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Not the kind of check I can cash, I have been so happy with my cheap wood, now for the real price. I was sanding the neck and kept working on this scratch, that I just could not get out, only to discover it is a crack. You can see in the picture, the check is causing a small crack to occur across the lamination into the other half of the neck. The neck is POC, 2 piece, using the barrel bolts to attach to the body, I beefed up the tennon on all 3 sides with 1/8" cross grain hardwood to make sure the barrels had some extra meat, so the barrels are now glued in. I cannot get the crack to flex, or open and close, at all when pushing or pulling on the neck, it has never been strung.
So my options as I see them:
Make the heel where the crack is flat and glue some flat grain cherry on as a unique trim feature, then reshape. Easy, an hour or so
Cut the heel off and build up a new one, not easy, new tenon and neck angle, 4-6 hours?
New neck, not easy, maybe 10 hours for me at this point?
Fill with glue, CA or epoxy, finish it and see what happens. Easy until it explodes, then see other options.
I can spline the hole heel and tenon though the barrels are glued in, so I would need to drill them out and remove them, I could run the heel on the table saw and put a spline down the middle of the heel and tenon. The advantage of this would be that it will likely remove wood in the area that any other stress in the area would be relieved then supported by the spline. Pretty easy, an hour or two to make a cutting jig and glue and reshape, then redrill for barrels, 3-4 hours total.
I don't mind it looking a bit funky, no matter what I do it will look repaired, I just want it to work.
Suggestions? Thanks for the help,
Rob

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Fill with white glue & dust (not CA) it will darken the area.
Mix wood dust from the same piece-let dry-then get a fine line permanent marker the same color as the late growth lines.
Carefully make the lines from above & below the crack touch with the marker.
You can even use a pencil of the same color.
Wood is wood !
Poop happens !
Learning to work with woods inherent problems is just part of the
guitar & all other woodworkers learning curve.
Or prob. the crack with a feeler guage to find it's depth.
If it's only 1-2mm deep you can saftly sand it out.

Mike

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Mike Collins

Robert : Something for you to consider. If the crack will close under clamping pressure,drill a 5/16 hole in the heel cap area that will go past the crack but not break through into the truss rod channel.Fit a dowel to the hole so that it enters easy but with no slack. Cut the dowel so that it is about 1/8 " longer then the hole.Put glue in the hole so that it comes up past the crack ,put some glue on the dowel. Insert the dowel and use your vise to push the dowel into the hole. Hydraulic pressure will push the glue out through the crack if it crosses the hole. Clamp the heel to close the crack.You may have to have a caul to go around the dowel.Do this before doing any gluing and maybe try a practice run on scrap to get a feel for the force required to push the dowel home. Good luck.
Tom

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A person who has never made a mistake has never made anything!!!

Thanks Mike and Tom, good suggestions. Probing with a feeler gauge will certainly help with a decision, the heel is already as thin as I want to go, so sanding out is not really an option, but some glue and a pencil, that is my favorite option.

I did think of the dowel trick last night, the big advantage is that I can make it all hide in the end by replacing the heel cap, the downside is that quality of glue surface is somewhat lacking, between the heel and the dowel, much of the glue surface is end grain, though I think in the end it would be a viable fix, I can also see if it is too tight, I can make matters worse.

When I was a young door maker, I doweled some doors a bit tight, and saw how the hydraulic pressure works, I thought clamp pressure would get the door together, bent the clamp handles and then the wood exploded. After that I zipped the dowels on the table saw to make a spline for glue to move around.

Yeah, this is the poop that happens, overall, this build for a #1 has been really smooth, and a few hours to fix this is only a small hump, I really don't want to make a new neck or cut the heel off.
Other suggestions?
Thanks,
Rob

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Any chance that the neck wood wasn't dry when you glued the cross grain enforcement on the tenon? Or is the humidity a lot lower now than when you glued the reinforcement?

Looks to me like a shrinkage crack. If it was a defect in the wood, it wouldn't continue on the other half of the neck unless those are bookmatched pieces.

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Kent,
Good question, although I am not in a climate controlled environment, the weather was good and consistent when the tenon was reinforced, but the part that does concern me is that I wet the wood to raise the grain during finish sanding, perhaps too much water landed on the very thirsty end grain there. Could that cause a crack of this sort? It certainly happened recently as the line in the other stick shows. This is not well seasoned wood either, I was guessing the lack of seasoning being the most likely cause, but certainly suspect the tenon caps and the wetting the grain.
Rob

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Wetting the wood for sanding wouldn't be a problem. The problem would be the heel drying and trying to shrink while the cross-grain reinforcement wants to stay the same length. Since the heel isn't free to shrink, it splits.

If this is the case, then the fix may be different. If the wood was not completely dry to begin with, then the suggested fixes are the way to go. If it's due to very low humidity, I would humidify before messing with the crack. It may close completely on its own.

Good luck.

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I am doubting it was a drop in humidity, humidity has been steady.

So the repair that I am leaning towards is the dowel approach, but that still leaves a couple of options. One large dowel in the middle, removes some of the glue joint, or two little ones on each side of the glue joint. Then come the materials and glue, I have some thin CF archery arrows, I can do 2 small holes and epoxy, therefore not dealing with adding moisture from wood glue and the subsequent expansion contraction. Am I right to be suspicious of wood and wood glue here? The wood glue will be mostly interacting with end grain, so not at its best strength. The downside to CF is that if it fails, I think I am quickly moving to cut off the heel as my only repair, the big spline idea is out.
Rob

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