Resin identification? help

[Whaaaaat]

Helping a friend with a commercial fishing boat. Have quite a few areas built by previous owner that are delaminating. Most around the cabin wich is roving over foam core. Most of the things glassed into that are delaminating. Is there a way to tell what resin they used, poly, vinyl, or epoxy? So our repairs will not also delaminate. Thanks

[XstreamVking]

Only safe bet with an un known mix of resins is to use epoxy. Commercial boat is likely poly, imo. You could grind back an area and apply some poly resin and glass and do a pull test. Leave a glass tab sticking up and after cure, grab that with some vice grips and see how hard it is to pull off and see where it breaks. Should tear and come loose leaving some of the new glass behind. If it pulls off cleanly, getting no adhesion, then epoxy is next.

[tunnels]

Helping a friend with a commercial fishing boat. Have quite a few areas built by previous owner that are delaminating. Most around the cabin wich is roving over foam core. Most of the things glassed into that are delaminating. Is there a way to tell what resin they used, poly, vinyl, or epoxy? So our repairs will not also delaminate. Thanks

Preparation of any surface before glassing is a really really very important issue and yes if it was a commercial build its bound to be polyester ! so from here out doing rebuilding Epoxy is your best safe guard !! But all of the surfaces you are sticking to will need to be ground with a really coarse disc !16 grit if you can find them 24 grit maybe but nothing finer! Making the surface rough and the old glass fibers stand out is the key ! physical bond and well as chemical .

[Whaaaaat]

Preparation of any surface before glassing is a really really very important issue and yes if it was a commercial build its bound to be polyester ! so from here out doing rebuilding Epoxy is your best safe guard !! But all of the surfaces you are sticking to will need to be ground with a really coarse disc !16 grit if you can find them 24 grit maybe but nothing finer! Making the surface rough and the old glass fibers stand out is the key ! physical bond and well as chemical .

If it was my boat it would be epoxy, but it's gonna get poly. The problem spots I looked at today after peeling everything with a screw driver look like they were not prepped, the base layer was left to dry and they laid up over it without grinding. We got it ground with 24. Hopefully it will stay stuck this time.