not sure what i should use epoxy resin or poly resin

bingobongo

Cadet
Joined
Jul 3, 2006
Messages
6
i am almost ready to start applying mat and woven on bulkheads and stringers, i am a little confused on what resin i should be using on the mat and woven,are you only suppose to use poly when applying mat and woven. i was going to go the west system route,but boy they sure are expensive i have checked out boat projects on shareaproject.com and a lot of people used poly and the price for it was very cheap compared to doing it with west system epoxy i am working on a 22ft runabout and i will need a lot of resin,im sure i will need gallons of this stuff,calculating what it would cost me with west system does not fit into my budget are there any other good brands of resin that are not so expensive and work well,
need some help here guys thanks . be patient with me guys it wasnt to 4wks ago i found out what a stringer was
 

OperativeK

Petty Officer 2nd Class
Joined
Apr 21, 2005
Messages
154
Re: not sure what i should use epoxy resin or poly resin

If you go with the West System you won't be dissapointed, it is epoxy resin and when it dries it looks like glass almost. I am using it on a repair from a tree stump problem and I can honestly say I am really glad I went with it. However if you are filleting stringers you could go with a polyester resin or other known as fiberglass resin. It is the cheapest. I used it to put in new seat bases and it was fine. Just make sure you paint it and keep it safe from UV, else it cracks and shrinks.
 

BillP

Captain
Joined
Aug 10, 2002
Messages
3,290
Re: not sure what i should use epoxy resin or poly resin

There's nothing magical about epoxy...it glues, gap fills, adheres better and is stronger than polyester. In terms of strength it is approx 30% stronger when measured as lb to lb. This means you can make a lighter product. If you prep correctly the poly will do everything you need it to and for a LOT less money. If the surface is difficult to clean and prep, epoxy is a better choice...if you are lazy and dont' want to do a thorough prep, epoxy is better.

I'd use polyester laminating resin (not finishing resin) and don't worry about it. If you use epoxy it takes a special mat. If you use epoxy with the same mat as poly it will be impossible to wet out...leaving a dry and weak layup. Poly can use any type mat. Woven works with both resins...it's just the mat that needs to be different.

For what it's worth, the last boat project I did was with epoxy (I used epoxy because pressure treated wood). It took 13 gals to do a 100% "gut and rebuild" of a 17' outboard. I used a generic epoxy that was less than half price of WEST brand. Several yrs later now and it still looks like the day we first splashed it.

Man, the spell check here scrambled my message!
 

BillP

Captain
Joined
Aug 10, 2002
Messages
3,290
Re: not sure what i should use epoxy resin or poly resin

oops...double post.
 

Kevin70

Petty Officer 1st Class
Joined
May 24, 2006
Messages
342
Re: not sure what i should use epoxy resin or poly resin

If the expense is an issue, remember that boats have been built with polyester resin for decades. If you seal up the plywood COMPLETELY, you can get a good 40 years out of that stuff. On the few parts of my boat that were sealed properly, the plywood still looked brand new after 22 years. And, a five gallon bucket of it is about $110 as oppose to $400 - $600 for the same bucket of epoxy.
 

bingobongo

Cadet
Joined
Jul 3, 2006
Messages
6
Re: not sure what i should use epoxy resin or poly resin

thanks for all the great info guys keep it coming looks like i will go with the poly
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: not sure what i should use epoxy resin or poly resin

Epoxy is great stuff, it just does more than you need it to do, so it's hard to justify the price.
 

epresutti

Chief Petty Officer
Joined
Aug 14, 2001
Messages
465
Re: not sure what i should use epoxy resin or poly resin

bingo,

I rebuilt using epoxy, I bought about 15 galons total for an 18 ft. walkthrough, I had gutted down to the shell. I puchased from fgci.com, they are a Florida distributor but will ship anywhere. They were a lot less expensive that West. Heck you can buy 55 gal drums from these guys. There are many Florida builders that use their products.

If I had to do it again, I think I would go with poly and spend the time preping, a lot less expensive and since I was replacing everything, I could be sure that I would get good bonds to all surfaces without too much worry.

Peace.

Ed.
 

lagoon bandit

Seaman Apprentice
Joined
Nov 24, 2005
Messages
38
Re: not sure what i should use epoxy resin or poly resin

I am a novice at boat restoration but here my $.02...
I see the benifits with epoxy but there is nothing wroung with poly.
I am doing my rebuild with both epoxy & poly I just need to plan a head because ploy dose not stick to epoxy
I think this will save lots of $$ and get the job done right
 
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