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I'm building my first OM acoustic from the Kinkade book. I've glued all my tall braces, and shaped and scalloped them and cleaned it all up. Now I want to glue the flat braces around the sound hole and the bridge plate. In the book, he makes special mention that he does not glue the bridge plate on in the go bar press, but has another caul shaped to the same radius with a hole through it, so he can clamp it with big C clamps. (I'd rather not have to make ANOTHER jig here.)

The only reason I can think of is that he wants a lot of extra pressure to ensure that sucker's on tight.

I'm using a piece of straight grained maple sanded to the radius to fit nice, and glued with tightbond. The go-bars have done a sweet job thus far. Is this really necessary? The go-bars really won't have sufficient pressure? Even if I use many? I'm hoping it will be.

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Dee Tee

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"If something is worth doing, it's worth doing right."

It's all I do. Fit as many go-bars on the plate as you can, and you'll have hundreds of pounds in clamping. Not an issue...

Make a caul and set it on the plate and use the go bar and it will hold fine. I don't use this system any longer as I use vacuum.

stan , I have the vaccum clamping system, but have never built a jig for bracing, can you build a universal type system to fit different models or only 1 at a time .Where does one get the plans// thanks

Ernie, I don't know what kind of jig(s) your referring to.

I have a 24" x 24" aluminium frame. I put in on an old mold frame I used to use that I sealed. I have two radius dishes I cut up just oversize of the plates. I just set the plates on the dish, glue it up and set caul's on top of the braces and ends, turn on the vacuum ( I don't use an air compressor rig)

I am going to make a new base and hinge the frame to the base (some day when I get around to it, which has been several years now) I only clamp down the ends of the X braces, UTB, and the back braces. I have templates for the finger braces just for locating them, and they don't move around when gluing.

I am about to buy a couple more dishes and this time I won't cut them. I am going to use some pieces of wood and make little hold down clamps I can use on the brace ends This is how it was done at a shop I worked at and worked well.

They fit all models and the bracing in all models end pretty much in the same place. If there is a difference, I/we just made or moved the clamps or taped them down.

The Boss still uses go bars. I just have a small shop space and vacuum is easier for me. Just what one prefers.

Awesome. Thats kinda what I figured. My go bar press is home made, using 1/2"x5/16" strips of ash as the go bars, They're super strong and cauls are definitely necessary, as the leave marks. I've got a caul made up 3/32 smaller out of the same 1/8" maple. Using Titebond, so heating it up not an issue.
Plate is radiused to match my homemade go bar dish as well. Looks like I'm ready to go.

as for vacuum presses, not sure I understand exactly how that works, or that i need too. I can't really imagine a simpler method that the go bar press. Very traditional, It cost me 0$ to build, costs nothing to run, can be stored in my garage and easily set up when needed, and is brain dead easy to use. Complete rookie - 3 backs done, 3 tops nearly done - 0 hiccups.

Thanks again for your input guys!
This forum has been incredible.

_________________
Dee Tee

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"If something is worth doing, it's worth doing right."

I guess I'm imaginatively challenged but I don't get why "25 - 30" go bars are better in any way than a couple of big C-clamps. Any time you have a fairly large surface area, as a bridge plate, you want serious pressure. Screw clamps provide that, vacuum doesn't, go bars maybe. Vacuum works for smaller parts, like braces. I use it for those gluing jobs and love it. Go bars are good for the same type of jobs with only a few drawbacks. But when you need lots of psi, reach for the cams or screw clamps.

Franklin, who make Titebond, recommend 300 psi for well-fitted joints. That would crush a lot of guitar parts so we don't use that much, and if you're using hide glue you don't need as much. But large areas do require more psi than small, just to get the squeeze-out. One cam clamp can develop almost that much pressure if the gluing surface is no larger than the contact point of the clamp. Since that's not the case, you have to figure that you're only getting a fraction of the pressure at the glue line.

YMMV. Bridge plates don't ever lift or curl, do they?

I only use hide glue, so my comments are just stuff from inside my head.................so, With hot hide glue you HAVE to have the parts clamped before the glue gels. It basically only takes the pressure needed to hold the parts together. Once HHG gels it's.....stuck, (although not at full strength yet). It shrinks, after it's stuck. With any type of room temperature glue (even fish glue) it sticks while it is shrinking so more pressure, as well as longer clamp times are necessary.

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