Help Stabilizing Crack in Walnut Stock Blank

[jonboyb]

Been holding on to this piece of highly figured walnut "groin" for a long time and it was dried before I got it. Been stored in my gun room for years. A while back I saw the beginning of a small crack and decided to go ahead and rough out the stock (just a back stock gun for an underhammer action) and the crack does extend deeper than I had hoped. I think it will likely disappear as I form the stock but want to attack it now. I would be heartbroken to not be able to use this piece...the color and figure are unbelievable in person.

Looking for options on arresting the crack now before I proceed any further. Don't want to take any chances. It's a little hard to see in second picture but directly below crack location in first photo. Thanks.

 

[galamb]

That's a tough one. Normally I would suggest unthickened marine epoxy.

BUT, epoxy does soak into the surrounding wood and after you get it down to shape you might find you have a spot that won't take stain/finish and stick out worse than a sore thumb unless you are "fairly certain" that you will remove enough wood during shaping to completely get past the current crack.

Otherwise I would leave it be or get some of that stock taken down sooner rather than later.

 

[BrownBear]

Am I interpreting the photos correctly in seeing that the stock goes all the way THROUGH the blank and is spreading across the length of the blank?

Egad. If that's the case, I'm guessing if it continues to spread you're looking at the blank eventually parting at that point.

If so, stabilizing it might be kinda like getting down on your hands and knees to chase coyotes.

 

[Lock Nut]

While I'm no expert on the subject, I think I would try to mix up some acraglas (the thin stuff) or some thinned clear epoxy and inject the glue in the crack with a syringe.
Nice piece of wood. Hope it works out for ya.
If it doesn't work out, You got some nice pistol blanks :wink:

 

[jonboyb]

Am I interpreting the photos correctly in seeing that the stock goes all the way THROUGH the blank and is spreading across the length of the blank?

No, blank is about 2.5" thick and the crack extends approximately 1/3 down the face. The crack kinda follows a grain/mineral stain and what you're seeing. There's ALOT of wood to remove there so I'm fairly confident it will disappear. I cut a sliver off that face about 1/4" thick across the crack and couldn't break at the crack with considerable force. Including a picture of the thin slice "wetted" and honestly can't find the crack in my own picture...LOL. I think it is around the upper right.

 

[BrownBear]

That's good news! I just couldn't make "sense" of the two photos. My bad and your good! :hatsoff:

 

[jonboyb]

Just roughed out my geometry along the bottom where the stock will end up finished and I'm even more confident that it should disappear, but likely going to inject some marine epoxy as a safety precaution. Don't pay any attention to the sharpie mark on the first photo....that was a drawn-on modern stock design from the shop I picked it up from and has nothing to do with my build.

 

[Woodyrock]

An epoxy that will truly penetrate the smallest crack is HXTAL. You will cough, and choke at the price, ($50.00 per 3 ounce) but it will penetrate like nothing else will. You only need a wee bit, like a couple of drops, and put it on warm wood...not hot. If you know anybody working high end lapidary (gem stone) materials you might get them to put a couple of drops on for you. You could try a local Gem and Mineral club.
Woody

 

[Rifleman1776]

Wood turners who work with figured stuff regularly put some thin CA into those cracks. But, finishing to hide is another matter. And bowls do not get the stresses a stock does. Personally, that looks like a discard hunk of wood to me.

 

[Birddog6]

I think you will have issues with that blank period. IMHO. :idunno: It Is... drop dead gorgeous, no doubt about it. However, I don't see a place to put a gunstock on it that would not have grain runout everywhere. Either the wrist & butt will have full runout, or the entire forestock will have full runout & possibly both. Definately don't want the wrist to have runout, so you will have to lay it thus the forestock will have runout.

Maybe I am just seeing it wrong. :idunno:

It would make a great table top tho ! And even that would require good support all around the edge under the top to prevent it from warping & cracking.

Keith Lisle

 

[jonboyb]

There is no forearm.....just a butt stock similar to a shotgun style. For an underhammer design. Very straight compared to a traditional muzzleloader drop. There will be grain runout at the tip/wrist but that end is encapsulated if you will in a steel band at the rear of the underhammer action. My apologies.....very hard to put in words....lol. I was saving this piece specifically for an underhammer setup since I knew the grain would be disasterous at the wrist.

I'm going to shape this area tonight and get it to a rough final profile to see what I'm dealing with. Anyone recommend a sealer I could use as I shape the stock to seal various areas as I progress? Something that stays on the surface and sand away once its time for final smoothing and finishing? May just stabilize the entire piece based on what I find during this initial shaping.

 

[ohio ramrod]

I use CA glues a lot on wooden furniture for cracks. It is strong but brittle. So I would not recommend it for a stock. :idunno:

 

[jonboyb]

Spent about 5 minutes with a rasp and the crack is quickly disappearing. This piece is so dang hard 5 minutes with a rasp doesn't go far :haha: Hopefully have time to finish the area this evening....but thinking real hard about sealing as I go in case it was a drying induced crack.

 

[Birddog6]

I would seal it with Permalyn.

Keith Lisle

 

[excess650]

I have to agree. As attractive as that piece is, I CANNOT see a suitable buttstock layout. The grain flow is all wrong....

 

[rich pierce]

Grain flow is much less of a problem for a half stocked underhammer with a tube like action. Use it and love it. If you see a major problem then drill from under the buttplate forward toward the action, slather the hole with epoxy, and insert a threaded rod that will just fit. If you use a hardwood dowel it could contract or expand at a different rate than the walnut and make things worse (or not).

I would not use epoxy or anything synthetic, but would use a wood patch glued in, to fix a surface crack on wood that figured. In a pinch a small crack can be filled with cutlers resin, which I make from cooked and strained pine pitch, ground charcoal from the fire, and a little beeswax to give it a little more plasticity. That is a period technique and will show as a lustrous black line under the finish.

 

[Birddog6]

Oh I can tell you it IS a crack induced from drying & because how the slab was cut.

Take some rubbing alcohol on a rag very wet & rub the area you filed & sanded. Wet it good then let it dry & watch it & if the crack is still there, you will see it a dark line as the alcohol evaporates.

I would seal the crack only with thin Super Glue so it can penetrate into the crack. Then seal the entire piece with a fresh can of Permalyn.

I don't build underhammers so cannot tell you about the wood grain necessary for it. But am very suspicious of what you have, as the plank appears to be cut all cross grained. Beautiful but may require additional support in most applications.

Keith Lisle