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Well some of you probably read the thread I started last week about speeding the drying time on KTM. Well that was really helpful, but I don’t have the space for a drying box of any kind right now. So I had to respray the face of a peghead a little while ago and thought I would try another sugestion that I have had from a few people (on and off this forum). That was to let the neck dry in the sun for a few hours. I figured that I would give it a try. It couldn’t hurt right (wrong! ). So I stuck it outside this morning and checked on it periodically. It appeared to be doing just fine.

Well I brought it back into the shop this afternoon and was going to test fit it to the body. I began to work with it and noticed something strange. I had a gap between the body and the tongue of the fretboard on either side. This was weird because I have never had this problem before. Well it turns out that my tongue of my fretboard has gone slightly concave. And now I don’t know what to do. One thing I know is that I am never going to stick anything outside to dry again. At least not in the direct sunlight.

So now that I have made this stupid mistake does anyone have any suggestions on how to fix it??? I was hoping to have this guitar done in the next few day but that will depend on if this problem can be solved. Any help would be appreciated.

And I guess the moral of this sad tale is, Don’t leave your neck in the sun. Your fretboard could go concave. Or you may get a sunburn.

Josh

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

Maybe some of the very experienced guys have a better solution, but you could try clamping the extension between two flat blocks, for a day or so and see if it can be pursueded to come back into shape.

It won't clamp out when you glue the extension ?

moisten and heat the cupped surface and clamp flat to a flat rigid plate such as aluminium or steel in place of the top. may take a couple of goes to get it flat again. you may also need to place a strip or two of masking tape on the plate centered on the cl of the fb extension to very slighten over bend to allow for spring back upon cooling.

crazymanmichael38552.6783564815

Just the man I was thinking of

I have the extension moistened and clamped and it seems to be helping. I will try some heat in the mix and see if that helps even more.

Keep the suggestions coming.

Josh

_________________
Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

It may also come back on its own if you give it a little time. It probably moved due to the humidity differences between your shop and the outdoors. This probably isn't what you want to hear though.

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Jim Watts
http://jameswattsguitars.com

So the side that meets the body is convex right?

This happened to me on my first (bought some ebony that must have still been a bit green), I tried clamping and heating, and ended up with a small crack. As a last resort, I put some CA on the crack, made up a sanding block out of mdf that allowed for the truss rod, and then very carefully sanded the hump out of the under side - being very careful not to remove any material from the fretboard edges. Probably not ideal, and probably means that the fretboard radius is a little flatter over the body, but you can't tell by looking at it or playing it (I know it's there tho )

I should add, that the hump was only about 1/32" high or maybe a bit less.PaulB38552.7897916667

when you want to bend wood you need heat, and straightening cups is bending; don't hesitate to apply heat to the extension. it will make the wood more plastic.

the cupping was probably the result of differential drying in the sun; the top side getting more exposure dried out more and contracted, therefore cupped.

I've had this happen before due to some blacklights in an enclosed box.
The fingerboard cupped bad. I re-humidified it and let it sit for a couple
weeks. It flattened back out.

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John Mayes
http://www.mayesluthier.com

Well I have good news to report. After letting it sit clamped in the shop for a good 6-8 hours it is almost back to normal. Looks like with a bit more time it may correct itself. Thanks for all the tips they were useful and may come in hand should this ever happen again.

Josh

_________________
Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com