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After stringing up for the first time and playing a bit I noticed that the inboard bone strip has pulled up along its length from string force.



The tie-block inlay had been glued with LMI white. Any suggestions on the best fix? Thanks.

Joe

I would use HHG for this job, but LMI white should work too. It seems maybe more like a design problem. Maybe your bone inlays are too deep. The inlays are there to protect the corners. Are the holes drilled through bone too? The problem really seems to be that the strings are pulling up the bone.

Hope that helps!
Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

Thanks Francis. On inspection, it appears that pretty much no glue adhered to the surface of the bone while it adhered well to the rosewood. Here’s another picture that answers your question about the position of the holes.



Joe

What I see on this photo confirm my theory. I'd suggest you reglue it well, and it should stay in place, but I'd also suggest you, for the next time, to review the design. The string should push the bone inlay instead of pulling on it, like it's the case here. Just make sure the holes are below the bone.

Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

Ok, I'll re-fit and re-glue, and let you know how it turns out. Thanks for the help.

Joe

If you have some, try hot hide glue, or fish glue.

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Francis Richer, Montréal
Les Guitares F&M Guitars

I use CA for that. As was mentioned the problem is that your strings are contacting the bone from the underside. The holes should be through the wood only and not make contact with the inlay. If it happens again you may need to remove the bridge and fill the holes and redrill.

The big problem is the holes. The strings are exerting upward pressure. The only pressure should be down and into the corner. Theoretically, the bone should be able to stay in place with no glue whatsoever. Once you re-glue it, make sure that the holes are re-drilled properly.

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Expectation is the source of all misery; comparison the thief of joy.
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Try this before you redrill the holes:
Once the strip is reglued, get the Dremel bit that has the tip shaped like a small cone and relieve the holes on the front side of the bridge by inserting the bit and opening them up so that the string does not push on the front edge.
If you can extend the cone shaped recess as far back as the wood, the string pressure will bear there instead of the bone.

Ok, here’s an update. I cleaned off the old glue and re-glued using CA. I didn’t have hide or fish glue. Also relieved the upper edge of the string hole as suggested. Restrung and it appears to be holding.



Thanks everyone for the help.

Also, if anyone is interested, here’s an audio clip I made right after the guitar was initially strung up, before the tie-block fix.

http://home.comcast.net/~jlulm/hauser%2 ... clip_1.MP3

I’ll try to record some better clips and post with some pictures in a week or so.

Joe

The fix looks good Joe.
I had a listen to the clip - nice playing! The guitar sounds like it has nice balance and a good bass "growl"
Excellent work! It will open up even more over time.

Rob

Sounds great, you can hear the newness in it but she will open up nicely in time.

Looks good - Sounds good! What more can you ask?

I really like the arrangement of "Scarborough Fair". Is it out of a book? If so, which one?

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Waddy

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Sound Clips of most of my guitars

Thanks for the compliments guys. Waddy, it’s David Brandon’s arrangement in the Christopher Parkening Method volume 2.

Joe

Thanks, Joe!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

design wise you could take a look at going double hole on your next one. that design eliminates the upward pull of the tied up section of string.

18 hole leaves a nice clean tie block, with no issues.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I'm with Waddy, 18 hole is the way to go. I put a bone plate on the back as hole reinforcment, this stops any tendency for the strings to cut into the back of the bridge.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.