I was reading one of glassdaves tutorials, (filling holes in 36 cig dash) he said, glass a sheet as a backer then make a plug and use poly resin with west 404 filler. I was looking through a catalog and saw there were alot of choices for different epoxy resins but only one choice for poly. Is one better than an other? If I use epoxy on the whole process, is it ok? Or should I use the poly all the way? Does it matter what the factory used in original layup?

There is nick/ gouges around the bow loop, is resin/404 filler the best way to fill these nicks in to and strong enough for the abuse?

steve

PM Dave, He will set you straight... It would take me to long to tell/type what I learned from him... He is a great guy!!

Epoxy resin is superior in strength & non shrinking qualities. However in general, if you start with epoxy you need to pretty much stay with an epoxy, as the mek in the poly stuff can soften the epoxy. There are a few tricks to getting around this to some extent, but unless you have done this stuff before I would recommend not going the that route.

In short, If you are going to use paint to finish then epoxy is fine and will give you some extra strength, otherwise if you plan to gel then it would be easier and a bit faster to use polyester resin & Mek hardened products rather than epoxy based..

Jamie / Lakeside

It is always a good idea to stick with the materials that are used by the manufacturer.

Most of todays pleasure boats are laid up using either polyester or vinylester resin systems. Luckily these two systems are compatible with each other, polyester being the cheapest.

The severity of the damage will determine the proper way to repair it. If it is a large/deep gouge then you will need to prep the area and build it back up in layers, especially in a structural application. If it is simply a cosmetic problem, fill it, blend it and carry on.

+1 on all that. If its structural, epoxy is the best way to go but for cosmetic repairs on the do-it-yourselfer level you will have an easier time using poly's. Use a good quality resin and 404 from West but you may need a light filler as a skim coat to take care of any porosity. Are you using paint or gel for color?

http://uscomposites.com/polyesters.html


Fast Fibers welcome to the site. Are you in the glass biz? Feel free to jump in any time we got some good tech knowledge here and can always use more.

Thanks GlassDave, I am currently as senior in Plastics Engineering Technology in Manufacturing. My Education was driven by my love for composites and powerboats alike. I hope that I can offer some good advice here and also learn from the veterans of the site.

cool, you have access to some great minds here (and some not so great ones lol)

Thanks Dave...........

so if i use West systems Epoxy and plan on spraying gel over it will this cause a problem..

The best thing you can do is avoid mixing epoxies and esters. Like I mentioned before if your boat wasn't made with epoxy there is no reason to use it for your repair. Not to mention it is more difficult to use. Vinylester has similar characteristics to epoxy and will not conflict with the gelcoat, plus its cheaper