Official Luthiers Forum!

Who flattens the upper bout and who doesn`t ? I can`t detect much difference either way.I use a 25` radius and always make sure the UTB is flat and glued on flat.It seems I have more trouble leveling frets when I`ve flattened than when I haven`t ,with more of a hump where the frets meet the body.I`ve never had a problem with any guitar that I haven`t flattened and I seem to have more trouble with the ones I have.So why Am I doing this?Any big advantage? I don`t seem to be getting it.
James

_________________
James W Bolan
Nashville Tennessee

Funny, I had the exact same thoughts last night. I'm assuming you're talking about flattening the rim set in the upper bout of an otherwise radiused top? This is what I've been doing lately thinking it would be better (it just made good sense to me and had some good recommendations). I'm considering going back to radiusing the upper bout on the next couple and just flattening under the fretboard extension.

I'm interested in hearing some responses, too.

_________________
Wes McMillian
Santo, TX
http://www.wesmcmillian.com

I just flatten under the fingerboad. Works well for me.

_________________
Jim Watts
http://jameswattsguitars.com

I also have built both ways. And have good results with a 28' domed top including the upper bout. The only difference I see is that the waist is a little deeper than if flattening upper bout. You do need to take this into consideration when gluing neck and tail blocks. I prefer an arched UTB vs. flat, which is the result with a totally domed top.

Chuck

_________________
_________________

I flatten the upper area only under the fretboard .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Filippo may have answered my question but Todd you use a dish to radius the top of the UTB? I like the idea of a slightly radiused UTB to add a little stiffness with no little to no weight penalty. Before seeing Fillipo's post I would have guessed it would be difficult to get an even, subtle curve without a dish. Filippo, do you mark a 60r line on the UTB then plane to it?.....or do you have another method to keep the curve even and about the right radius?

_________________
Formerly known as Adaboy.......

The 60` deal seems like a good compromise.Who came up with that?I feel so dumb around you guys.
James

_________________
James W Bolan
Nashville Tennessee

I use radius blocks....no dish. After roughing out the radius on the brace with a hand plane, I put sandpaper on the block and sand the brace until it produces a fair curve. The same block is used against the top when gluing the braces on. The block I use for the UTB is somewhere around 60 foot radius, but IMHO the only thing that is important is to achieve a straight fingerboard. My method for building is to glue a radiused top to flat linings, and I need some radius on the UTB so that the fingerboard comes out straight.
I also like at least some top radius in the upper bout for strength. The combination of longitudinal compression and downward force can cause the upper bout to sink in.
The alternate methods.....radiused lining or beveled upper bout (Martin style) combined with a straight or nearly straight UTB also can work, but after 24 years of success with my method, I doubt that I will change.

_________________
John