Repairing cracks -some comments
Good morning Joel!
Claven2 has described elsewhere the classic method used by antique restorers - a mix of shellac and wood dust from the matching type of wood. This can only fill - it does not have any worthwhile strength in tension. I don't think it would be suitable for long cracks in a piece that is subject to flexing, and the RB fore-end is pretty whippy. He has also described the alternative we have with modern materials - to make the mix with epoxy resins, and this is then a repair that has considerable strength, provided that it binds to the wood.
The trouble with the cracks we see here is that they are very fine - and full of crumbs. At least, it was on the dining table I refinished recently - crumbs, old candle wax etc. etc. I had to scrape out the cracks as best I could, using a hooked tool, before even attempting a repair. I have no idea what the technical term is, but it looks rather like a very fine C-spanner (the tools used for tightening the pedal hubs on bicycles) with a wooden handle - in effect, a super-fine lock chisel.
Speaking as an old experienced packrat, you can probably find a scrap of steel or brass plate that you can file or grind into a suitable shape. Something even better, if you can find it, is a dental pick, as used by dentists to remove chalky deposits from your teeth.
Claven2 will give you the full story for the epoxy method, but I would like to note that I am on the track of something that is possibly better for thin cracks - melamine formaldehyde (melamine resin).
If that rings a bell, it is because it is indeed the substance that was used in the Great Chinese Milk Scandal, but it has a serious use in archaeology - for conserving ancient and especially waterlogged wood, such as wooden ships. I talked with one of the staff in the Mary Rose exhibition at Portsmouth about this - it turned out he was a muzzle-loading shooter, and we had a great conversation.
It is a watery (in fact, water soluble) resin that can be squirted into woodworm holes to stabilize the wood and stop the surface breaking out. And, of course, it will run into the finest crack. That would make it a good choice for crack repair, from the mechanical point of view.
On the other hand, it might penetrate too well, and cause problems at the surface. A cabinet maker and restorer who has professional experience with this material is going to provide me with a sample quantity and some advice on how to use it.
For now, I leave you with Claven2 to deal with the cracks in the tried and tested manner.
(Claven2 - have you any experience with melamine resin?)
"Hey Patrick,
How about we proceed with finishing the buttstock"
- Only after the cracks have been dealt with!
:wave: