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I've got a little problem with my first build. The guitar was actually finished already in March and I've been playing it since but now it's developed a problem.

When I prepared the rim, I sanded about 2 degree slope from the upper bout transverse brace to neck block. I thought I was smart when I had some extra for the neck angle but when the box was assembled and I started preparing the neck for gluing I noticed that I've got too much angle on the body for the neck so the fretboard climbs up from the neck joint. I sanded the fretboard down a bit and glued the neck and then sanded the fretboard some more until it was dead-straight. Now after a few months I've got the fretboard end climbing up again so I've had to sand down the last 3-4 frets.

This isn't quite enough so now I'm looking for alternative ways to bring down the top radius on the upper bout brace. I glued the top braces on the winter when it was really dry, about 20% and now that it's about 50% RH the top has substantial radius near the end of the fretboard. All the top braces were sanded to 30' radius and glued on a radius disc.

If the explanation isn't clear enought, I'll try to take some photos tonight but meanwhile does anyone have any suggestions how to flatten the top near the fretboard end? I could always pull out the last 7-8 frets and sand down the fretboard extension but it would look a bit awkward? The neck angle is fine and I've got the strings about 1/2" off the top but the problems is that I put too much angle on the body.

From this link you'll find some info on the guitar: viewtopic.php?f=10101&t=39896

Stevie: You say the strings are the correct distance from the top at the bridge but you did not mention neck relief or the action at the 12th fret. I'm just wondering if the body may have settled in a bit and the neck may need to be reset a tad. I have had guitars that required very early resets and then settled in quite content and remained that way. and I think 20% RH is too much on the dry side for bracing. The lowest I've done is about 35% and actually try to do the top in that area. That is a nice looking guitar by the way and hope you get your problem worked out.
Tom

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A person who has never made a mistake has never made anything!!!

Thanks for the replies! I assume the problem is that the body has settled a bit and the humidity is also at the highest right now so that bumps up the fretboard extension. On top of that I made too much angle on the body originally so all this adds up.

I'm just wondering if there's any secret way to straighten the radius of the soundboard on the region of the upper bout transverse brace? That doesn't even sound good so I guess I'll just take of the frets on the extension and sand it down with a radius block. It's only a question of half a millimeter but it looks bad to my eye.

It's no secret....just replace the upper transverse brace with a flatter one.
I deal with the opposite problem on old guitars. The top has sunk in the upper bout, making the fretboard drop-off too extreme. On a few occasions, I have replaced the brace with one that has more arching, and it works really well.

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John

That's a pretty big access hole for truss rod adjustment on your UTB, but if you are contemplating replacing the UTB I would first try to reduce the height and thickness of the one you have even if you don't have much wood left over the hole. If it doesn't work you can always replace the UTB with a flatter one.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

I'm glad I spotted this thread, as it has become kind of timely for me. I am almost ready to close the box on my current build, having cut the pockets in the linings for the brace ends. I put the the top in place and checked the straightedge height over the approximate bridge location and found it way too high. It appears the UTB has a smaller radius than I intended (60'). Either I cut it wrong (I don't think so), or the same humidity problem has hit me. The braces were glued on at 35% RH, and now it's 50% in my work room. Either way, I'll be removing the UTB. I've got a test piece gluing to practice the removal (fish glue). Any hints to make it go more smoothly?

Chris
PS: There is a 1/4" board under the straightedge in the 2nd photo to mimic the fretboard.