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I was thinking of leaving the upper transverse brace flat( as opposed to 25' radius), to allow for an easier neck connection .

I have already shaped the sides in my mold on the 25' sanding dish...so the question is with the neck block sanded to the 25' angle( when the sides were profiled), will a flat upper bar become a problem when I glue the top on.( The sides will be profiled to 25' but the top will be 25' radius-ed below the soundhole..but actually be flat above the sound hole..does that make sense or I am confused?...again...)

If you were going to used a flat traverse bar wouldn't the kerfing above sound hole position,and heel block also have to be flat to get a good top -side connection?..sorry I have a terrible time visualizing this..

Thanks

 

Thanks for any help...

You can lightly sand the neck block and upper bout region using a flat sanding board - this will help with the fit of the flat upper transverse brace. I was taught to do this by putting the top edge rim face down on a sanding board, jack up the tail block using a flat spacer, and lightly sand what's still in contact with the paper to get a flat surface in the upper extreme of the upper bout. I'm digging for the thickness of the spacer - I've been building classical guitars ever since I did this the first time and can't remember the number now. (Wasn't that helpful?    )

Jim

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Jim Kirby
kirby@udel.edu

Per a posting by Hesh a month or so back, I used a 1/8" spacer on my current build and it worked well.

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Jim Howell
Charlotte, NC

So, call me a dummy, but do most builders here put a 25' radius on their tops? I've made 1 Weiss style, with a dead flat top, and maybe I should have put a nice arc to it. I did make one squareneck, with a radical arc, on the top and back, and that thing is pretty loud. Any info would help, thanks. Alan.

I radius my rims but use a flat upper transverse brace

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Andy Z.
http://www.lazydogguitars.com

Thanks guys...I think I remember Hesh's posting....I'll try to look it up...

 

Andy..do you find it a problem when it comes to getting the fingerboard extension to lay flat on the top ...do you sand the top flat where the extension is or use some other method for a good fit?

I use a flat transverse brace. Here is how I get everything to work out.

I sand the rim of the top on a FLAT workboard. Once the linings and sides are dead flat.

Then, I mark the neck block, sides and linings down to the upper transverse brace with chalk.

I put a .150" shim under the tail block and sand the neck block and upper bout by "swinging" the top of the guitar back-and-forth on the flat work board until the chalk marks are gone.

This help set the neck angle

Once the top is on, I use a flat sanding block to flatten the area under the fingerboard so it is dead flat.

Slight adjustments to the procedure are necessary for different body sizes, but these work pretty well for an SJ size guitar.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com