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So I'm brand new to guitar building and to wood-working to for that matter. I just started building my first kit - a StewMac OOO kit. Everything was going swell until last night when I started looking at the sound board braces. The OOO kit just comes with two square pieces of wood and the blueprint to make the x-braces. However, I'm not exactly sure what the best way to stencil the shape onto these braces is. Once I've got that figured out, what's the best way to cut the braces? And if you're still reading, what's the best way to radius the back and round the tops?

I have quite a few tools. I have a little saw. A ton of files, some good knives, etc. I don't have a plane, but I'm not sure if I need one. I'd really, REALLY appreciate any tips you guys can give me!

P.S. I'll explain the photo: The two plain looking pieces of wood are what I'm supposed to make the braces from and need help with. The two braces are x-braces for a dreadnought guitar and just there as a reference. They're too long to trace though. Just good to look at.

Trace the brace curve onto a thicker piece of paper, cut it out, tape it to your brace blank, and then you can trace the pattern onto the brace.
A plane would be useful for shaping the curved glue surface of the brace. I glue my braces on oversized and shape them once glued. It is easier to clamp a rectangular piece of wood than a profiled, scalloped brace. Plus, you can get a nice tight lap joint on the X brace if they are not shaped.
You could always cut up your blue print and tape that to the brace as well.

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http://www.CostaGuitars.com
PMoMC

That's great advice. So following your suggestion, I would use a plane to shape the bottom of the brace, glue it on, then shape it? What about the point where the 2 braces intersect? Just leave the intersection unshaped?

Yes, keep the area of the joint rectangular. You'll want maximum material there.

I cut my braces on a bandsaw, then I radius the bottoms on a router table with a flush cut trim bit & a template. After gluing to the top or back, put a sort of knife edge on the tops of the braces with a hand plane then scallop with a chisel.

How are you going to glue the braces to the top & back? Do you have radius dishes or cauls?

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

What klooker said.
And yes, shape the glue surface but leave the rest of the brace alone. Shape the top of the brace after you glue it on.


Posted using two tin cans and some string.

_________________
http://www.CostaGuitars.com
PMoMC

Great advice, Kevin. Thanks! I ended up running down to Lowe's to buy a little plane. The file was working to some extent but wasn't making a very even surface.

I have a 3/4" piece of plywood that's the I cut to the same size as the soundboard that I'll rest the soundboard on, as well as some clamps and cauls that I'll use for gluing. That should work don't you think?

Good suggestions above - here are a couple more. Take your blueprints to Kinkos or an engineering office and get a couple of full scale copies made. You can cut them up to make tracings and still have the original.

I radius the glue face of my braces and rough shape the tops. After gluing them on the top I then scallop with a good scary sharp chisel. Ends up looking kind of like this

The StewMac kit I bought came with full scale blueprints, so I'm set there.

What's the best way to ensure you get the proper radius on the glue face? I got a few sample x-braces with the kit (dreadnought size) and I just traced the radius onto the actual pieces and planed them until they seemed to match the sample piece's radius.

The top is usually radiused at something around 22-25 foot, the back about 15-16 foot (different people use slightly different values ) The very best method is to buy or build two radius dishes - you can use them to sand your braces as well as to back up when you clamp. They are expensive and you probably don't want to buy them for one build.

On my first I made a couple of radius cauls - took a piece of 2x2 scrap and traced a 24 foot and 15 foot arc on them, sawed them on a bandsaw and use them both for sanding the braces and for backing up when I glue them to the top and back.

The last method is to simply trace the curve on your brace stock and sand to that line. I would clamp all the back braces together and sand them as a unit, do the same with the top X braces. The exact radius is as important as having some (flat top guitars are not really flat) and that it be smooth so you get a really good glue seam.