Hey Kevin! Big fan here and I’ve learned quite a bit off your tech video and articles. I’m working a 1983 Toyota Pickup restoration. I purchased a replacement fiberglass bed for the truck and had some issues priming the raw mat fiberglass (no gel coat) on the underside of the bed. I want everything to be clean, durable and maintenance free under the bed so my plan was to shoot the Eastwood epoxy primer and then spray it with Raptor Liner. Easy, right?? That’s what I thought, but it didn’t turn out good at all…
Here’s what I did:
1-The underside of the bed (a raw fiberglass mat surface) was sprayed with a black acrylic rattle can paint (that’s what the bed builder told me) so I decided to scuff it pretty good with 80 grit and then went back with SEMsolve to give it a good cleaning
2-After letting it dry out for a few hours, I shot two medium coats of Eastwood Epoxy primer with a 45 minute flash between coats
3-I then let it sit for 5 hours before I shot the Raptor Liner.
I left it in the shop for a few days while I did some bodywork on the cab, after about the 4th day I noticed the Raptor Liner bubbling up. Upon further inspection, I discovered that I could completely peel back the Raptor Liner in large sheets with no problem. The epoxy and what was left of the acrylic came off with it as well so I was down to completely bare fiberglass. It seems like the Raptor Liner bit into the epoxy, the epoxy bit into the acrylic and then the acrylic “let go.”
At first I thought that it was likely a compatibility issue with the acrylic so I prepped a couple small areas again (no acrylic present) and shot them with epoxy. After about a week, the epoxy is still rather soft and I can scratch it off with my fingernail.
I can affirm that the epoxy itself didn’t go bad since I’ve had no problems with the cab that I sprayed during the same session.
Note: epoxy was mixed 1:1 with no reducer and shot at about 75* and no more than 40% humidity.
What am I doing wrong or what should I be doing instead?
Please help me!