burn".
Must have service valve (port) on low-side tube of refrigerator's compressor.
- Torque wrench.
- Coolant tester.
- PELA Oil Extractor
- Mail-in oil analysis kits.
Chris Caswell's "Oil Analysis"
"BoatU.S. sells kits in their catalog for $18.
All the major oil companies
and engine manufacturers have programs.
Pennzoil and Quaker State offer kits
through their distributors that cost $3 or $4 per sample."
Oil-changer guy at boat-show said a one-time oil-analysis is useless.
Only if you do a series of analyses over time and
see the trends over time do you get useful info.
"... oil to be tested should have at least 25 engine hours on it."
- Oil-filter wrench.
- Engine-belt tension gauge (Krikit or NAPA #KR1 for $10, or something fancier).
- Feeler gauges and spark-plug gapper, for outboard spark plugs.
- Engine compression gauge.
- Mechanic's stethoscope.
- Flush kit for running fresh water through outboard motor
cooling system: "rabbit ears" with hose fitting ?
- Impeller puller (allows you to pull and check an impeller without destroying it).
- Special tool for removing outboard motor flywheel.
- Battery hydrometer with built-in thermometer.
- Battery terminal pullers, wire brush and other battery tools.
- High-rate discharge battery tester.
NAPA battery load tester ($49)
- Jumper cables ?
- Distilled water.
Plastic welder ?
From Greg Hanka on the IRBS live-aboard mailing list:
I ordered my 2.8A (336W) Hejet plastic welder, plus the "high
speed tip" plus two pounds of rods of each of the six most common
plastics. That is probably a lifetime supply for a recreational
user like myself. It came a few days later as promised. I had
also ordered one for my brother, and it arrived at his house on
time as well. I used both welders and they behaved identically,
so Hejet quality control is at least satisfactory.
The gun itself is a glorified heat gun, apparently with very
precise temperature control. It is made of chromed steel and
plastic. Considering it won't be used that often, it would be
safe on a boat if kept in a dry container.
The instructions that come with the unit are pretty pathetic.
I expected at least a color booklet describing how to weld, or
even better a short video, but there were just a couple of xeroxed
pages giving a general overview of the process. You're basically
on your own to learn by experimentation. The instructions do say
that it takes about 30 minutes of practice to get the hang of it,
and they were exactly right. After a frustrating half an hour
with my brother's gun, I was able to weld one piece of rod to
another piece of rod (of the same kind of plastic of course) and
have the weld be stronger than the rod itself. That is the
indicator of success, says the instructions, and it is quite easy
once you learn the look and feel of the process. Both the Hejet
people and now I too strongly recommend buying the "high speed
tip", because it makes the process vastly faster and easier.
Anyway, after the practice session I went on full alert,
waiting for something made out of plastic to break so that I could
fix it. ;) The opportunity presented itself four days later. My
wife's HP Palmtop computer cover hinge finally gave out, after
going six months in a nearly-broken state. She immediately began
agitating for a new palmtop computer, since hers really wasn't
usable with the broken cover. Somewhat nervously, I attempted my
first 'real' weld on the palmtop. I guessed that it was made of
PVC plastic, which turned out to be right. (The welder comes with
decent tips on how to figure out what kind of plastic a thing is
made of.) Then I fired up the gun and just did it, and was fairly
surprised that I got it right on the first try, without melting
the surrounding case plastic much at all. The hinge works perfectly
now, and I was unable to pry off a piece of welded plastic from the
case with a razor, so the bond was good. Indeed, this is the first
time that a gimmicky tool has actually, truly paid for itself on
the very first usage.
Wifey was impressed, as you might imagine. The idea of
actually repairing a broken plastic item is surprising to most
people. The only difference between my weld and that done by a
pro, I think, is the aesthetics ... mine is perfectly strong but
not real smooth, even after a bit of filing. It's still fine though.
So plastic welding is for real, and the Hejet tool works as
advertised. I don't have any experience to know if other types of
plastic welders (e.g., soldering-gun type) work better, but I
don't think they do: hot air seems to be the simplest way to
uniformly heat a controlled area of two separate pieces of plastic.
Of course, hot air welders are four times the price of soldering-
gun welders. :(
Eventually, I'm going to build some polyethylene holding tanks
and buoyancy tanks in the odd shapes needed on board my boat, now
that I'm certain that I can make genuinely strong welds in plastic.
In fact polyethylene seems to be one of the easiest plastics to weld.
From Stuart Burgess:
One of the most useful tools I have on my
boat is a vacuum pump. I bought it from a specialist car accessory shop but
they are advertised in the West Marine catelogue as an 'oil boy' fluid
I use it for removing water from difficult places. I discarded the 2nd
extension pipe and replaced it with a length of copper tubing in which I
placed a gas tap as an on/off switch. I covered the copper tube with a piece
of plastic hose so not to damage any joinery and now to suck water out of
tricky places I simply place the end in the water, pump the container to
depressurise it and then open the on/off tap to begin extraction.
It has saved me many hours of work.
SCUBA equipment: see my SCUBA Diving page.
- Bilge pads or booms (constructed of special fibers that absorb hydrocarbon
fluids but repel water).
Bilge pads tested in July 2001 issue
of Boat/U.S. Magazine.
- AC outlet polarity tester.
- Fingernail polish bottle with integral brush
(fill it with varnish and use it for quick varnish repairs).
- Special tool (corkscrew on flexible shaft) for removing stuffing-box packing.
- Metric pigtail, to fill propane tanks outside USA.
- Super Siphon
for transferring fuel between tanks and cans.
SailNet - Tom Wood's "The Lowly Boat Pole"
Review of boat-hook devices for snagging moorings and pilings,
in 10/1/2000 issue of Practical Sailor.
Make one from shovel/rake handle or oak curtain rod, and cast bronze boat hook casting.
Plastic is best (doesn't corrode, doesn't scratch gelcoat).
Put an oil-absorbent pad in the bottom of each toolbox.
Put small tools and parts in clear plastic boxes, with silica gel packs.
- Store tack rags and solvent-soaked rags in airtight containers
to avoid drying, leaking or spontaneous combustion.
Harbor Freight Tools
A wench is used to turn a dolt's head.
Troubleshooting / Techniques
"The man who would be fully employed should procure a ship or a woman, for
no two things produce more trouble"
- Plautus 254-184 B.C.
Cruising World's "Find It, Fix It, Maintain It"
Dolphin Marine's "Technical / Troubleshooting Information"
Don Stewart's "Rust Ye Merry"
David Pascoe's "Attaching Hardware to Your Boat"
SailNet - Sue and Larry's "Drilling and Filling Holes in Your Boat"
Don Casey's "Installing Hatches and Deck Plates"
SailNet - Tom Wood's "Mounting Deck Hardware"
"How to Drill Holes" by Wayne Redditt in issue 2000 #2 of DIY Boat Owner magazine
David Brown's "Repairing Loose Bulkheads"
Chris Caswell's "Quick Engine Repair"
SailNet - John Kretschmer's "Tips for Going Overboard"
- Must-have books:
- "The Boatowners Mechanical and Electrical Manual" by Nigel Calder
(on Amazon - paid link).
Contains theory, installation, troubleshooting, repair info for many things.
- "This Old Boat" by Don Casey
(on Amazon - paid link).
Walks through simple and complex projects in many technologies.
- Very-good-to-have books:
- "Modern Boat Maintenance" edited by Bo Streiffert
(on Amazon - paid link).
Tips and projects for hull, deck, rigging, sails, engine, electric.
- "Marine Diesel Engines" by Nigel Calder
(on Amazon - paid link).
First half is theory and design, but second half is troubleshooting,
- Good-to-have books:
- "Complete Guide to Boat Maintenance and Repair" by David G. Brown
(on Amazon - paid link).
General techniques (drilling, gluing, fiberglass, bedding deck hardware, etc)
and then specific tasks (fixing blisters, fixing leaks, improving ventilation,
maintaining winch, etc).
- "The Compleat Book of Yacht Care" by Michael Verney
(on Amazon - paid link).
A lot on painting, and splicing.
Pretty good on engines, mechanics, fittings, dinghies.
Slightly dated (1986) and slightly British/wood-oriented.
- Worth reading:
- "The Self-Sufficient Sailor" by Pardey and Pardey
(on Amazon - paid link).
- "Your Boat Belowdecks" by Thomas Reale and Michael Johnson
(Your Boat Belowdecks.).
Maintenance and troubleshooting of engine, electrical, pumps, head, etc.
- "Improve Your Own Boat" by Ian Nicolson
(on Amazon - paid link).
Odd mix of small and large projects, tips and anecdotes.
- "The Boat Repair Manual" by George Buchanan
(on Amazon - paid link).
Covers a lot of territory, including various hull types,
all parts of boat, equipment, maintenance.
Slightly dated (1985) and somewhat British/wood-oriented.
Cap'n Drew, quoted in 9/2002 issue of BoatU.S.
> I was given a 1972 trawler which has not been in
> the water for over 10 years, and needs a considerable
> amount of work on hull, cabin and engines.
> What book should I get to help me ?
You might want to consider the Bible.
I think you're gonna need a lot of prayers to get you
through this one. ...
Don't put off repairs to critical systems: engine, dinghy,
pressure water system, batteries, ground tackle.
If the weather changes and you have to move
or have to stay a while, those systems must be up.
Rebedding Deck Hardware
Mostly from "The Voyager's Handbook" by Beth Leonard
(on Amazon - paid link
- Remove the hardware.
- Sand and clean the deck with solvent.
- Drill out holes, clean out dirt.
- Remove coring around holes.
- Fill holes with epoxy, drain it out, then fill with thickened epoxy, let it harden.
- Drill and tap bolt holes.
- Dry-fit the hardware, tape on and around the hardware, then remove the hardware.
- Put lots of sealant on hardware and bolt heads and deck (but not on backing plate).
- Tighten slightly, let dry, trim, tighten a little more.
From Jay Fraser on the Yacht-L mailing list
... The stanchion job is perfect for practice: you are replacing rotten balsa
wood, so ANYTHING you do will improve the situation.
0) Clean everything w/ acetone. Wear breathing mask.
1) Put tape over bottom hole.
2) Fill with un-thickened epoxy (this wets out the surfaces inside hole).
3) Pull tape, catch epoxy that leaks out, clean up spills.
4) Put new tape over bottom hole, thicken epoxy.
5) Force as much epoxy into hole as possible, w/o popping tape off bottom.
6) Repeat as necessary.
7) Go drink ONE beer. You won't need any more after all the acetone fumes
you've been inhaling.
From Norm on The Live-Aboard List:
Make up the joint using spacers to insure an
adequate layer of sealant between the base and the deck. I use 1/8" diameter
pieces of wire.
I first make up the joint dry with the fasteners to make sure everything fits
well. Draw a pencil line around the joint. Take it apart and put blue
masking tape on the deck at the pencil line, and around the edge of the object to
be bedded. It is much easier to apply the masking tape than it is to clean up
the excess without masking tape.
Then tape down the pieces of wire to the deck with just a little of the wire
over the line so that it is between the deck and the object. Then put down a
generous bead of bedding and make up the joint. The wires insure that there
will be exactly 1/8" of bedding between the object and the deck. The next day
remove the tape and wires and clean up. Do not put any load on the joint that
will squeeze the bedding out. You might try methods that will remove the
tape and excess bedding but leave the wires in place. Wait until the bedding is
cured to a quite firm state and then tighten up on the fasteners.
The object is to make a perfect formed-in-place gasket 1/8" thick and then
put it under compression.
The wrong thing is to squish all or most of the bedding out. This will leave
a very thin gasket so that the slightest movement of the object will break
the adhesive seal of the bedding material and allow water to wick in.
From "Good Boatkeeping" by Zora and David Aiken
(on Amazon - paid link):
- Use "Rubba Weld" tape for emergency repair to water hose.
- Put little tape marks on all engine gauges to show typical reading;
any change may mean a problem.
- If electronics get wet with salt water, rinse them with fresh water.
Paraphrased from "This Old Boat" by Don Casey
(on Amazon - paid link):
Basic skills to acquire and practice:
- Fiberglass work.
Sealants / caulks:
Mostly summarized from article in March/April 2000 issue of
Good Old Boat magazine
- Chemically impervious (fuel and oil resistant).
- Compatible with plastics.
- Good for separating dissimilar metals.
- Cures rapidly.
- Weak bonding, especially to wood.
- Can't be sanded or painted.
- Needs UV-inhibitors and mildewcide mixed in; only use marine-grade.
- Polysulfide (e.g. Boat Life's Life Calk, 3M 101):
- Can melt some plastics, acrylics, Lexan, vinyl.
- Bad for separating dissimilar metals.
- Less elastic than silicone.
- Cures slowly.
- Can be sanded or painted.
- Can last 20 years.
- PolyGone removes polysulfide caulk.
- Polyurethane (e.g. 3M 5200, SikaFlex 292):
- Extreme adhesion; near-permanent bond (3M 4200 less permanent).
- Cures very slowly.
- Diesel fuel softens/damages 5200.
- After you open and then close a tube of 5200, the whole tube solidifies
in a few days to a couple of months (depending on who you ask).
- 5200 can't be sanded.
- To remove polyurethane/5200: Anti-Bond 2015, or turpentine (soft
while wet with turpentine; when dries, it's hard again), or Lestoil floor cleaner.
- Flexible Epoxy (e.g. Flexbond Marine Epoxy):
- Near-permanent bond.
- Cures underwater.
Summarized from "Complete Guide to Boat Maintenance and Repair" by David G. Brown
(on Amazon - paid link
- Silicone: shorter lifespan, can peel loose, damages some plastics.
- Polysulfide: best for ports, deck hardware, everything.
- Polyurethane: too permanent for most jobs.
From SailNet - Don Casey's "Choosing and Using Sealants"
... think of silicone as a gasket material instead of a sealant
... because it depends upon mechanical compression to maintain
its seal, silicone is also a poor choice for sealing hardware
on a cored deck ...
... You can - and should - use polysulfide to bed almost everything.
... One caution: do not use polysulfide to bed plastic.
... Consider polyurethane an adhesive [that forms a
permanent bond] rather than a sealant.
BoatLife's Life Seal:
part silicone and part polyurethane. ...
this mixture promises a longer-lasting seal
for deadlights and other plastic fittings where compression
of the sealant cannot be assured. ...
Solvents for cleaning up:
- For silicone, use acetone.
- For polysulfide, use mineral spirits.
- For polyurethane, use rubbing alcohol.
Summarized from John Dunsmoor:
Use 3M 5200 when bonding to metal; the bond can
be broken later by heating the metal.
Don't use 3M 5200 when bonding two pieces of
fiberglass/plastic together; the only way to get
the bond apart later is to saw down it.
From Bill Millson on the Morgan mailing list:
... 5200 and 4200 do not weather well in the sun -- mine started chalking and
giving off black marks within a few months ...
From LB on the Morgan mailing list:
... let the 4200 cure well then sand lightly and paint. I
have done this before and it works out well. The 4200 or
5200 is fine after years. It is only the UV that gets to it.
West Marine's "Sealant Selection Chart"
To smooth wet caulk without sticking to it, dip tools
or your fingers in detergent such as Joy.
Any time you're rebedding deck hardware, consider taking the opportunity
to add bigger backing plates to it.
For sealing deck leaks: Elmer's Squeez-N-Caulk (siliconized acrylic latex) ?
Don't use acetic-acid-cure silicone (with vinegar smell) on copper or aluminum.
From my brother Dan:
[When I complained about a cap that split and let all of my caulk dry in the tube:]
Buy a 99 cent toilet bowl wax seal, the very cheapest possible, and dip
your caulk tubes into it when you finish a job. The wax will seal the
end better than any cap can, and you can just squish it out later.
From Gary Elder:
[After he told me not to use silicone to bed metal hardware
or teak strips onto fiberglass deck:]
> Okay, so when should I ever use silicone ?
Silicone is good for metal, glass, lexan, abs plastics, etc.
> Is polysulfide harder to get off later ?
Not really, polysulfide may seem harder to remove, but silicone leaves a
residue behind that can cause polysulfides to not stick real well.
I haven't purchased silicone sealant for this boat - ever.
From Marce Schulz on The Live-Aboard List:
> When we used BoatLife polysulphide, we had to re-do the entire deck
> because the stuff had cracked inside.
Wow! Same thing happened to us! We got BoatLife to replace the stuff that
didn't work (although they didn't admit liability of course, and the labor
involved was tremendous) but in the end we decided not to chance a complete
product failure again and went with Teak Decking Systems SIS 440, after
testing about 5 different products on the fantail and waiting a year to see
what held up best. In fact, we just finished the job 2 weeks ago. We may
even consider using the same stuff to bed the deck hardware. It's a joy to
From Bob Hinely on The Live-Aboard List:
Lifeseal is a mixture of polyurethane and silicone. It is an excellent
sealant for Lexan-Fiberglass ports.
From Ken on Cruising World
There is a known chemical incompatibility
between CETOL and Boat Life 2-part polysulfide caulk. The CETOL
when applied over the caulk eventually breaks it down. You end
up with a sticky mess, the caulk "bubbling" out of the seams
like tar on an old ship. Heat (hot days) seems to accelerate the problem.
From Cam Foster on SailNet's Gulfstar mailing list:
... After struggling a number of times through the process of
removing the old caulking, I found a "magic" product made by Boatlife called
Release -- an adhesive and sealant remover. Costs about $16 for a 16-ounce
spray bottle. Spray it on the old caulking (even at the top of the windows),
wait a couple of minutes and you can almost pull the old stuff out in a
string, with some help of a skinny putty knife. It even works on relatively
new caulking ... If you spray it on and then change your mind, let it dry
and it re-seals. ...
From Sailingdog on SailNet forums
Marine Sealants in a Nutshell
One thing you have to do on boats is bed hardware. This has to be done on a regular basis,
especially with hardware that is under heavy cycling loads, like cleats. However,
using the right sealant can make this task much simpler.
Most people are familiar with silicone caulk, since it is the most commonly
used type of caulk in normal household repairs. However, while certain
Silicone-based bedding compounds are excellent for bedding ports, most of the time,
silicone caulks really serves no useful purpose on a boat beyond bedding ports
and covering the ends of cotter pins.
In most cases, on a boat, you want a sealant that will adhere to the two surfaces
being joined — whether it is a through-hull and the hull or a cleat and the foredeck.
The sealant should have a fair bit of elasticity so that it can stretch when the
hardware moves or shifts under load without detaching from either side and breaking the seal.
For deck hardware and through-hulls, countersinking the fastener holes is probably
one of the best things you can do, since it gives the sealant a natural place to form an o-ring-like seal.
There are four major classes of bedding compounds/sealants used on a boat:
- Polyurethane-based sealants such as 3M 4200 and 5200, SikaFlex 291, 292, 295, 296.
- Polysulfide-based sealants such as LifeCaulk and 3M 101.
- Silicone-based sealants, such as Dow 295.
- Butyl Rubber Glazing tape — this is not butyl rubber caulk.
Each of these sealants has specific pros and cons.
Polyurethane-based sealants are basically adhesives with sealant properties.
They are often very permanent and have very strong adhesion strength, and can
be used both above and below the waterline.
3M 5200, a polyurethane sealant commonly found in marine chandleries,
is basically for all intents and purposes a permanent adhesive and should
not be used on boats for the most part. 3M 5200 has a bonding strength so
high that it can often cause delamination or damage the gelcoat when you
try to remove hardware bedded with it.
However, polyurethane sealants have some of the best materials compatibility,
so the less aggressive ones, like 3M 4200, are very useful. SikaFlex 291 and 292
are probably better choices, but usually more difficult to find. For bedding ports,
Sika 295 or 296 can be used in place of Dow's 795 Silicone.
Be aware that using a polyurethane sealant can make removing hardware much more
difficult than using other sealants. There is a solvent, called DeBond 2000,
which can be used to weaken the bond if you need to remove hardware that was
bedded with 5200. One other issue with the polyurethane sealants is that they
have a relatively short shelf-life, once opened. This is due to their being moisture-curing
compounds, and once exposed to the moist sea air ... they start to cure ...
and you eventually end up with a solid tube of cured sealant.
Polysulfide-based sealants are the best general-purpose sealants for marine use.
They are not as aggressively adhesive as polyurethane-based sealants and generally a
bit more elastic and flexible. They can be used both above and below the waterline,
like the polyurethane sealants, and are better than polyurethane-based sealants for
hardware that has to be re-bedded more frequently.
Polysulfide-based sealants are excellent for bedding wooden items, like rubrails
and cockpit coamings, since it adheres fairly well to teak. The fact that these items
often need to be removed for periodic re-finishing makes it ideal IMHO.
The main drawback of polysulfide-based sealants is that they tend to attack many
common plastics — most commonly acrylic and polycarbonate. They are safe to use on acetal,
delrin, nylon, and marelon fittings though. If you're not sure what the fitting is made of,
don't use polysulfide-based sealants with plastic fittings.
Silicone-based sealants aren't really sealants IMHO. They're really gasket materials, and
need to have a minimum thickness and be kept under compression to work properly.
Silicone-based sealants should only be used in above-the-waterline applications.
The only structural silicone sealant that I generally recommend is Dow 795. This is a
structural adhesive which is generally recommended for bedding ports. It is not your
common silicone caulk. However, beyond the very specific use of bedding acrylic* ports,
it should not be used on boats.
Aside from bedding acrylic and polycarbonate ports, and certain plastic parts,
like Beckson ports, and covering the exposed ends of cotter pins — it really has no
place on a boat — primarily due to the residual silicone contaminants silicone
can leave behind. These contaminants are almost impossible to remove thoroughly,
and will prevent other sealants and paints from adhering to the surface properly.
Even strong adhesives, like epoxies, have trouble bonding if the surface has silicone contaminants on it.
One other use of silicone is for sealing potable water tanks. However, I highly recommend
that you use only NSF approved silicone sealants for potable water tanks and systems.
These will not have any toxic components, unlike some of the other marine-grade sealants
which may contain isocyanates.
Some silicone sealants are acid-curing and should never be used on metal. These are
generally easily detectable by the strong vinegar smell caused by the acetic acid
that is contained in them.
The last sealant is butyl rubber glazing tape. This may be one of the most versatile
sealants you can use on a boat. However, it has the weakest adhesion and tensile
strength and highest elasticity of any of the sealants. It is also the most easily
affected by other chemicals, as it doesn't cure like the other sealants do.
Unfortunately, many petrochemicals and common solvents will dissolve or damage it.
Because of its sensitivity to petrochemicals, I generally don't recommend it be used below the waterline.
It is great for bedding deck hardware, especially things like chainplates, where a
certain degree of movement is unavoidable. It has the greatest materials compatibility
of all the sealants and is also probably the least expensive of them.
One major advantage of butyl tape, since it doesn't cure, is the working life.
This makes it ideal for bedding things like traveler and genoa fairlead tracks.
The lower physical strength of butyl tape generally isn't an issue due to the
large number of fasteners generally used on these tracks.
Two other sealants of note for marine use are 3M 4000 UV and BoatLife's LifeSeal.
3M 4000 UV is a polyether based sealant, and as such is generally fairly well
suited for use with plastics. However, it is not recommended for below-the-waterline uses.
It cures relatively quickly, as it is tack-free in under half-an-hour and cures in 24 hours or so.
BoatLife's LifeSeal is a hybrid polyurethane/silicone sealant. As such, it isn't as
permanent as a pure polyurethane sealant, but is more an adhesive bedding compound
than a pure silicone material. However, it still has many of the contamination issues
that any silicone based sealant will have. It also is fairly inelastic, and IMHO,
3M 4000 UV is a better choice.
*Most marine ports should be made of cast acrylic, rather than polycarbonate, due
to several physical characteristics that make polycarbonate less suitable. First,
polycarbonate tends to deform under load, which can cause it to shear the adhesion
of the glazing to the underlying sealant. Second, it is less scratch and UV resistant
than acrylic. Third, it is more difficult to find polycarbonate in UV/scratch resistant
versions in sizes thicker than 1/4".
I used to use 3M 101 (polysulfide) caulk on everything except plastic ports (used
BoatLife Life Seal on those).
But the price of 3M 101 kept rising and it got harder to find. So I've switched to
using generic acrylic latex "tub and tile" caulk. It's paintable and interior/exterior
and "provides a water-resistant seal",
and costs about 1/5 as much as 3M 101. Will have to see how well it works and lasts.
I've never used 5200 or 4200 adhesives on my boat.
I've used silicone caulk on the pilothouse trim and pilothouse windows, but
From Ocean Navigator: Roger Hellyar-Brooks "General Fabrication":
... In review of all the goops and glues we could use to connect things to the
boat, some are better suited than others, but there are many methods
that can work, as well. When fastening a composite or plywood structure
to a boat (fiberglass or cold-molded wood), it is hard to beat the
versatility and strength of an epoxy bond. Some vinylester resins have
good secondary bonding characteristics (anything after the boat is
molded), but avoid polyester resins, since they are good for boat
construction but do not make the best adhesive.
The prep work for all bonding must be done carefully, because, as with
painting, preparation is the key to a successful job. First scrub the
area on the hull or deck with anything that gets kitchen floors clean
and dewaxed. You'll know you are successful when the rinse water
"sheets out," which is the opposite of water beading on a well-waxed
surface. Do this before you even think about grinding or sanding, since
that will cause you to drive contaminants into the surface. After
washing and rinsing, wipe the surface with alcohol or acetone
(ventilate well) and abrade the surface to provide a mechanical
Surface preparation (summarized from article by Brian Knight in Epoxyworks #20 Fall 2002):
- Don't wipe a surface with an organic solvent unless there is good evidence that
an organic contaminant is present.
- Organic solvents can dissolve contaminants from rags (silicone from
fabric softener, plastic from man-made fibers) and deposit them
on the surface.
- Use white or unbleached paper towels, not rags. Use them
to wipe solvent on, and then more to dry the surface.
You want to wipe the solvent off while it is still wet.
- Don't rub your bare hand over a freshly sanded surface;
that deposits skin oils and salt onto it.
- To get sanding dust off: vacuum it, brush it, or wash off with clean water.
Compressed air can have oil in it.
- Commercial "tack rags" may deposit a residue. Solvent in paint
or varnish may handle the residue, but epoxy won't.
- Don't use sandpaper that has been treated with zinc stearate;
that can contaminate the surface.
- Amine blush (wax-like film) on cured epoxy is water-soluble.
- To test for clean surface, wash it with clean water and look for
beading or channeling caused by contaminants.
- For good adhesion, surface should be clean, dry, solid,
and either porous or abraded (sanded).
Underwater repair compounds:
Summarized from article in 12/2001 issue of Practical Sailor
Not many products specifically targeted at this use.
Some hull types (wood, aluminum) very hard to bond to.
No products were entirely satisfactory: some too slow-curing, some too weak.
Bio-Fix 911 cures quickly but only moderate holding. Use duct tape or
wedges to hold a plate on, and Bio-Fix 911 to seal joint.
Epoxy sticks (AquaMend, QuikAluminum) good for filling small holes.
Replace stores of products every year or two.
From letter by John Vigor in 1/15/2002 issue of Practical Sailor
Use a mixture of tallow and fast-setting Portland cement.
Doesn't set until put underwater.
Get a watertight can of the cement.
Remove frozen/corroded nuts/bolts/fittings:
Chris Caswell's "Fastener Removal"
Remove a frozen nut
Remove a frozen or sheared bolt/screw
Partly from "Sailing Tips" by William M Burr Jr
(on Amazon - paid link
partly from article by Ken Textor in 6/1998 issue of Cruising World magazine
- Clean nut before trying to loosen it; rust/dirt increases chances of rounding it off.
- Use box-end wrench, not open-end or adjustable wrench, or pliers.
- Try tightening nut slightly.
- Tap the nut gently with a hammer.
- Use penetrating oil (or Diet Coke, which has phosphoric acid in it)
(or Coca Cola and baking soda).
- Use vinegar on rusty nut (dissolves aluminum oxide over time).
- Use nutcracker to split the nut.
- Heat the nut.
- Drill diagonal hole in nut to expose threads to penetrating oil.
- Drill small holes in nut (don't hit threads) until it can be chiseled apart.
- Weld a bigger, square nut to the stuck nut.
If head is still on:
- Clean head before trying to loosen it; rust/dirt increases chances
of destroying slot or rounding off hex head.
- Use the best tool first (the proper size screwdriver, or a box-end wrench).
If you damage the head with the wrong tool before trying the best tool,
the best tool may fail too.
- If a bolt doesn't move easily, use penetrating oil immediately,
before applying excess force and maybe breaking something.
- Try tightening it slightly before trying to loosen.
- Tap gently with a hammer onto the screwdriver, to shock the bolt, and to seat
the screwdriver well into the slot.
- Substitutes for penetrating oil: Diet Coke (has phosphoric acid in it);
Coca Cola and baking soda; vinegar (dissolves aluminum oxide over time).
- Heat the nut or the bolt/screw.
- Use an impact wrench.
If head is snapped off:
- Use file or Dremel to cut a new screwdriver-notch in top of the remaining shaft.
- Hammer a wrench onto the shaft, then turn the wrench.
- Drill hole in top of the remaining shaft, then insert screw remover/extractor
(left-handed screw; AKA "easy-out").
Start with very small drill bit.
Use a high-quality carbide or cobalt or titanium-coated drill bit.
If top of shaft is flush and flat,
use a center punch to make a dimple in the center of the shaft before drilling.
If top is not flat, use a file or Dremel to make it flat before punching.
If top of shaft is below surface, hammer a hardwood dowel into the hole and
cut it off flush; the dowel will help support and guide the drill bit.
- Drill entire screw out. Far better to use a drill-press rather
than a hand power-drill.
- Use a "hammer drill" (or "drill hammer" ?).
- Weld a big, square nut to the head of the stuck bolt/screw.
From yachtgilana on The Marine Doctor's Forum:
Extraction of broken bolts and studs:
OK, here is the broken stud 101, that I use, and have used successfully many many times.
Credit goes to Graham my Audi technician from Cape Town who taught me this.
The smallest bolt I have extracted is 6 mm and the biggest 22 mm.
It's not cheap but it works.
- Get a flat-ended pin punch, and beat the end of the stud square and flat,
use many light taps, like hundreds!
- Get a centrepunch, and even if you have to grind it especially, punch a dot in the centre.
- Start drilling with very small bit, watch your feeds and speeds, make sure
there is swarf coming out the hole otherwise the metal you are working is
work-hardening (then give up) this is especially true on stainless.
- Keep a cool tool! Lube the cutting edge, go get out there and buy the
cutting oil in a spray-can, it's worth it!
- Now go out and buy a torx or spline drive socket or driver.
For those who don't know what it is, it's either a socket that fits on your
socket set that has a very hard tip consisting of six sharp points in the
case of torx, or 12 in the case of a spline, or a screwdriver type.
They are numbered, like Torx #6 etc. Buy one that is smaller than the ID
or root diameter of the thread in practice 1/3 the OD (leaving a third of
"meat" either side of the hole otherwise it will shear off again).
- Examine the torx from the end, see that there is an inner and outer
diameter ... (the valleys and peaks of the points) your final hole is
the same size as the INNER diameter, like it won't fit right ... right!
- Take the torx to your bench grinder, and grind the tip, without
overheating it, so that it is 90 degrees and has SHARP points not the
nice shamfered end as new which aids getting it into the torx head screw.
- Hammer the thing into the hole you have meticulously prepared,
the points should cut their way into the metal of the screw
AND NOT EXPAND IT so that it is even tighter!
- Attach your handle and unscrew the little bastard!
Stainless steel fitting corroded onto aluminum mast:
Connect battery ground to aluminum, briefly touch battery positive to stainless steel.
Heating at boundary will help free it.
Bronze frozen onto bronze: use Tabasco sauce.
From Ike Harter in Good Old Boat
Get some glazier's putty, children's modeling clay or electrician's
caulking compound and build a small dam around the nut or cap screw
that is frozen in time. The stuff needs to be oil-based, not water
soluble, such as Play-Doh or other washable goo. Degrease the area,
and remove any penetrating oil you might have tried before.
The little dam needs to be molded so that it will keep the nut,
screw head, stud end, or whatever is stuck, submerged in at least
two ounces of liquid. Now fill the reservoir with regular Pepsi-Cola.
Coke and some of the other colas and soft drinks may work, but Pepsi
has more phosphoric acid, which is what does the job, along with
the carbonic acid and something in the formula that makes the
liquid penetrate into the threads and cracks.
Check each application for leaks and leave it alone for about six hours.
If you have several stickers, make as many dams as you need.
Check in an hour or so for leaks, but leave it alone and let it work.
Don't loosen the dam just yet, unless you cannot get the wrench on the nut.
In most cases the fastener will unscrew as if by magic.
If it is still frozen, try another application of fresh Pepsi.
Six hours later if it still will not move, then you need a
nutcracker or cold chisel. Your problem is beyond the capabilities
of channel locks and Vise-Grips.
Another possibility, which has caused many salty words from
mechanics and sailors alike, is that there may be a hidden problem
that even Pepsi cannot dissolve. If you don't know the history of
the machinery or the fastener, consider this. Some well-meaning
soul may have applied a LocTite compound to the joint.
It might as well be welded.
LocTite is a family of anaerobic, cyanoacrylate resins which
have unusually good penetrating qualities and which harden
when out of the presence of air. If you think this may be the case,
done either at manufacture or during a repair, get an
ultra-violet "black-lite" source and in a
darkened space, illuminate the subject in "black-lite".
Any traces of LocTite will fluoresce in a color that
will indicate the grade of LocTite that was used.
Get out your propane torch or a really big soldering iron.
The joint or fastener will need to be heated to about 350
degrees F before it will break down the resin.
The fastener will need to be unscrewed while hot.
Never apply anaerobic thread and bearing sealant compounds
without first considering whether you or some poor unsuspecting
person will come after you and end up losing their temper,
manners, and religion over a very tight joint.
On the matter of penetrating oil, most of the naphtha-based
graphite suspension products have been withdrawn because of
the carcinogenic qualities of the liquid. An alternative is
Oil of Wintergreen, sold at the pharmacy, but try Pepsi first.
Buy it by the case for flushing out fresh and seawater corrosion
in motor blocks, pumps, and circulating systems. Good stuff.
From Norm on The Live-Aboard List:
Aluminum has twice the expansion of steel. To get the wheel off a shaft, I would
apply a gear puller, with lashings or spiral clamps for security, put as much
tension on it as you dare, then apply significant heat to the hub of the
wheel. Personally, I find that lots of heat applied quickly, before it has
time to spread, works best. ... invite all your friends and ask them to each bring a
propane torch. Apply all the torches at once. When the heat is as high as
you dare and the thing still does not pop off, whack the end of the screw on
the gear puller with the biggest hammer you can find. If that doesn't do it
then cut the hub in half with a hacksaw and weld it back later.
Aside about hammers. When you want to move something, use one great whack with
a big hammer. Medium whacks with a medium hammer only move metal around.
If any particular whack does not move the parts, many of the same force will
not do it, and often will make the situation worse by peening metal around.
If you use WD-40 and then try penetrating oil,
the WD-40 residue will prevent the penetrating oil from working.
Use penetrating oil first.
Keeping bolts and nuts tight,
summarized from "The Voyager's Handbook" by Beth Leonard
(on Amazon - paid link):
Don't use Loctite when plastic is present (even a nylon locking sleeve inside
a nut); it attacks some plastics.
- Lock washer.
- Aircraft locking nut.
- Drilling and wiring/cotterpin.
- LocTite or a dab of silicone caulk.
Tapping a hole, from Larry Helber on Yacht-L mailing list:
... Don't forget to get the T-handle for the tap. It is worth it and makes the
job of tapping a straight hole much easier.
Tapping a new hole is very simple. Just drill the hole and make sure it is
perpendicular. Put the tap in the T-handle and screw it in.
[Maybe use some lubricant too.] Every one or
two turns back the tap out 1/4 turn. This will break off any burrs that would
jam the tap. Keep doing this until the tap is all the way in. Unscrew the
tap and you are ready for the next one.
From Eric Thompson on The Live-Aboard List:
When using either a tap or a die, the correct procedure is to turn the tool 1/2 turn,
then back to 'break out' the cut metal. Then you proceed to the next 1/2 turn.
From Gene Gruender on The Live-Aboard List:
After cutting the threads, run the tap or die the length of the work area again to insure clean threads.
When using a tap it is important to have a hole that goes THROUGH the piece of metal, or you must
buy a tap specifically designed for use in a 'blind' hole. It will have a much shorter tapered
section (and be harder to turn).
Try to keep the tool as perfectly perpendicular to the work as possible. Movement side-to-side while
tapping or when using a die will result in loose threads.
They may still work, but will result in a weaker fastening.
There are 3 types of tap for each size: taper (first), plug (second), and bottoming (last).
If you're going all the way through something, use the taper, run it through
until it doesn't cut, meaning you're reached past the tapered part.
As Eric mentioned, if it's a blind hole, you need then to run a plug tap into
it, same size, just tapered much less, reaching the full diameter much
cleser to the start. After the plug tap, you'd run a bottoming tap, which has
almost no taper. It will cut the rest out to the bottom of the hole.
Keep it wet with oil. Motor oil will work. I've drilled and tapped a number
of things while out cruising. You can tap aluminum, carbon steel, stainless
steel and cast iron with the same taps and system.
As to the size question, in addition to using the drill to fit the tap, taken
from the chart, my rule is if a bolt breaks or shears off, drill and tap to a
From Chris Smith on The Live-Aboard List:
I can't imagine not having the tap and die set on board. The other item
to take up space is my thread restoration tool set. It is basically a
set of long taper dies, and a set of hardened steel files that match
various thread pitches. This has saved numerous bolts from being
scrapped. Let's face it, no matter how well the majority of us
prepare, that one odd bolt that you don't have a spare for is invaluable
and has to be reused. The rethread kit has saved my butt more times
that I can recall.
From mung on The Live-Aboard List:
Examples of when the Heli-Coil
is the right tool for the job (as opposed to tapping a larger hole):
- Spark plug holes, because you need to be able to get the old
thread size back.
- Head bolts, it's real easy to strip out
an aluminum block with a steel bolt. Now, yes, you could
enlarge the hole in the head to use a bigger bolt for the
size of the tap you would have to use, but then you have
one oddball bolt in your engine. Better to put the
helicoil in and put the original bolt in, with the added
benefit of not being able to strip that hole again because
the helicoils are a lot stronger.
- Sending unit; they don't really come in any size you want,
so you want to keep the thread size the same.
Fixing a stripped threaded hole into a casting,
from Andrew Bebbington on Cruising World message board:
If you can't either tap a bigger screw, or drill right through and bolt,
then as a last resort put two-part epoxy cement (tradename "Chemical Metal"
in the UK) into the screw hole, rub the screw in thin grease and screw home.
When the epoxy sets, it'll hold all right. Usually it's still possible
to get the screw out, especially if it is stainless and has a hex head,
but you will be lucky to leave an intact thread behind.
Chris Caswell's "Plastic Fantastic"
"Easy to Make Plexiglas Holders" (bending and machining) by Dennis Angle in issue 2000 #2 of DIY Boat Owner magazine
From Richard on Cruising World
If you are going to do much cutting or machining of plexiglass,
ask your supplier to give you cast acrylic rather than the more
common and somewhat less expensive extruded acylic. The cast
material does not melt when cut. It's a joy to work with compared
to the extruded stuff.
From JMott on Cruising World
Try a laminate blade and a jig saw (the teeth set downward)
and go very slow to avoid melting the plastic. Apply tape to the
base of the saw to avoid scratches. It worked for me. Plexi shops
use a hollow-ground band-saw blade. Also to drill screw/bolt holes
in plexi, some shops will sell you a bit for $5 to do the job.
From RichardS on Cruising World
A sabre saw with coarse tooth blade running at low speed
works well. Too high a blade speed will melt the plastic.
A single speed saw can be controlled with a lamp dimmer just
like a lamp would be. Lower speed works better for metal cutting also.
The cut edges of the plastic can be "polished" with the adhesive
used to cement acrylic together. A smooth edge to start with by
filing or sanding helps a lot. I leave the protective paper on
the plastic for all of the fabrication, taking it off just at assembly.
From Nick Wigen on Cruising World
You should "polish" the edges with a little heat.
Enough to melt the sharp corners and edges but not enough to
distort the surfaces. It can be done with a propane torch
with a little practice. Use some of the scraps and hold the
torch well away. Once the rough edges turn shiny that's enough
heat. It's not too hard once you get the hang of it.
From Glenn on Cruising World
I have found that using a coarse carbon tipped blade in a
table or circular saw just melts the cut and leaves a huge mess.
If I move over to a fine-tooth plain steel blade, it cuts it
like butter, little chips fly off, no-melting, leaving a nice
clean cut surface. Last blade I bought was $6.50 at Home Depot.
Well worth the investment.
From Peter Linwick on Cruising World
I have done this for years, cutting new acrylics for hatches.
Use a router, double-sided tape your template to the
acrylic and rout around it. Flawless operation.
No chipping cracking or other problems.
From Steve Studley on The Live-Aboard List:
There is a special plastic cutting blade for circular saws ... it looks like
gritty sandpaper on each side. I've used the same blade for about 15 years.
The blade doesn't heat the plastic too much. Used it for corian, avonite,
lexan, pvc plate and pipe.
You can cut outside curves fairly easily, inside curves are a pain. ...
From Ray Mummery on the Morgan mailing list:
There is nothing special about drilling Lexan. If drilling material
thicker than about 1/4" it may be worthwhile to use a squirt bottle to
use a little water to cool the material, or drill slowly since you can
melt the plastic onto the drill bit if it gets too hot; same with
Plexiglas or Lucite. Both are somewhat brittle so be sure to have a
piece of wood behind the work if drilling in place or beneath if doing
on the bench.
Fasten Lexan or acrylic with non-countersunk bolts or screws;
countersunk heads will spread and crack the plastic.
Put finishing washers under the heads to spread the load.
Drill the holes oversize and caulk them.
Don't overtighten the fasteners.
Lexan is destroyed (becomes crazed and brittle) by exposure to solvents,
including gasoline and acetone. Some people said they had Lexan ports
badly damaged by spray or exhaust from mosquito control helicopters.
Polishing Lexan or plexiglass ports:
From Phillip Moyer on the IRBS live-aboard mailing list:
I own a Kawasaki Concours sport touring motorcycle and when I bought it it
had a cloudy almost milk-color plastic windshield. You could not see
through it. I used regular auto rubbing compound to rub it out and it
became very clear. That was several years ago and it is still in good
shape. Start with the most gentle and if that doesn't do it then work your
way up to the next heaviest grade. Mine did well with the least abrasive,
but took a couple, maybe three applications with soft cloth rubbing the
abrasive on and off with a clean one. Be sure to keep the buffing cloth
From Denece Vincent on the IRBS live-aboard mailing list:
A couple of other 'cheap tricks' you can try ...
a bit of toothpaste will tell you if you can reasonably restore clarity by
polishing. If it seems like that works then you may want to invest in a
better polish and go for it, but plain old toothpaste will clean and polish
a lot of stuff.
I also like to use an "Island Girl" product (on the boat and name escapes
me) to rejuvenate clear plastics. Even my badly crazed hatches were much
clearer after a good soak in this stuff and the pre-cleaner removed the haze
from the side ports easily.
From Rob/Florida Rigging on Cruising World
... clean with soap and water, do not use stuff like acetone
or similar cleaning agents, only use specified polishing compounds
when removing scratches.
From David Straton on World-Cruising mailing list
Never, ever, let anyone near Plexiglass (Perspex) with paint stripper.
From Doug on World-Cruising mailing list
Re: Acrylic (PLEXIGLASS) or Polycarbonate (LEXAN, MAKROLON):
Acrylic has a harder surface but there are polycarb sheet products
available with an abrasion-resistant coating applied to the surface.
Such as GE's Lexan coated materials, but its only a coating, so once
the coating goes ...
The polycarb coated product is very tricky to form without
crazing or bubbles showing up on the bends.
Acrylic is fairly easy to bend, form or fabricate and offers nice
clear bends. Acrylic also is easily polished, especially edges, where
polycarb doesn't polish up well.
Acrylic is more rigid than polycarb; way back in the 70's a lot of
dance floors were built from Acylic.
Acrylic is very tough and break-resistant, though notch-sensitive.
Hence, cracks can emanate from unfinshed mounting holes or rough
edges. Polycarb has a high degree of resistance to any impact, even on
unfinished mounting holes or edges, and is very close to
Acrylic is also cheaper than polycarb.
Acrlic has excellent UV resistance. Polycarb products don't, though
some are available with a UV coating; again it's just a coating and
causes problems in forming.
- Put some masking tape down.
- Draw your hole positions on the tape.
- Look on other side to see that you aren't going to hit anything.
- Tape a plastic bag to other side to catch all of the dust and shavings.
- Drill very slowly with an undersized bit in the center of the first hole position.
- Look on other side to make sure hole appeared where you thought it would.
- Repeat for rest of holes.
- Drill holes to proper size. Slowly.
But someone else says: to avoid cracking, drill a "dish" or depression first,
with a countersink or big drill bit, then drill in the center of that
with a small bit.
To keep nasty fiberglass dust under control, dab a little shaving cream
on the area before you start drilling.
Sawing fiberglass: use Fein Multimaster and HSS (high-speed steel) blades.
To keep nasty fiberglass dust under control, dab a little shaving cream
on the area before you start drilling.
Fiberglass molding article by Bruce Bingham in 11/2001 issue of Cruising World magazine
From Deborah Lloyd on the Morgan mailing list:
We had crazed lexan hatches. Ours are molded, completely
lexan with no metal holder and very expensive to replace. For a quick
fix a couple years ago that we have learned to love, we put a *very*
thin coat of epoxy resin on them, sanded it, then Awlgripped them
white. They look fantastic. We weren't sure it would work, but they've
held up perfectly. Of course they no longer are see-through. We like
that as we live in the tropics (Keys) but that may not be best for your location.
Gelcoat is a smoothly-finished, pigmented layer of polyester resin that
is on top of the fiberglass-and-epoxy/polyester hull.
SailNet - Don Casey's "Recovering the Shine"
Gelcoat is thin; don't rub it completely off down to the fiberglass.
Keep it hard, smooth, shiny, watertight.
- Wash off dirt and grit before it abrades the surface.
- Clean off stains (start with mildest possible way:
Bon Ami household cleaner (non-abrasive), then rag with solvent,
then commercial cleaner, then wax/cleaner, then
automotive rubbing compound).
For oil/grease/tar stain: kerosene or paint thinner,
then wash thoroughly with detergent and water.
- Repair scratches, dings, etc.
- Protect with non-abrasive wax (except on walking surfaces);
about 3 times per year.
Don't use automotive waxes which are formulated
for acrylic or alkyd auto finishes; use special
fiberglass waxes which fill in pores and screen UV.
But from Brett King on Cruising World message board:
Do not use wax or soap on any of the two-part paints, it just
makes them dull. Wash with ammonia and water. It will shine
for 10 to 20 years. Then sand and repaint.
- Every 5 to 10 years, paint.
For faded/dull gelcoat, try these (stop when one works):
- Rub with fiberglass paste cleaner.
- Rub with automotive rubbing compound.
- Wet-sand very lightly with 800 grit sandpaper.
From Leon Sisson on Cruising World
First, I read up on fiberglass repair in two or three of the
fix-up-your-old-boat books ("This Old Boat" by Don Casey,
and "The Boat Repair Manual" by George Buchanan).
I then bought the large gelcoat repair kit from West Marine (later
saw nearly identical kit in WalMart for about half the price),
an additional qt. of white gelcoat with catalyst, a tube of
tint (my topsides are sort of buckskin color), and a qt. of PVA.
I've discovered a couple of things that I don't remember reading much about:
Matching gelcoat colors was really hard for me.
It took a lot of patience, and I threw out several batches
after screwing up the color beyond recovery.
I tinted in approx. 8oz. batches (large enough to complete
my repair), and catalyzed in much smaller quantities.
For filler putty, I used tinted gelcoat thickened with
Cabosil (coloidial silica?). It worked great.
To get the air-inhibited gelcoat surface to harden,
I brushed on PVA mold release just after the surface
was stiff enough to resist brush strokes.
At some point in tinkering with the cosmetic appearance of the repair,
I paused to have a debate with myself about how many hours I was
willing to invest in exchange for what level of perfection on a 20
year old boat. Don't forget to have this discussion with yourself,
maybe more than once.
I wet sanded the repairs with 180 and 220, and the entire hull
from shear to bootstripe with 320, 400, 600 by hand.
I then power buffed with red rubbing compound using a
multi-speed 7" disk sander/buffer.
So far I'm really pleased with the results (and modest too!).
I'll probably power polish with fine white polishing paste before waxing.
From Roy Miles on Cruising World
Gel coat repair kits are available at marine stores.
First sand the base area with fine sandpaper, then clean with acetone on a rag
[but Janet aka RavenIV says "never use acetone to clean after you sand,
it can compromise the exposed resin. Instead either blow it clear or vacuum the area."].
Don't begin building up the gelcoat patch - first you need to practice getting
the color match. No matter what you do, however, it will never be exact.
Even if the color gets matched today, six months from now it will slightly
discolor with ultraviolet light exposure, making a small change in color.
If it's a small area, don't worry too much about it, just do your best.
Start blending the pigment with the catalysed resin, put it on a piece
of cardboard and let it kick off. When you get a feel for the correct
pigment blend, make a little extra and "putty" it on to the
affected area. Wipe off the excess while it's still "green"
or soft. Then lay a piece of saran wrap on top to seal off the
air (unless the instructions of the resin tell you it has a wax additive).
When the resin is good and hard, sand it down flush with the surrounding
glass using fine sandpaper. Then wet sand with increasingly finer wet-or-dry
sandpaper until you get to 600 grit. At this point you will have a difficult
time telling it from the original.
Then rub a little car wax on top to bring the shine up.
If you use epoxies [instead], you will need to paint over them to protect
from further ultraviolet degradation.
From Keven Sard on the Yacht-L mailing list
There are three big mistakes people make when doing gelcoat repairs.
BoatU.S.'s "Fiberglass Repair"
SailNet - Don Casey's "Repairing Gelcoat Cracks and Chips"
1) If you rout out the crack you will want to fill the area with some sort
of resin based filler. Make sure that when the filler is cured that you
de-wax the surface. Sanding to fair it out won't do it. You need to use a
de-waxer to take the blush off the repair. If you don't you run the risk of
the gelcoat not adhering or curing correctly.
2) Novices will always a) way overfill the routed area leaving a huge hump, or
b) way underfill the area leaving a trench. Personally I prefer to see a
trench since the hump will undoubtedly be haphazardly sanded and look worse
than the original crack. Remember that the filler will shrink slightly.
Don't be afraid to back off the catalyst a bit so that you have time to work
the area into a nice smooth repair. If you have never worked with resins,
make up a batch and practice on a piece of wood or Formica until you get the
hang of it. By the way if you have never used a Dremmel tool you might want
to practice with that too.
3) The color won't match. Remember that like paint, when the gelcoat cures
it will change tint slightly. When I worked in the repair shops we would
match the color as best we could, then smear a bit (without catalyst) onto a
nearby area and wait a minute or two. This will show you how close you will
be to the original color. Don't worry if it isn't perfect; it never is,
but the sun and salt will soon take care of that.
With that being said, I'll add one more piece of advice. If the cracks are
cosmetic, think about leaving them alone. I know boat owners want their
vessels to look pristine forever, but the fact is that cosmetic cracks are
inherent in gelcoat. You can't stop them from happening, and if you don't
enjoy working with resins and epoxy, and cabosil (micro glass beads) forget
about them. Soon you will find that they have plenty of company.
Gelcoat repair kits tested in 8/15/2001 issue of Practical Sailor
Resins (epoxy, etc):
From John Dunsmoor:
Polyester resins are laminating resins, they were designed to lay up cloth.
A finishing resin is also a polyester resin but has the addition of wax,
that will rise to the surface. When you use laminating resin you will
notice that the surface remains sticky, this is designed this way so
you can lay on another layer.
Progressive Epoxy's "Marine Epoxy Home Page"
Epoxy resin is an adhesive, it is made to stick to things.
A lot of the time when repair is done epoxy resins are the choice.
Now here is the rub. If I am working on a glass repair, and
grind down to fresh material I would normally recommend using
polyester resin rather than epoxy resin. I have found that
polyester sticks to polyester better than epoxy sticks to polyester.
Polyester will not stick to epoxy, if you do a repair in epoxy,
then you will have to do every repair on into the future with
epoxy because polyester will not stick to epoxy.
New construction. I paint a layer of polyester resin, thinned with
acetone on to fresh wood so it sinks in deep. Once this is done
the surface is basically a polyester surface and I laminate the
cloth onto the wood with no problem, never had a delaminating
problem with this method if the surface was fresh.
Epoxy resin is more expensive. I would not use WEST System epoxy.
I would drive to Fort Lauderdale and use Fasco epoxy.
I have used both on repairs and Fasco worked better than WEST.
Joe's Auto Marine sells Fasco, I am not sure who else does.
Be careful of high solids epoxies like Steel Flex, they can
be very very tough to sand. Bondo is not a marine product
and should not be used. It will suck up moisture like a sponge.
If you need to do some filling on a polyester repair, just mix
some resin with cabosil or micro balloons and you have
something the consistency of Bondo.
Same with epoxy, mix with the same fillers and spread away.
From people on The Live-Aboard List:
Instead of expensive filler from WEST/Gougeon, use diatomaceous earth (used in swimming-pool
filters; sands easily), powdered silica,
cab-o-sil, or pulverized lime (very hard to sand).
From Rusalka Mist
... [Radio] soon caught a direct hit from a pint of sea-water
coming in the main hatch. It did not work again during the crossing.
Believe it or not, all electronic circuits are completely waterproof.
It is the conductivity of water, especially sea-water, sitting across
the connections that makes them malfunction. The corrosive powers of
sea-water can also do terrible damage if left in place for more than
a few days. I took the plastic case off the machine off and ended up
with three circuit boards (a computer, the radio receiver and the
cassette machine), a buzzer and the loudspeaker, all interconnected
and sitting in the washing-up bowl. I washed and re-washed the whole
lot in several changes of cold, fresh water, washed and oiled the
telescopic antenna and the battery terminals, and rinsed out the
two halves of the plastic case. When I was convinced that there
were no more salt crystals lurking anywhere, I put all the parts
around the cockpit seats in the sun and carefully began to dry
everything with clean, absorbent kitchen paper. When reassembled
and then left overnight to dry completely, it all worked again perfectly.
This seems very bold at the time, "Electricity and water don't mix"
we are told. I have done this to many pieces of sensitive electronics
including Autohelm autopilots, digital watches and cameras.
It usually works, if the corrosion has not gone too far and if
you are careful not to touch any of the delicate adjustments.
All you have to do is remember how to put it all back together
again when it's dry!
From article by Clark Beek in 7/2003 issue of Sail magazine:
- Check obvious things: power, wires, fuses, switches, corrosion, connections.
- Take apart, separating out printed circuit boards.
- Check obvious things again.
- Look for cracked soldered joints.
- Wash the circuit boards; don't wash batteries, motors, speakers or displays.
Wash with fresh water, scrub with water and a little dish soap,
- Dry very throughly and for a long time.
Also sun-dry or put in oven at very low temperature.
- Put it back together and try it out.
Stainless steel maintenance/failure article by Ralph Naranjo in 3/2001 issue of Cruising World magazine
Stainless steel article by Steve D'Antonio in 6/1998 issue of Cruising World magazine
(data on more than 5000 materials)
"Metal Corrosion" article by Mark Smaalders in July/August 2001 issue of Good Old Boat magazine
"Drilling Stainless" article by Wayne Redditt in issue 2001 #1 of DIY Boat Owner magazine.
Keep stainless steel clean (rust-free), and polish it frequently.
From John / Truelove on The Live-Aboard List:
> 304 or 316 stainless: I am getting ready to
> purchase the steel for my solar panel rack and am
> wondering what the real-world difference is in
> the corrosion resistance of these two alloys.
I think 316 is the stuff to use. I made mine out of 304 7/8" ss tube. It
supports four 75 W panels. It's fine, but it rusts badly, just as the pulpit
rails do. If I do it over I'll use 1" passivated 316. My external chainplates
are passivated 316, and they *never* rust, but I'm always after the railings.
From Bruce Bowman on The Live-Aboard List:
Whatever you use, make sure the fastenings and the structure are the
same material. Mixing materials, even differing grades of stainless,
can invite corrosion in something that would otherwise be OK.
Summarized from "Rigging Lessons" article by Tom Zydler in May/June 2001 issue of Ocean Navigator magazine
Type 316 stainless steel is vulnerable to "stress corrosion cracking"; don't
use 316 for chainplates and other fittings.
Use other stainless steel alloys, or Monel, which are "immune to stress corrosion cracking".
Mostly summarized from stainless steel article by Steve D'Antonio in 6/1998 issue of Cruising World magazine
- Galvanized steel: "hot-dipped" usually has 3 mils of zinc; electroplated usually has 1.5 mils.
- 302 and 303 SS: crevice-corrodes freely; rusts from saltwater; never use below waterline.
- 304 SS: somewhat greater corrosion resistance than 302 and 303; rusts from saltwater; never use below waterline.
- 18-8 SS: surgical stainless; similar to 304.
- 304L SS: better than 304 for welding.
- 316 SS: much greater corrosion resistance than 304; 85% as strong as 302 or 304; use above water; if for shaft protect with zinc.
- 316L SS: better than 316 for welding.
- 321 and 347 SS: good for welding; use above water.
- Aquamet and Aqualloy: SS's for shafts; corrosion-resistant and weldable but expensive.
- SS needs oxygen to remain stainless.
- Welding SS (other than "L" versions) creates zone of mild steel around the weld.
From Mark Mech on The Live-Aboard List:
The key to drilling stainless steel is first: a good bit, don't even attempt it with
The second most important thing is to drill at a constant speed that
doesn't overheat the metal. This is the most important reason to lubricate
(you could use water); if you overheat the metal by either going too fast or
too slow, it will "work harden" and you will toast the bit. If it is a deep
hole, you may not get the bit back because it will gall in place then break
off or get REALLY stuck.
So keep it moving, keep it wet, and keep it sharp.
Also: "use Moly-Dee cutting fluid".
I enlarged some holes in stainless steel: bucket of water to cool
work-piece and bit after every 15-30 seconds of drilling,
vegetable oil as cutting fluid, and keep a steady feed pressure of the bit
on the work-piece.
From "Drilling Stainless" article by Wayne Redditt in issue 2001 #1 of DIY Boat Owner magazine:
- Use low speed.
- Feed bit into material as fast as it will go; press hard.
If using a bit smaller than 1/4", you should press hard
enough to make the bit flex.
- Center-punch to keep the bit from wandering when starting.
- Use lubricant.
- Don't stop or slow down until hole is finished.
- Best bits are HSS jobber bits, not titanium oxide coated or special tip grind.
- Drill pilot holes.
- Using a drill press is best.
- If bit turns blue while drilling, it's turning too fast or is damaged.
Epoxy onto steel:
- Clean the metal.
- Sand with coarse sandpaper.
- Thin coating of epoxy.
- Sand again while epoxy is still wet.
- Put other piece onto epoxy.
Good articles in May/June 2000 issue of Good Old Boat magazine
From articles in May/June 2000 issue of Good Old Boat magazine
- Much of the "bronze" sold technically is brass (contains zinc, and often lead).
Real bronze is copper and tin. Brass is easier to machine.
- Stainless steel is stronger and tolerates aluminum,
but bronze doesn't rust or crevice corrode.
- Deterioration of bronze is signaled by white powder or flaking metal.
- Many different alloys of bronze: silicon bronze (alloy 655),
manganese bronze, HT bronze, etc.
- Many different alloys of brass: free-cutting yellow brass (alloy 360),
a red brass (alloy 230), etc.
From Yahoo Answers:
The color terms yellow and red are American terms referring to the composition of the brass.
Yellow brass is 33% zinc and 67% copper.
Brass goes from dark reddish brown to light silvery yellow depending on the amount of zinc.
The more zinc the lighter the color. Red brass is really not brass as it is
an alloy of copper, zinc, and tin. It is also called gunmetal.
Any brass whether yellow, red, whatever, will be fine for a fuel system.
You should always uses silicon bronze for below-water fittings and no brass.
No one that I have ever seen makes bronze nipples. Bronze is cast and brass pipes
can be extruded. Bronze does not extrude well into pipe form thus no bronze nipples.
There is no need for either red brass or bronze in a fuel system.
Moeller (used to be Tempo) is one of the largest suppliers of marine fuel fittings
and they are all brass. ABYC does not specify anything other than brass either.
There are two kinds of brass on the market, yellow brass and red brass.
Yellow brass is made from a variety of metals such as zinc, tin etc.
This gives the brass a yellow appearance and has a life expectancy of somewhere
between 10-25 years. However, red brass when compared to yellow brass has a
reddish look due to the high copper content (80-85%) and has a life expectancy
of 50-100 years. Note: Life expectancies assume clean water and environmental conditions.
Harsh water and/or environmental conditions may shorten the life expectancy of brass products.
Machinable modern materials that won't corrode like metals or woods:
Can't glue or caulk or seal an edge against it, except maybe
with special glue and tools from manufacturer.
- UHMW plastic.
- Garolite / G10.
Easier to cut/sand/paint than metal/wood/fiberglass,
but must paint to protect it from UV.
- Wood/plastic composites:
- Arborite ? (Or maybe it's a veneer over composite, like Formica ?)
Some of these materials (such as StarBoard) are too soft/porous for applications (such as galley counter) where they
might get chipped or stained.
From Mike on Gulfstar Owners mailing list:
Be careful with StarBoard out in direct sunlight. UV degrades it over time and any stress points will split.
I installed PVC (StarBoard) handrails instead of teak. After 4 years on deck, they all cracked at the screw points.
Manufactured fibers (summarized from article by Hugh Horton in Epoxyworks #16 Fall 2000):
Strong in one direction only.
- Carbon fiber: strong in tension, strong in compression,
fairly easy to abrade and shape. But fibers are noxious,
edges are sharp, dust is irritating and noxious, black color
gives heat buildup.
- Kevlar braid: strong in tension, weak in compression,
hard to abrade and shape. Easy on the skin.
SailNet - Tom Wood's "It's Winch Servicing Time"
SailNet - Tom Wood's "Keel Shield"
"Wooden Rails Made Easy" article by Gary Grinnell in issue 2000 #3 of DIY Boat Owner magazine.
Batteries not holding a charge:
- Bad charging system voltages ? Bad float voltage ?
- Bad cell in battery ?
- Unequal acid gravities in cells of same battery ?
- Loose/corroded wires/connectors/switches ?
- Intermittent load ? Disconenct battery from all loads and see if it stays charged.
- Do load test of battery.
From John Dunsmoor:
> I'm confused about when I should use grease,
> spray WD-40, or teflon lubricant.
> For example, my dinghy davits have sheaves in them.
> What should I lubricate them with ?
> How about the blocks in my running rigging ?
WD-40 is a good all around spray around saltwater, more of a rust preventer
and general light lubricant, but not the same as a grease. Grease is a heavy
lubricant that sticks to parts, like wheel bearings and winch bearings.
But not as something you would put in a transmission per se. A gear box
needs a lubricant that flows, so does an engine.
Most running rigging, sheaves use no lubricant, nor should they.
These are made with Rulon or Nylon bearings that are self-lubricating.
If you were to use grease, teflon or waterproof, then what happens is that
the "grease" gets full of grit, dirt, salt crystals, grime and this forms
an abrasive and destroys the bearings. Mostly with things like running rigging
blocks and such, a good dose of fresh water once in a while to keep them
clean is the best bet.
Davit sheaves ... depends whether or not they have bearings, bushings or what.
The best bet is to know what the manufacturer recommends.
From Rob Homan on the Morgan mailing list:
Subject: One way to fix a polyethylene water tank.
Yesterday I was talking to one of our fellow sailers in a boating store,
and he said that he had worked in the RV industry for quite a while and
we had been discussing my dilemma with my water tank, and the fact that
it appeared that there was no way to buy an OEM replacement.
He suggested that I go to "Camping World" and get a Polyethylene Plastic
Welding Kit. Well, I did. It is named just exactly that. It is
manufactured by Kennedy's Enterprises, PO Box 82544, Bakersfield, CA
I "welded" my tank today using their product, and below I will describe
My tank that resides below the forward V-Berth had a crack at the rear
center bottom behind the outlet nipple on the tank. The crack was about
3 inches long and was one that allowed a very slow leakage of water.
I cleaned up around the area and then took my Dremel tool with a very
small router bit and followed the crack routing a groove into where the
crack was. I drilled stop holes in both ends of the crack. I cleaned
all the bits and pieces away from the area and then took the "welding
rod" and laid it into the groove and started heating up the rod to melt
it into place with a rather hot "heat gun". I followed the directions
on the package which called for melting the rod an inch at a time. You
have to let it cool a little and do this while holding this very still.
The objective is to get the welding rod as deep as you can into the
crack. During this whole time you have also been warming the
surrounding areas of the tank, and so then you take and heat up the
larger plastic stick melting it and letting the melted plastic roll over
where you welded in the smaller rod. The second stick provides a seal
that covers over the work area and closes up any tiny holes that may be
The whole process didn't take but about 30 minutes after I pulled the
tank out and found the crack in the tank. I have to warn you ... If you
choose to use this product, do not touch any of the area you have worked
on for a couple of hours ... this stuff really holds heat and it will
stick to you. I found out by being too curious.
I'm going to let the tank sit over night and "cure", then tomorrow I'm
going to put a second "sealer coat" on it and let it cure again. Then
I'm going to put it back in its molded cradle and fill it with
water ... and then I'll come back and let you know if this
product works as it is supposed to.
Repairing plastic: maybe use fiberglass cloth and G/5 Adhesive from
Diving on your boat,
summarized from "Below the Waterline" article by J. J. Stives in July/Aug 2001 issue of Ocean Navigator magazine:
Sometimes, it is best not to dive on your boat.
Alternatives: wait for better conditions (daylight, calm, etc),
wait for help, get a tow, get professional diver, get boat hauled out.
It may be best not to dive on your boat if you haven't used your SCUBA equipment in years,
if you're not in good shape, etc.
Planning list for a dive:
- Survey problem from on board as much as possible.
- Pick tools (minimum: wire cutters, diagonal cutters, knife, pliers, screwdriver).
- Decide how to enter and exit the water.
- Will boat be safe while diver is in water ? What are winds, currents, hazards, depths, sea room ?
- What will happen when problem is solved ? Will boat sail/blow away from diver ?
- Consider using dinghy as platform for a partner and tools.
- What are water conditions (temperature, visibility, depth, current) ?
- Decide level of clothing diver will need (minimum: hand and foot protection).
- Prepare gear.
- Prepare tools (all should have breakaway lanyards).
- Hook up safety lines (diver should be able to cut them if needed).
- Check for traffic, display diver down flag, broadcast alert on VHF, light up the boat.
- PFD's on everyone; BC on diver.
When in water:
- Watch out for motion of boat.
- Watch out for recoil when lines are cut or propeller is freed.
- Nets, sheeting, fabric, fishing line are very dangerous; don't get tangled.
- First, evaluate the problem, inform others of problem and plan to solve it, get agreement.
Then execute the plan.
From Doug Barnard on The Live-Aboard List:
Re: Securing shelving to fiberglass hull:
[... epoxying wooden blocks to the hull and screwing shelving unit
to these ... ]
For a first-timer, I'd suggest going with West Systems, and getting their
book. It's available at most marine stores. At about half the price, try
the Basic No-Blush at www.epoxyproducts.com . You can still use the West
methodology, just follow the different mixing instructions. I wouldn't
go with the cheaper polyester resin, as it's tough to use, very
temperature-sensitive, and will fume you out of the boat as you apply it.
For a super-strong installation, get some of West's microballoons (or
use very fine shop sawdust, if you're cheap like me) and mix up a
peanut-butter-like paste. Use it to glue the block to the hull, and
apply with a Bondo squeegee to make a nice rounded fillet between the
hull and the block. Still want it stronger? Apply some fiberglass cloth
over the fillet, and give it a few coats of epoxy. Use disposable
bristle brushes and surgical-type gloves. No air bubbles allowed!
I've had good luck (so far) with gold-anodized drywall screws, much
cheaper, easier to use and stronger than solid brass screws. We shall
see about how well they hold up, but I'm in a very dry climate, YMMV.
They're so cheap, I can always replace them with solid brass, and only
be out a few bucks.
Probably the easiest way to mount the shelves is to attach the blocks to
the shelves first, goo them up, and then wedge the whole deal into place
with whatever's handy. After the epoxy's kicked off, but before fully
cured, careful unscrew the shelves and remove. You can then scrape away
any extra epoxy, much easier (and cleaner!) than sanding. Mix up another
batch, and do your fillets. You should treat the wood (paint, varnish,
whatever, at least Thompson's Water Seal) fully before re-attaching your
From SailNet - Tom Wood's "Mounting Deck Hardware":
- As you take complicated things apart, take photos so you can
figure out how to put them back together later.
- From Tom Neale: bottom-painting is easy; bottom-sanding
is worth paying someone else to do.
- Sanding with waterproof sandpaper: use it wet, wash frequently
to prevent clogging, add a little detergent to lubricate.
- Before working with fiberglass, put a barrier coat
of lotion on your hands and forearms.
- Strongest and most corrosion-resistant fastener materials
are Monel and T316 stainless steel.
- Best screw-heads: square drive (Robertson).
[From STsFinback on the IRBS live-aboard mailing list:]
Fill drive hole with bar soap [or grease] before painting over, or else the
paint will fill it. [Same for painting over Allen-heads.]
- From Bruce Duckett in July/August 2000 issue of Good Old Boat magazine:
To enlarge a hole with a hole saw, plug the existing hole with wood and then
saw using center of plug as center of new hole.
"Consider lashing or taping a new piece of gear in place and using the boat
that way for a week before bolting it down permanently."
From Sandy Gurnell:
To avoid dropping a screw into the bilge, tie a thread to it.
Screw it in most of the way, then cut or snap the thread.
See Periodic Maintenance
section of my Lists for Operating a Boat page.
"Hit on it until it breaks, then back off one hit."
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