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I have this crotch cherry blank with drying checks. Are there any negatives to filling with WestSystem and sawdust before shaping? after shaping?
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Pretty piece Jeff. What advantage are you thinking you'll gain by filling prior to shaping? Will it help remediate chipping?

Yes, just to stabilize things, help prevent blowouts, I'm not clear where the stress is in a piece of wood like this.

While most of this figure will be in the widest part of the butt, if I bandsaw close to template, it's gonna have a lot less support around the wrist.

I was thinking of bandsawing close to template and letting it sit another year.

How old is the blank? If it is completely cured, it shouldn't really make any difference if you let it set before or after you have it cut. It shouldn't move after it is cut if properly dry.

If it is still wet, cutting it before it is ready will release some of the stresses and it will undoubtedly move, regardless of the stress cracks. If you must cut it before it is totally cured, cut it when the temp is low and humidity is high, then place it in a cool, dry place to finish curing- like a crawlspace under a house.

Great looking piece, but inherently unstable in any case regardless of how you treat it or cut it. Sometimes you just take your chances and see where it ends up...

Bob

West System does not dry clear and develops an opaque look when exposed to UV. It is a great laminating epoxy and sealer but cosmetically there are better choices

Several manufacturers, System Three comes to mind, offer clear, low viscosity epoxies which are used as a base coat under varnish in harsh environments. I use it as a base/primer coat on teak rails, hatches, etc. on my sailboat and it remains clear indefinitely in the sun.

I have seen West System turn pretty wood a foggy, baby-[bleep] yellow in similar circumstances.

I work with a lot of cherry in my shop, and defects like that are pretty common. I use West System to fill by first thickening with colloidal silica, then mixing in a tiny amount of sanding dust taken from adjacent to the defect. Caution: a little dust goes a long way, and be sure to thicken before adding dust or it'll immediately get way too dark. Done properly, no one will notice it, especially if it's located in a highly figured spot.

I refuse to scrap beautifully grained cherry because of minor defects. It also seems that almost every piece of cherry has a defect or two- it's the nature of that beast.

I can only add to heat the wood up so that the epoxy flows into the crack as much as possible. I wouldn't hesitate to use West of Sys III with some sawdust to fill the cracks. Epoxy sands fairly well so it shouldn't be a problem filling before working the stock. The only thing that can bite you when gluing a crack before working the wood is if the repair is harder than the surrounding wood and causes a high spot. I wouldn't worry about the UV degradation as that's going to be a fairly small repair and should be unoticeable.

With the disclaimer that I have not exposed epoxy coating to prolonged sunlight, I have had excellent results using West Systems 105 base resin with 207 hardener. I believe 207 is intended for laminating things like fiberglass surfaces, but it mixes into a clear, low viscosity mix that goes on nicely and, with heat, thins out and penetrates very well. It also hardens in thin layers, something not all epoxies do well.

Since you appear to have a lot of experience with epoxies, I'd be interested in learning the specifics of those you have had good results with, and prefer, especially for gun stocks.

Thanks for posting.

Paul

We regularly used WS 207 as a sealer coat when doing brightwork (varnished exterior wood trim) in the yacht carpentry shop. It has zero UV protection, so a quality varnish with a good UV rating is mandatory over top of it.

Heck, I have even used West System 205 and 206 thickened with colloidal silica to "glass bed" rifle stocks. Years later, still no problems and none expected.

Thanks guys, there's a lot of good information here, I appreciate the help. This blank is 15 years dry..so it's probably stopped moving, even after I cut into template sizes.

I regularly use 205 hardener for laminating super-hard woods like Ipe and Jatoba, but they are for interior work. I will get some 207 and try it heated.

How are you heating it??

I never heated it. It's viscosity is low enough that it spreads like spar varnish. We never heated it when using it as a sealer coat on boat brightwork, and never had a finish lift as a result. We had company reps advise us to never thin epoxy with solvents and that heating the surface whether to promote absorption or to speed curing was a surefire way to lessen the integrity of the epoxy- to one degree or another. The only joints I ever had fail that were done with epoxy were a couple of times I was in a blazing hurry and used heat lamps to speed the process. Lesson learned- think ahead.

205 and 206 were used for many exterior joinery/lamination applications too, to the tune of a couple 50 gallon drums a year. The key was good UV protection afterward via quality varnish or paint. UV light will degrade epoxy quicker than anything, short of heat and solvents. This from a lot of years in the wooden boat building game.

Adding saw dust to the epoxy will always come out darker than the original saw dust color, it will look permanently wet. Use mostly the silica for thickener if needed and just a small amount of saw dust. An alternative is just silica and dye powder made for the purpose. The saw dust does aide in improving sanding properties.

Probably not a concern, if it is too dark just leave it in the sun till it matches.

Try a a few test mixes as the color can change when drying. But those checks are so small it shouldn't be a problem. I do agree on doing this before profiling as no telling what is underneath so better prevent any chipping than to find out later.

And post pictures, that is an outstanding piece of Cherry.

Personally, black epoxy looks great when used to fill such small cracks. The notion that the stock will see enough UV to cause yellowing or that one would notice such small spots is entertaining. As gnoahhh pointed out a finish on top will prevent the "problem."

Using crotch wood up into the wrist is a mistake however, unless serious precautions are taken... boring into the end grain and epoxying in a piece of solid, high quality wood to guarantee the strength of the wrist is a really good idea.

Cutting it will allow some wood movement, regardless the age or drying conditions, and letting it sit for a while between steps is not a bad idea.

Setting epoxied sawdust in epoxy and expecting to change the color with the sun is another exercise in futility.

A client brought me a stack of American chestnut, cut many many years ago and stacked in a farmhouse attic in Ohio (talk about extremes in heat and humidity!). My task was to take that pile of twisted wood and build an heirloom dining table. If it had been anything other than some beautifully grained chestnut, with sentimental value, I would have sent him packing. As it was I planed the stuff very thin and epoxied it onto a Baltic birch plywood substrate and applied heavy battens to the underside in order to tame that crazy wood (it worked). The crotch figure that was present in several of the planks exhibited seasoning cracks as shown in the opening post. After construction and before finishing, I filled those cracks with un-thickened epoxy, sanded flush, and varnished overall. Those cracks now look dark with a translucent quality, and actually compliment the effects of the crotch figure to my eye (and the eye of the customer, thank god). A couple planks were obviously limb wood and really bent and twisted- they provided the material for edge banding the table top.

My point is, if a piece of wood has stunning grain but with some flaws, there are usually ways to make it work.

Black looks best to me with Mequite should work on Cherry. The Cherry wood gets darker in sun not the epoxy.