doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Acraglass question

First; Most belt sandings are to coarse but dust from a orbital sander using 120 or finer paper will work if it is clean. Walnut powder turns black when wetted out by the epoxy. Use a light colored non resinous hardwood powder,like white hickory then add a little medium brown like oak or pecan or apple heart.when you get the color and consistency that you want it will harden to the same appearance .
Second;food color will work for some things but most have Propylene glycol in them and water. adding that to epoxy can give an elastomeric quality to the cured solid and in time cause deterioration. when adding a diluent to epoxy allow the parts to react for a minute before adding the liquid.

Byrddog, that's interesting stuff. You are correct that walnut sandings turn dark with the epoxy addition. My experience when using colored "glues" is to have the glue lighter than the gunstock when applying repairs. The repair always seems to be too dark otherwise.

Some years ago I purchased some epoxy or acraglass stains from Brownells. I don't know if they still have them. Do you know if they worked properly ? I remember a bit of the stain would color quite a bit of epoxy.

I've used very fine pine sawdust or even light walnut sapwood sawdust to color epoxy too. The trick is getting an epoxy color match that will match the walnut when the final finish is applied. You can mix a few different small batches and compare them to a hidden area of the stock like the forearm channel that has a coat of the final finish, before you commit and end up with something that sticks out like a sore thumb. A small piece of walnut which closely matches your stock is good for a trial run too. Good reason to keep a box of those walnut scraps.

They were selling the stain as of last year. I got a few capsules but have not had cause to use it yet.

Rob

I bought, many years ago, from Brownells a box of glass jars with the different pigments in it. A tiny amount on a toothpick is all you need . I mix the pigment in as I stir the two parts of the Acraglass gel together. I have a question, I am using more epoxy with a grey colour, with a small amount of hardener about 20:1, can this marine expoxy be coloured as can Acraglass Gel?
Mike

If you are using dry pigments, the answer is, generally, yes. I have used a lot of marine epoxy over the last couple of years, and the dry pigments are still the most reliable.

Great info guys,

Now I have an additional use for the pieces of oak flooring and old hickory Axe handles I have. I've been using them to make side grain inlets on butt stocks for the plate, usually when some boob has used an end-grain dowel that has eventually split. End grain dowels split and cause the butt plate screws to lose their bite, so often the stock itself becomes cracked, as folks keep tightening the screw. I usually have to drill out the old dowel, square up the hole, glue up the crack with an embedded brass cross piece (usually a brass screw with the head nipped off) inletted and glued across the crack. Then, I'm able to install the side grain inlet and provide a lasting base for the butt plate screw.
Ken

This Marine epoxy that is gray sounds odd to me. 20/1 mix ratio is very unusual. Are you adjusting this yourself or is that what the instructions say to do? It is essential that the resin and hardener be used at the ratio it is designed for. If any portion of the solid has unreacted agents within it the service life will be very short. the unreacted portion will eventually blush out soaking into the wood and softening it.
Dry pigments work well though I find the colors to intense. I have made two small batches of epoxy and filled them with two different colors of wood powder to a dough consistency. swirled the two batches together made the repair. after sanding I got a grain like appearance under the finish.

What is negative about AcraGlass?
I have been using it for 40+ years for all kinds of repairs and have no complaints. I use a disposable 5 cc syringe for an accurate mixture and color with wood dust, black or brown dye when needed, flox powder/fiber for strength if needed.

I have tried the two-batch swirl method a couple of times but without a lot of success. Probably need to practice a little more. Re the intensity of dry pigments, you are correct, and the addition of wood powder does mitigate the color of the pigment. Another approach is to use dry pigment for the color you want, and then adjust the intensity of the mix with tiny amounts of the epoxy pigments sold in the stone trade. Paste pigments are available in small tubes (or large tubs) in a variety of colors from pure white through black, including shades of beige and brown to mimic natural stone. Don't use universal tint colors from the paint store because those will interfere with the epoxy cure and the results are not entirely predictable. I have also tried some solvent-based dyes that are often used for epoxy joints in granite counters, but have not been satisfied with the results in some of the epoxies that I prefer, probably because I am working with such small batches that it is impossible to get consistent mixes. In large batches, the results have been pretty good.