I'm not a boat builder (but you guys do amazing work), I am planning on renovating the bathroom in my travel trailer in the near future and I want to put old barn siding on the walls in the shower. I thought who would better know how to waterproof wood (or anything else for that matter) than people who build wood floating things that in theory don't leak?
I've done a lot of reading and research and I had read somewhere once marine epoxy was about the best there is in waterproofing however, it seems like it' s 1 part science, 1 part alchemy and 2 parts mystery. There are some clarifications I need before I understand how this works.
*Good epoxy is a fairly thick honey like substance that turns to a plastic like substance filling all seams, small gaps and making the object waterproof?
Epoxy can also be a glue that will bond wood, metal, some plastic, fiberglass. Anything else?
Heat cures epoxy and will also "uncure" it? Would shower water be a problem since it usually runs 99- 105 degrees F?
Not all epoxy will be clear when it dries.... is there one or two that will be clear?
I should use a clear coat overtop of the epoxy to protect it from heat and possibly sunlight ( there are no windows in the bathroom so I'm assuming this won't be an issue.
Epoxy is a mix; a resin and a hardener.
The easiest is a 1:1 ratio (less guessing).
Fiberglass cloth is a thin fabric like material that can be bonded to wood for added strength and additional waterproofing.
I've read conflicting reports on epoxy application
some say roll or brush a thin amount on the wood but if it's honey like that seems a bit untrue... when I think of thin I think of cheap watery paint. Once it has cured (a few days -to a week, I should sand the epoxy, wash it with soap and water and add another coat of epoxy. Or I should wait to sand until after the last coat but before the clear top coat..... which is better? How many coats of epoxy should I use?
What clear top coats are good over epoxy and waterproof?
questions for the epoxy experts
Moderators: Bill Edmundson, ttownshaw
Re: questions for the epoxy experts


Don't be afraid to attempt anything. You might surprise your self in the attempt.
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Bon Voyage-"Wild Flower" 40' house boat being built
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32' Supper Huck-in design
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Bon Voyage-"Wild Flower" 40' house boat being built
14' Mr John-being built
32' Supper Huck-in design
Rod H
Re: questions for the epoxy experts
When I have the money I will definitely buy those books.
This whole fiberglass cloth stuff really has me thinking.... didn't know it could be bought as a cloth. Would it be possible to fiberglass and encapsulate the exterior of a trailer (before installing windows and doors) just like a boat then paint the exterior?
Also, can fiberglass and epoxy be done in segments? For instance, I live in my RV so I have to do one room at a time back to front. Which means I have to do the exterior one section at a time as well. I was planning on doing some kind of vetical wood siding but I'm worried about the additional weight.
This whole fiberglass cloth stuff really has me thinking.... didn't know it could be bought as a cloth. Would it be possible to fiberglass and encapsulate the exterior of a trailer (before installing windows and doors) just like a boat then paint the exterior?
Also, can fiberglass and epoxy be done in segments? For instance, I live in my RV so I have to do one room at a time back to front. Which means I have to do the exterior one section at a time as well. I was planning on doing some kind of vetical wood siding but I'm worried about the additional weight.
Re: questions for the epoxy experts
yes you could do this but it does add weight how much weight I couldn't say. And epoxy and fiber glass cloth is expensive not to cost effective but you could use it in this manner :roll:http://www.glen-l.com/supplies/epoxyindex.htmlCuriouser wrote:When I have the money I will definitely buy those books.
This whole fiberglass cloth stuff really has me thinking.... didn't know it could be bought as a cloth. Would it be possible to fiberglass and encapsulate the exterior of a trailer (before installing windows and doors) just like a boat then paint the exterior?
Also, can fiberglass and epoxy be done in segments? For instance, I live in my RV so I have to do one room at a time back to front. Which means I have to do the exterior one section at a time as well. I was planning on doing some kind of vertical wood siding but I'm worried about the additional weight.
Don't be afraid to attempt anything. You might surprise your self in the attempt.
http://www.facebook.com/Home.Made.Boat.Building
Bon Voyage-"Wild Flower" 40' house boat being built
14' Mr John-being built
32' Supper Huck-in design
Rod H
http://www.facebook.com/Home.Made.Boat.Building
Bon Voyage-"Wild Flower" 40' house boat being built
14' Mr John-being built
32' Supper Huck-in design
Rod H
- Andy Garrett
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- Location: Nampa, Idaho
Re: questions for the epoxy experts
I'm no expert, but if the wood has a coarse texture with lots of crevices, you should select a thin epoxy with no amine blush (more on this in a second). If it is fairly smooth, go with Poxy-Shield which you can buy right here. Do at least two coats.
The reason to avoid the amine blush with coarser wood is because that blush has to be washed off before the second coat. The blush itself is a waxy, sometimes sticky film which occurs on the cured surface of most epoxies. It makes it seem like the epoxy is not quite cured, but that is not the case. If the wood is very porous, it'll be tough to get the film and wax out of the crevices, and the second coat won't bond there very well.
I have had good success cleaning the blush with alcohol.
Good luck with your project.
The reason to avoid the amine blush with coarser wood is because that blush has to be washed off before the second coat. The blush itself is a waxy, sometimes sticky film which occurs on the cured surface of most epoxies. It makes it seem like the epoxy is not quite cured, but that is not the case. If the wood is very porous, it'll be tough to get the film and wax out of the crevices, and the second coat won't bond there very well.
I have had good success cleaning the blush with alcohol.
Good luck with your project.
Andy Garrett
Perhaps the slowest Zip build in Glen-L history...
Perhaps the slowest Zip build in Glen-L history...
- Mr Hot Rod
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- Contact:
Re: questions for the epoxy experts
Here are some rough weight estimates for fiberglass cloth applied at a 50/50 glass/resin ratio :Lowka53 wrote:Yes you could do this but it does add weight how much weight I couldn't say.
- 7.5 ounce = .104 LBS/SQ.FT (3.32 LBS per 4'x8' panel)
10 ounce = .140 LBS/SQ.FT (4.48 LBS per 4'x8' panel)
Source : Figure 8-14, Page 75, Fiberglass Boatbuilding for Amateurs by Ken Hankinson.
- 7.5 ounce = .104 LBS/SQ.FT (3.32 LBS per 4'x8' panel)
Here are some photos of the project :
We completely rebuilt the cabover structure.
The cabover bottom skin was built by laminating some 10 ounce fiberglass cloth to a sheet of 3/8" exterior
grade plywood.
____________________
Paul Kane
Kane Custom Boats Ltd.
Chelsea, Quebec
Building the Glen-L Hot Rod : http://www.kanecustomboats.com
Glen-L Boat Video Directory : http://www.kanecustomboats.com/pages/vi ... ctory.html
Re: questions for the epoxy experts
My two cents:
DO NOT put barn board in a bathroom. Bathroom equals moisture. Barnboards equal uneven surface (even if you fill it with epoxy!) ......
MOLD MOLD MOLD !!!!
That is why most kitchen and bath surfaces are very smooth!
SS
DO NOT put barn board in a bathroom. Bathroom equals moisture. Barnboards equal uneven surface (even if you fill it with epoxy!) ......
MOLD MOLD MOLD !!!!
That is why most kitchen and bath surfaces are very smooth!
SS
Re: questions for the epoxy experts
I'm really not sure why some of you have such an issue with blush between every single coat of epoxy you apply. Lay another down before the first one is completely cured and you will have no blush.
It's as simple as that!
It's as simple as that!
Bill
TNT Build, ... On Going, ... http://tinyurl.com/abmae64
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TNT Build, ... On Going, ... http://tinyurl.com/abmae64
The Freebie Zip, ... On Going, ...http://tinyurl.com/at3udss
Super Spartan Build "Miss Tripindicular", ... Completed, ...http://tinyurl.com/b488wsz
Re: questions for the epoxy experts
Another possible concern with glassing solid barnboard.
First note that I have absolutely no experience (yet) with fiberglass, but I have a lot of experience with wood.
Wood is hygroscopic - solid wood will expand and contract (across the grain) as moisture and humidity levels change. Plywood doesn't because of the cross banding of the grain.
Unless the solid barn board is completely encapsulated, there is at least a theoretical - I think think real - risk of the wood's expansion and contraction leading to problems with the fiberglass surface - separation from it and/or cracking of the FG.
I might be entirely wrong, of course.
First note that I have absolutely no experience (yet) with fiberglass, but I have a lot of experience with wood.
Wood is hygroscopic - solid wood will expand and contract (across the grain) as moisture and humidity levels change. Plywood doesn't because of the cross banding of the grain.
Unless the solid barn board is completely encapsulated, there is at least a theoretical - I think think real - risk of the wood's expansion and contraction leading to problems with the fiberglass surface - separation from it and/or cracking of the FG.
I might be entirely wrong, of course.