Alternate way to cure fiberglass resin ?

[Ed_K]

To get ready for the convertable top installation, I filled the old screw and nail holes in the four wood pieces with epoxy, then sanded. Lastly I painted the wood pieces with fiberglass to seal out moisture. The fiberglass cured hard in the container that I mixed it in, but it is still sticky on the wood pieces ? I guess since it was painted on in a thin coat, there is not enough material present on the wood surface to heat up and cure ? If I put the pieces in front of an electric space heater, will that create enough heat to cure the fiberglass coating that I painted on the wood ? Or will I be cleaning the wood pieces tommorrow with acetone to remove all of the uncured fiberglass resin ?
I guess I should have used something else to seal the wood other than fiberglass resin.

 

[Dave Russell]

Try it and see. You don't have anything to lose. Either it hardens or it doesn't. A heat gun or hair dryer might be better. Heat should accelerate the cure noticeably.
D

 

[Ed_K]

Thanks Dave. I was hoping that external heat would cure it. I have not had very much experience with fiberglass and didn't know for certain.

 

[Dave Russell]

Heat certainly works on other types of epoxy. Should work on FG resin also. I wouldn't get it TOO hot. It should even cure without heat. Just takes more time. If it doesn't cure, acetone will remove it. Let us know how it works.
D

 

[Keoke]

Should have used Epoxy ED . Glass resin does not like being applied over epoxy. The other way around is ok. If it does not set I would clean thoroughly with acetone and smear the wood with Five min epoxy using a finger really rub it in and sand after it cures. Should you need more working time get 15 min epoxy.---Fwiw---Keoke

If you have to go this route be sure and over catalyze the epoxy slightly.

 

[GregW]

I have found that thinly applied layers of epoxy (or polyester) need more hardener. I did a steering wheel that after three weeks was still tacky (not to look at).

 

[Keoke]

[ QUOTE ]
I have found that thinly applied layers of epoxy (or polyester) need more hardener. I did a steering wheel that after three weeks was still tacky (not to look at).

[/ QUOTE ]

Yeah, and that was the one he was gonna put up on E-bay and sell to me.--Keoke- /ubbthreads/images/graemlins/yesnod.gif- /ubbthreads/images/graemlins/grin.gif

 

[zblu]

cheap way of getting the f/g resin off your hands is to get some dry washing detergent+smidge of water and scrub your hands together, just washes off, you'll feel some heat during this, cheaper and better than acetone, probably work on the wood too!

 

[bighly]

Give it a very light coat of hardner.

 

[MotorHead67]

I agree bighly.
It's common to seal boat seats made of wood with a coat of resin to seal out moisture. I did it on my boat. Then upholstered the seats.
Also, there might not have been enough catalist in the mix.
The mixed resin in the container will build more heat and harden faster even if there wasn't enough catalist to harden on the wood.

 

[zblu]

about a 50:1 mix

 

[Ed_K]

I certainly learned a couple of valuable lessons today.
1.. Don't put on a thin layer of fiberglass unless you have a few weeks to let it cure. I tried using a hairdryer and it seemed to work a little, so if a little heat was good, obviously more heat would be better... and
2.. The wife was gone to the store so I put some aluminum foil over the rack in the oven and baked them at 350 for a while. Where was my common sense ? It didn't take very long before my house started stinking like this factory I used to make service calls at that made fiberglass bathtubs. After opening my windows and putting a fan in one to speed up the removal of the " evidence ", I was back in the garage cleaning off the uncured resin. After I got them cleaned up again, I used a regular polyurathane wood sealer /finish.
/ubbthreads/images/graemlins/crazy.gif

 

[Keoke]

/ubbthreads/images/graemlins/lol.gif--- /ubbthreads/images/graemlins/lol.gif---------------Keoke- /ubbthreads/images/graemlins/yesnod.gif


More on the serious side ED. The fumes from the heated Fibre glass can be very toxic.- /ubbthreads/images/graemlins/yesnod.gif

 

[dklawson]

Another thing to be careful of when heating polyester resins is not to use so much heat that the heating element glows. That red glow of the element is a good ignition source for flammable vapors. Keep the heat low (like 200 degrees low) when baking parts. Preheat the oven, then quickly put the part in there. FWIW, when I have done this with any part (for paint curing or glue curing), I turn on the hood near the oven, close the kitchen doors, and I burn scented candles from the moment the part goes in the oven.

If you want to start over, use acetone or lacquer thinner to wash out the uncured polyester material, then start again with epoxy.

 

[Ed_K]

Doug,
I am happy to report that I am done with these repairs and I just got back from delivering them to the shop that will install my top. Now If I can only pick up my car at the body shop. Got a call this morning saying he was done painting but the paint didn't match the rest of the car and he would be respraying the repaired area again today with computer matched paint. Perhaps I can pick it up this Thursday ? I need to learn to ALWAYS add at least 50 % to any time or cost estimate related to restoring vintage LBCs, no matter how " simple " the task is said to be !
/ubbthreads/images/graemlins/crazyeyes.gif