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I'm just a beginner at this game, but it struck me that you end up with a lot of offcuts at the edges of backs and soundboards which, laminated double thickness, would make very stiff and serviceable braces. Two layers of quarter sawn wood glued so the grain is continuous comes up pretty stiff when I try to bend it. Since people use carbon fibre (graphite) bracing what, apart from tradition, would stop any of you from using this? I got this idea when I had a back delivered that had a bad split developing, (the vendor sent me a replacement) - I decided to expriement using the defective back plate which was African mahogany and the resulting brace is very stiff. When sanded you can see the seam but I dont see this as a problem

Any thoughts? Or am I just being a cheapskate?

I should add that I am making ukes so the depth of the brace at max 10mm seems ok for smaller instruments.

sounds like going against the grain. I say go! Lighter stiffer bracing is a winner. Make it look like one brace. Be a cheapskate. Just build em!

Take a look at Haans bracing that is laminated around a darker veneer if the glue line bothers you. A photo and explanation in a similar thread is at:

viewtopic.php?p=346460#p346460

cheers

Thanks guys. Seems the idea has some support from people that know. I'll give it a try.

Won't laminating offcuts from the top like that make the grain run in the wrong direction if you want your braces quartersawn?

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Jonathan Kendall, Siloam Springs AR

There's some confusion in this discussion because braces can be laminated in different ways. Gluing quartersawn offcuts on top of each other keeps the grain orientation correct. The orientation of this looks like:

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This "leaf spring" bracing is what truckjohn referred to in the discussion mentioned above, when he wrote:


I would add that the technique uses a glue that dries hard and doesn't creep, such as HHG. I personally haven't used this bracing, but I'm saving soundboard offcuts and maybe one of these days I'll have enough to try it.

Yvonne, the only question I would have about your use of offcuts is that they aren't spruce so may not be optimal braces. But certainly they should work.

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Tim Allen
"Never hurry, never rest."

There are folks that laminate the braces as you describe. By alternating the laps at the X joint, it makes for a very stable joint. I did it once, but carving the braces was pretty difficult, with all those hard glue lines & I haven't done it again.
If you don't like arching your braces, it's a good way to get around that step.

What I had in mind was quarter sawn offcuts stacked on top of each other, as Tim illustrated. I was thinking only of using soundboard offcuts for soundboards, and hard wood for backs, and only two layers otherwise there seems a lot of glue involved and knowing me I would get in an unholy mess.

Just off topic I attended a course with Charles Fox recently, and he shaves his braces away to nothing where they meet the linings, no cutting of notches. He also uses a parabolic shape - I think that is the right word, like a half moon, very elegant looking, tapered to a sharp edge in the cross section a little like a gothic window. I wonder if laminated braces would be particularly good for a small instrument like the 5-18 copy I am about to make, as the stiffness relative to mass would hopefully be better. Mr Fox also doesnt worry about exact joint for the X bracing, he just butt joints them. If it is a tight joint I cant see why it should not be just as effective, it showed me it doesnt have to be difficult to be good.

Often there is runout, even a lot, in soundboards. You should definitely split these slats not cut them so you could easily see the grain.

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Build log

I like the idea Yvonne! Don't know about scalloping, but tapering should work. I rough out my triangular shape on my edge sander so if you have one, it would make shaping the bracing easier. I think I would try it.

I'd say just start by learning how to find the runout and use standard bracing practices including the X capped lap joint. Why experiment on time proven practices until you are more knowledgable about building and voicing the tops. You have to walk before you can run and the top bracing isn't the place to start out with a practice run. That's just my opinion though.

I use this system for backs. By alternating strips as already described I get a * instead of an X. Plus, you can press them into the dish and let the glue hold the radius rather than sanding the radius in.

Here's a couple shots








Dave

I certainly agree about walking before you can run and if in doubt I try to copy the industry standard, but Chris, the butt joint for the X bracing wasnt my idea, it's Charles Fox's ( not that he would claim he invented it Im sure). It seems that the stiffness is the key to achieving a good outcome, but you can achieve that in different ways.

"It seems that the stiffness is the key to achieving a good outcome"
Oh if it were all that simple.
If your top is over built or over stiff it will sound pretty dead. It's easy to stiffen a top and over build. If it's too stiff it won't move. The key is getting it to move in a way that produces the sound qualities that you want to achieve. You really don't want a fingerstyle guitar to be voiced the same as a bluegrass or strumming guitar.
As far as the lap joint and the butt joint, there was a long decussion on that a few months ago here. Each has their own opinion on it. It will be interesting to see if Charles Fox goes back to the lap in the future but that's his choice.
You can laminate CF vertically in braces but if you use much over .020" it will make the braces too stiff. One of the reasons for CF in braces is because it has a memory and helps the brace to keep it's shape over time plus other possibilities. Mario Proulx is the one to talk to on that subject, he's been doing it for sometime and has built quite a number of guitars with and without CF braces.
Either way good luck with your build and enjoy.