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Darn it - I got a little too zealous with a mallet plugging an oversized endpin hole and cracked the tail block. I leached diluted (titebond) glue into the crack, and then put a 1/4" Mahogany plate inside over the tail block (grain going top to bottom) to support it. Does this seem like a reasonable approach? Alternatively, I was thinking take the back off and replace the tail block, or try and get the old block out and a new one in without opening the box . . . but that seems daunting. Keeping in mind I am trying not to ruin the sunburst finish in the process. Anything thoughts, other than easy with the mallet?

Regards,
GS

Sorry to hear that George. This is why I went to 7/16" baltic birch ply for the end block...I had dropped a mandolin on the endpin once. That was it. Granted, that's a pretty extreme situation and the resulting instrument was not pretty with 7-8 cracks on top and bottom.
It does solve the problem of grain direction though. As far as your instrument goes, if it is a customer build, I would get the block out. If it is for you and you feel you have done as good of a job as you can, I would leave it. I suppose it has cracked ribs...photos would help.
It is a lesson learned, and would seem like you could tone down the force a bit!

Yes it is one of mine (not customer). This qualifies as an after 10PM error, I know better, and wanted to get just a few more things done before bed. I'll string it up and if it doesn't separate . . . leave it, but if it starts to separate take it out. I am thinking with some heat and light steam I may be able to get it out without completely opening the box. Maybe take the binding off the tail end and great hot knife between the top / block / and bottom. Anyone tried this? I like the idea of Baltic ply going forward. Thanks. GS

Your repair should be solid - no worries. . .

_________________
Cheers,

Frank Ford

FRETS.COM
HomeShopTech
FRETS.NET

Frank - I took a look over at FRETS.COM, today and this is almost exactly what I did http://www.frets.com/FretsPages/Luthier ... crack.html

Even using the spool clamp - I didn't think to push the bolt in from the outside (easier) I had my son look through the tail block hole and let me know when I had the bolt lined up, but pretty much the same.

I must have seen it there before and forgot about it. Thanks.

I think Bond tite and clamping it should have worked also.

Here is a trick I learned gluing cracked headstocks that would have worked here too.

You can thin your glue, but you don’t have to. If you can spread the crack without damage, do it.

Squeeze lots of glue in the crack and around the outside.

Then take a compressor with a high velocity nozzle and blow the glue down in the crack. Forget gravity or capillary action, force that stuff down there!

Clamp and wipe off the squeezed out glue.

It works like a charm!

I’m sure someone here has already shared this, but just in case...

And I have learned a lot from Frank Ford’s website. It’s like an online guitar repair bible!


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