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I spent my holidays making up a router table and jigs for bulk producing braces. I had intended for the x's height at intersection to be 11/16", but somehow they end up at 9/16". I'm sure that's probably fine, but I'm curious to know, what are your starting height at intersection for your x braces?

I think 9/16" is the most common height.

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David Malicky

I don't mind being common....

Actually 9/16ths is fine.

I start at 5/8ths, and carve down to 9/16ths, but if I need to leave them tall I can.

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Old growth, shmold growth!

With few exceptions, Martin 000 and dread x-braces are 5/8" tall at the intersection. 1/16" does not sound like much, but it is a huge difference in stiffness, which is proportional to the cube of the height. Martin D-35's sound different from D-28's....mainly because their braces are 9/16" tall.

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John

Suppose I can just shim the bottom of the template....

currently i'm at .75 x .22 approx. to start. with a parabolic profile and tapered and un-tucked. i tend treat guitars as individuals though -bulk isn't really my thing.

I'm at .625".
Tom

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

I've got a lot of orders on the go. While I enjoy the whittling with the micro plane from Stephen Boone (it's actually my favorite part), it's time spent that's not really necessary. Especially since I try to make the taper as consistent as I can from guitar to guitar. If there is a need to deviate from that, I still have the planes. And since the height is the major adjuster and not the taper/bevel, it makes sense to me to have a bin of radiused and tapered brace stock ready to grab and glue...

A notable difference these days is that many of us cap the X-brace intersection which, I assume, has a significant effect on the stiffness of the top at that point. To what extent should this influence our design decisions where height at the brace intersection is concerned?

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Cheers
Pete

Good question....

A couple of weeks ago I bought a 1934 Gibson L-00 for the princely sum of $41. Problem is that someone had punched through the back. However, this allowed me to get inside and measure the bracing and seeing this has changed my thinking. Check the picture - the top bracing is 3/16" at the base, a little big if 1/16" at the top, and 9/16" tall, including the "X". The back braces are 1/2" tall and a little wider, but no where near 1/4".

of course this is a smaller guitar, and braces this light will effect the sound.

Ed Minch

Well, I made some shims to modify the jig.

UTB = .500 x .625

X's = .250 x .600 Dread, AJ, SJ, .250 x .560 OM and smaller.

We've also started toying with deflection testing the brace stock too which has been illuminating...