should'a used hide glue

[austin]

During clamping I had a neck drift out of alignment from the bottom center mark about 3mm.
I used titebond and just don't know how to get it apart and redo the joint.

Any suggestions for how to take it apart?

thanks,
austin

[sunburst]

I don't know what kind of joint you have, a dovetail or mortise and tennon would be self aligning. Heat will get it loose. Steam will help too, but isn't really nesessary with titebond.

If the joint you're using can allow things to slip, you'll have to have a way to controll that no matter what glue you use.

[austin]

It was a dovetail and I must have misplaced my shim or something because it was tight and well aligned when I test clamped it.

I suppose it would be sort of gauche to use the fingerboard to recover that little bit of off centeredness??

[Big Joe]

Steam works well in the neck joint area. It could be hard to get enough heat in there otherwise to loosen the glue.

[sunburst]

Yep, steam will do it.
You could adjust other things to recover some alignment if there is still enough wood on the neck, but it wont be too hard to get that neck out and try again. Besides, you'll end up with a better job and there is more to be learned by taking it apart, figuring out what went wrong, cleaning the glue off, and trying again.
Don't think you're the only person that ever had something like this happen, btw. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif

[Chris Baird]

Not that perfection isn't what you should shoot for but some loars have necks that are off by 3mm from the center. I'm regularly off buy 1 mm. I can easily glue the fretboard on in such a way as to negate the slight dovetail discrepency. Bringing the centerline over 1 mm only takes a fretboard shift of less than .010" at the end. Bringing it 3 mm might be pushing it though.

[austin]

Well, thanks for the input guys, I guess I'll try to pull 'er off tonight.
My only worry with the steam is that I used hide glue on my sides/blocks and am afraid that will loosen faster than the titebond....

and yes, I would like it to be as close to perfect as possible even though I do have room to shape the neck to fit a realigned fingerboard.

[Chris Baird]

One of the biggest challenges trying to make money building mandolins is to make them fast enough to clear a reasonable profit. One of the biggest consistant improvements in speed for me has been in further understanding the tolerances of the instrument and the most effiecient way to obtain those tolerances. It would take me probably another hour or two to fit a dovetail such that it was dead on with the proposed "center" of the bottom of the mandolin. I've found that allowing myself a 1 mm tolerance saves me hours of fitting and can later be perfected with a fretboard alignment which takes no extra time at all. This is not to say that within the dovetail there is any tolerance as I wouldn't and have never allowed a need for a shim but there are other tolerances and if one knows where to be "perfect" and where to be "close" you will save much time and wasted effort. If you can adjust the fretboard enough to be lined up perfectly with the bottom center then in my opinion that is perfect because you will end up shaping the neck accordingly there by removing the "imperfection".

[austin]

Well, however educational it might have been, it was a real pain getting the neck off the body. I do think I could have removed it easier if I had used hide glue for the joint instead of titebond, (I use hide glue for everything in the body and for gluing on the fingerboard) but I really didn't think I would have to remove it. Doh!

Anyway, thanks for the advice, everything fits nicely and is well aligned now and I can move on again...

Chris, I do think that had it been less than 3mm I would have just used the fingerboard approach, but I measured and it would have been off just a little more than I was comfortable with. And hey, what's another three hours .... I am only selling it for enough to pay for the pleasure of building another!!

-austin

[Jim Hilburn]

I've found that if you use a tapered dovetail and you have a tight physical fit, titebond can set permenantly before you can get the joint fully dropped into place, leaving the top out of the joint by 1/32" or so. But if you pre-heat the joint,hot hide glue is almost like a lubricant and you'll have no trouble getting the neck fully seated.

[Luthier Vandross]

I have pulled Tightbond joints apart 2 days later, just by using a blow dryer, and shielding the finish around that area with cloth, or whatever works.

While the glue is still 'fat', it heats out easily... and if you are real careful, you just help cure the neck block.. ;)


M