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That's the way it is when ever one uses cast iron in a precision application. Bridgeport mill bodys are done the same way. Internal stresses in cast iron release as the castings are cooled and heated repeatedly. One can force the issue with repeatedly heating and cooling in manufacturing, and or cyrogenic treatments but that's more expensive.

It's amazing how much tool steel, carborized 4130 and just about any other steel moves over time or when material is removed. Just heating in and oven and cooling in a freezer can release stress. I've often considered doing it in wood to see if the same thing would happen.

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

4 hours is not enough time for full cure on Titebond. Full strength after 24 hours, I believe it says on the container. I don't use it anymore, but I think that's what I remember. I know it only calls for clamping for 45 minutes or something, but it's not the same. Do a lay-up with it, and clamp it between cauls, then take it out in 24 hours. It'll curl like a potato chip. If you wait for 48 hours or more it is more stable. I always let my glue-ups dry for 3 days clamped in the cauls. I think it's the case of it being still wet on the inside, as was previously stated.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I did this Lam neck out of Indian Rosewood and Goncalo Alves, Titebond Original, and a few days of dry and stability time. I have a double action truss rod (home made) in there, and I haven't had an issue with it.

The way I lay it out is to use oversized wood (height, width doesnt matter as much) and glue them all up with bar clamps. Immediately while the glue is still wet, set the block on a flat surface (relatively flat, I use the concrete floor) and press the whole unit aginst the ground to make sure it glues together flat and not banana shaped. After that its a quick trip through the planer then treat it like any other board.

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http://www.sixgunguitars.com

Yeah, there's no reason not to let a neck glue-up not set for a day or so, what's the hurry.

Waddy, like your neck glue up but it bothers me that the lam ends at the bottom of the heel block. Aesthetically, I'd rather have it continue through the heel, so I guess if i were doing that I'd want to build it like a steel-string, with an integral heel and a lam that covered everything. I just can't get comfortable with the partial lamination, if it is used at all.

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Jim Kirby
kirby@udel.edu

All I can say is I've taken cauls apart after 24 hours and there was still wet glue in there. Maybe it was cured wet glue, but it was wet, or damp. Or, maybe like you say the glue was cured but the water remained. In that case, they should not recommend removing clamps in such a short time. Clamps should not be removed until the joint is stable, regardless if whether the glue is "cured" or not. And yes, my cauls are not water removal friendly. They either have tape on them or Melamine and wax.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Hi David, I'm an amateur guitar builder, working on #'s 4 thru 11 currently, but I am a professional woodworker, craftsman, artist, etc, depends who you ask. A fellow named Todd brought up a builder of esteem in Minnesota who has successfully laminated a lot of necks (with titebond). You are also a builder of esteem. As an accomplished creator in various realms myself, I would suggest you call said builder and glean a bit of insight, a professional courtesy of this type is common in the creative fields I enjoy and I would perish in remorse if such courtesy was not extended to you. T

P.S. I attach a photo of a few necks by said builder (titebond bottle included).

Interesting discussion, guys.
Also interesting, that the only creep I've experienced in any neck situation was in the use of epoxy.
That said, I'm willing to take part of the blame for that...perhaps improper mixing, application, whatever.
But the whole experience gave me the creeps (oof) and I'm starting to go to LMI white in neck construction. I think it dries harder, or at least more crystaline, than regular wood glues.

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Maybe I don't know what a "stress jointed" is. At least I didn't think an 1/8" head plate or a few sticks of wood laminated flat together constituted stress joints?

Bingo. Nothing wrong with only a few hours of clamp time on something like a laminated neck, headstock overlay or electric guitar body. A stressed joint would be a bridge. Let those dry a while.

As far as 'wet' glue and letting the moisture out of glued joints don't mistake the amount of moisture in that (hopefully) microscopic layer of glue in the joint you just laid up with those gobs of squeeze out on the outside. That doesn't mean I run a glued up neck right over to the joiner an hour after laying it up, but unless I have a lot of other things to do for the next three days leaving stuff clamped up that long is a waste of time.

If the headplate were 3/4" thick there would be much less stress. But at 1/8", that piece wants to curl and concave to the dry side and it takes a lot of force to hold it down.

With thin pieces like you're referring to, I will wet the clamped/caul side to equalize the stresses.

Thanks Filippo.
Price any better than at LMI?

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com