I need to add some material in a couple of places on a McMillan fiberglass stock and looking for a material that will be stronger and more moisture resistant than Bondo but easier to work than a metal bearing epoxy like Devcon.
I'll be using the material built to 1/2" or better in thickness so structural integrity is important.

Anyone here have first hand experience with something that might fit the bill?

Have you tried Locktite's epoxy putty? Comes in a clear plastic tube and looks like a roll of candy.

I first used it when I purchased a stock from HS Precision and they included some with the purchase. I've since used it for bedding in a heavy recoiling rifle and it seems to hold up fairly well.

It definitely beats Bondo.

marine tex grey ..

i haven't tried the epoxy bondos

Have you tried Fiberglass and resin??

It would be really nice if you could tell us what you are planning to do.

What do you mean by "easier to work": easier to sand/shape once hardened, easier to form while setting-up, or something that keeps its shape and holds in place while hardening?

If you just want to fill an safety cut-out the epoxy putty that comes in a roll would probably be fine.

If you want to make it easier to sand microballons from TAP plastic would be great because and they would have the added benefit of increasing the volume of your epoxy and making it lighter.

You could also add something like talc to make the epoxy more sandable and less likely to sag.

quote:

Like Bondo, but better?

Bondo is basically fiberglass resin(aka polyester resin) with a filler added.

So an epoxy with a filler added is basically "like Bondo, but better".

I believe there may be epoxy based body fillers on the market.

Google System 3 Epoxy. They make an epoxy fairing compound for boats that's much, much better than Bondo. Easy to sand too.

I have had great luck with this apoxy clay

It is very easy to work with. Fill in your problem areas. You can smooth it out and feather it in with your finger dipped in water. Sands very easy with drywall sanding screen. Sticks to anything and rakes all types of paints and is solvent proof once dry. Cleans up with water while still wet. Only problem is it can a be a little hard to get thin. But it sands so easy I have had no trouble putting it on thick and sanding it down to the level I need. Just sand within the first 24 hours after it sets up.

I would use the thicker fiberglass reinforce "Bondo Glass".

After it fully cures for about a week, it is about as strong and anything inside a factory Mc Millan stock.

Jason
In the auto body world which I have been out of the loop for quite some time we use to be able to get a product called E glass. And there was a whole shelf dedicated to these different body fillers. Yes there are fillers out there epoxy based fillers right along with the polyester risen fillers we have known for years.

I will say one thing Bondo is brittle and if used in a thin section it may crack or snap. If you are trying to fade some extra material in to an area that may become to thin Grind out the base material so you can build up a thicker section of filler and not have your filler fade out to a feather edge on top of the base.
Kinda hard to explain in words.

I'm inclined to use the marine-tex if it doesn't tend to run while setting up. I'll be adding a thumbrest to a handgun stock and bulking out the very thin sides along the bbl channel to accept a larger dia barrel.

Thanks for the replies.

Accra-glass and micro ballons for the barrel channel .

First tape off the clearance required and then mix to be fairly stiff.

You can wet the barrel chanel with accra-glass first and lay in a few strips of fiberglass cloth.
Glenn

I ordered some Marine-tex grey which should work fine for what I need to do. Thanks for the replies.

If the Marine-tex is too thin, international pistol and position shooters use a clay type epoxy to fine tune their grips. I don't know of a source off hand, but bet you could find one on the Pilkguns sponsored forum called TargetTalk.

Don't know if it is the same but the link I posted sounds like what your talking about.