Anyway, my LT-40 took a 30 foot nosedive into a field.

I have to reglue the firewall, which was epoxied in to begin with. Should I remove the old glue and wood fragments or make use of them?

Cleaning of the shards and old glue is probably going to leave gaps.

thx

Hard to say without seeing it, but you can usually fit the broken piece back in while lining it up with the broken bits that are still attached. Use 30 minute epoxy and clamp the fuse sides so the firewall is held tight while the epoxy cures. (24 hours at least.)

Good luck,
Dennis-

Keep everything that was there. That way when you put it back together there is a perfect fit.

Just use a bunch of 30 minute epoxy and don't hesite to use a lot of it...

Then add some tri-stock to the rear AND front of it. Usually it's easy to do right after you've put the firewall back into place. That way there is only one job and it's all all wet glue so everything fits.

Some pins through the fuselage sides and into the firewall can really help as well. Use toothpicks or little pieces of plywood. Just drill little holes and stick them in with some glue.

I was mostly worried about the epoxy bonding to old epoxy, the firewall came out in one piece with just a few thin shards of wood.

If you leave the epoxy smooth new glue will have a bad time sticking. Use a knife to add some scratches to the parts being glued. No need if the wood is bare however the glue is what you need to rough up. Drilling small holes for the glue will penetrate will also help with strength. Should be an easy fix.

EXCAP232

Yes, what excap said.