Polyester Resin??

[P man]

Ive used up all of my East System, and need to restock. Right now Im just doing cosmetic as well as low strain structural glassing. I would like to just use cheap polyester resin for financial reasons . My only problem is that later on Im going to need something to redo my wooden boat. Can I apply a poyester coat on top of an East System finish???

ps Does anyone have an opinion on what the best cosmetic filler is in terms of easy sanding?? Ive been using cotten fiber cause its all I got and im sick of trying to sand the stuff lol

[Bob T]

Do you mean WEST SYSTEMS epoxy.If it is, they have great tech manuals ....they also have a web sight.I'm sure they'd answer all your questions.I'd be VERY surprised if you couldn,t use polyester resin over it cuz you can gelcoat over their product and gel is basically just polyester resin.Use micro ballons for a sandable finish.Hope this helps.BT

[Bob T]

I was out in my garage glass'n and it hit me....If the surface you're bonding to has cured,you are relying on mechanical bond rather than a chemical link.You should be able to use polyester resin with out issue.BT

[Gerben]

Never heard of East System. If indeed it's west-system it's epoxy.

Don't apply polyester over Epoxy, doesn't work.

Gerben

[Techno]

Gellcoat is pretty easy to brush on and to sand. I've used it on my dash and the stress cracks that were ground out.
Could also use many of the fillers for the epoxy. Microballoons and spheres and all that.
I've heard not to apply one resin over the other and haven't tested it yet but I don't see why they won't bond both ways. As long as they are cured plastic and have scratch for a bond then it should stick. Like I said I haven't tested it.

[P man]

Thanks for the replys.
Im supprised some of you dont know of East system. Ive only built one boat with it but it worked very well.
Any other input is appreciated

[Bob T]

West system's manual detail how to apply gelcoat over their product.Gel is polyester resin so I don't think it 's a problem.I hope I'm not missing something as I'm about to gel over a pad I laid up with epoxy.....Someone please tell me if I'm missing something.Would adding pigment to the epoxy as a final finish serve the same purpose?BT

[Techno]

I tried the pigment for eposy and didn't like it. Maybe I did somthing wrong.
Besides epoxy sucks for sanding. Compared to gelcoat it's like 3 times harder to do.