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I am on #9 and have been using a Gibson brace shape/profile. I have been making the angled sides with a hand plane before gluing them on, and they come out fine, but there has to be a better way. I have not figured out a good jig for a table saw, and the one I tried for the bandsaw does not have enough accuracy. Someone posted a cool router jig that they use after the braces are installed, but that is a bit elaborate for the number of instruments I make.

Does anyone have a good jig for shaping braces before installing them?

I do mine on the table saw use a zero clearance and feather boards

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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

The Gore book has a super easy one to make that uses a router and chamfer bit. Do you have access to the book?


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I put a radius on the bottom first, then hog w a bandsaw then a spindle sander you get closer... BUT... I fish shaping them w planes and chisels after they are glued to give me more flexibility in how the top moves after it’s all said and done



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Here’s how I preprofile my braces. Mind you I’m cutting 100+ pieces at a time which is enough for at least a dozen guitars.

https://youtu.be/C_5q7PEd-jQ

Here is a pair of jigs you can make for a table saw to angle the sides of braces. I made one for cutting the "angle" portion on traditional kerfed linings (the off fall I use for tentalones). They are just blocks of wood that can be clamped to the tablesaw fence that have slots cut in them to feed the stock through into the angled saw blade.

I was doing the initial shaping of some of my braces using my drum sander with a complicated version of how Michael does it. Once I saw his method, I stole it and adapted it for the drum sander. (Thanks, Michael.) I made a carrier for the brace blanks with two angled channels on it that rides the feed belt through the sander. A brace blank goes in the channel on the left and goes through the sander. Flip the brace end for end and put it in the channel on the right and back through the sander.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Don't you end up carving a profile on the braces anyway once they are glued down based on stiffness testing or tap tones or shamanic visions? Does this method just sort of give you a head start on that process?

Yes. I don't know how one would glue a pointed brace on.
Sharp chisel, favorite part of the build for me.
Alan

Everyone - thanks for the good ideas

Alan

I agree that shaping is a fun part for sure - I am just getting a head start on it. I use little blocks with a "V" cut in them that fit over the top of the braces

Ed

This is how I clamp pre-profiled braces.

Are you all doing this to the x braces too? How do you handle the intersection of the x where there shouldn't be gaps between the two braces? I haven't figured out a good way to preshape these braces. I fit the x lap joint on the squared stock, glue them down and cap the lap all before I start to profile them so I can get a decent transition from squared to profiled. I'd love to know what you all are doing.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I clamp my X-brace like this.

Then I profile the x-brace with this router jig.

5 minutes later it looks like this.

Best, M

In my case, I pre-profile the upper face brace, the tone bars, the sound hole braces and the upper two braces on the back. All the other braces get profiled and shaped with a chisel after they are glued on. I use vacuum clamping so gluing the profiled braces on isn't a problem.

jfmckenna - Of the braces listed above, only the tonebars benefit from shamanic visions. They get added attention after they are glued on. The main thing done to the other pre-profiled braces is carving the ends down to tuck into the lining. So, yes pre-profiling those braces on the drum sander gives a head start and its possible to prepare lot of them fairly quickly. Not as quickly as with Michael's set up though.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I took Kent Everett's voicing class five years ago and he leaves the braces on the top flat and just sands them smooth when he's done voicing. I've been doing the same ever since. Not to poke holes at those that want parabolic or triangular shaped top braces (I did that too for over 10 years) but just wanted to make the point that you can leave them rectangular in cross section and they work just as well. Of course I do shape my back braces since they can be seen through the sound hole, rectangular back braces are glued on then shaped with a chisel, plane and sandpaper. Just another option.

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Steve Smith
"Music is what feelings sound like"

Same... ^^^^

Yeah - in Somogyi’s voicing workshop which I attended in 2012, he was profiling his braces in a ‘Eiffel Tower’ shape. There was no way in h*ll I was gonna spend the time to do that, so I settled on this approach. It doesn’t really take me any extra time, and it removes a bit of mass so I’ll likely stick with it.

Best

I wonder if you could get the Eiffel Tower shape with a different bit?

Michael, that is a very nice profiling jig you've got there.

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Steve Smith
"Music is what feelings sound like"

Indeed, a fairly large diameter ball nose bit would make a nice shape, like this:

Although it's really not enough weight to matter on 5/16" braces.

You could probably do it by using a cove or panel raising bit and making a couple of jigs to hold the work and select out the section you want to use.

Yes, It's absolutely possible but not really worth the effort IMO. I think for Ervin it was an opportunity to show off his skill.

Cheers, M