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Sorry to bother you with a ukulele question, but here goes: I broke a rule and was doing glue-ups while tired. On a 12 fret concert sized uke, I glued the heel block on perpendicular (90 degrees) to the neck grain instead of stacked as I had intended. This uke is for me, so I don't really care about the looks and wasn't going to do anything about it, but then got to wondering if there will be a structural problem with this. I intend to do it as a flush, bolt - on neck. I got to thinking that this might be a really weak joint with end-grain glued to the neck. Even though the string tension is minimal on these instruments, do you think this is going to be a problem? If so, how would you remove it without risking damage to the neck (those scarf joints always take me a long time to get just right and I don't want to ruin the neck). Anyway, I'm sure glad this happened on a uke and not my steel string!

Thanks for the advise! Beth

Beth,
It will be fine as long as you maintain humidify control.
If it will have large swings for dry to wet, it could be an issue.
The big issue is not bond strength, but expansion and contraction with changes in humidity. Wood swells and contracts due to changes in moisture content more across the grain than with the grain. That difference is what can cause problems.

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Beth:
Exactly what steve said. A set of ukulele strings pulls around forty pounds force total, there is no way that there is a structural problem. Your heel should have some interesting grain paterns.

good luck.

Bob
A mistake is getting something that you don't want. A surprise is getting something that you didn't know you wanted until you had it.
Rosanne Barre

Beth,

If I understand you correctly, you have the end grain of the heel block glued to the bottom side of the main neck section. If this is the case, a glue joint on end grain is never a great thing structurally. The thing that Steve is saying about the cross section of a piece of wood moving more than the length of the wood is especially important. In my experience, wood will grow with increasing humidity and also will shrink with increasing temperatures. IMHO this type of joint will be compromised by any change. If it were mine, I would cut it as close to the back of the neck as possible, making sure the saw cut was in the heel block. Then clean up the back of the neck and re-glue it. Hopefully you have enough length on the heel block to re-use it. OF course a band saw blade will make a thinner kerf if you are really pressed for length.

You will also feel better about correcting your mistake rather than letting it slide. Of all the mistakes I've made in building, the only ones that really bothered me were the ones that I let slide. Some how they always come back to haunt you. Don't ask how I know.

Happy building,

Mark

_________________
A world without music would Bb.

Thanks guys! I do keep my music room very tightly controlled for temp and especially humidity, but I want to be able to take it out in the world (my world is the desert southwest), so it sounds like I should bite the bullet and take it off.....that's what I'm gonna do.
I appreciate the information....thanks for taking the time! Beth