Australian/New Zealand Luthiers Forum

I wanted a way to more easily clamp my bridges down, and came up with this. Mainly because my hands are pretty big, and manoeuvring clamps and blocks and calls, etc was really awkward for me and resulted in more than a few cursing sessions....

There is a block inside that is radiused to the top. Two 3/16 bolts pass thru the locating pin holes, and tighten with wing nuts. The two screws on the end have a nut inset into the bottom of the clamping caul, and bear on small hardwood blocks to clamp the wings down. This is also a more or less single type of guitar jig, but it's easy to make, so I'll just make more as I go along.

Hi Nick,

Looks good! I too find it hard maneuvering things inside the body, accessing through the soundhole.
Any chance of more pics? ie the bottom piece.

Thanks,
GregL.

Will do tomorrow, Greg. Right now, it's holding the bridge on while the glue dries

I can tell you, I took a scrap of decking, I think, and fit it to the angle on the cross braces. I located the outer pin holes and drilled a bigger hole, to allow for individual variations. I just put the caul into the intersection of the braces, and the holes line up....neat.

Next thing I'll do is shape the top caul to the shape of my bridge to allow for easier cleanup. Nice not having the clamps to dodge.....

That is actually an old and true design , but to make it even better, you use 3/8 heavy silicone padding under the bridge area , then you can get toggle pads at most home depots or lowes , the toggle pads are great for working the wings.
Also you may want to make a inner cawl so you don't over stress the top from the wings .

Greg, here's the little critter off the guitar. By the way, this is the nicest glue up of a bridge I've had, tho I also changed a few other things I was doing to prepare the top for the bridge.

John, I probably saw some version of this somewhere, and copied it. The caul supports the entire bridge plate area, and so far as I can tell, the wing clamps are landing on the X-brace, so I'm happy with that....

The real trick, I found, and as you know, is to get a really good fit between the top and the bridge, which I fit before shaping and had a much better result.....

I spent many years as a carpenter/builder and all my jigs and such were one-offs for a particular job. I've now started making jigs that I can use over and over, so I want them to be a bit more comprehensive....

Hi Nick,

"Greg, here's the little critter off the guitar."

I'm sure it's my eyesight failing, but I can't see the pic.

Thanks,
GregL.

Nope, my fault....

Hi Nick,

Thanks for the pic. I'll study it.

Thanks,
GregL.

Nick,

I think John may be suggesting the fit between the 'underside' of the top and its caul to avoid crush damage on the ends should a flat faced inner caul be used on that radiused surface. For bridge fit to top I sand a 1/2 sandpaper sheet size piece of mdf to profile in the appropriate radius dish, glue on some abrasive and use that to cut the basic shape for the underside of the bridge. Then at the same RH to that which the top had been glued on, I tape a sheet of abrasive (wet&dry cause its thin) direct to the top itself and finish off the profile with a light sand right were the bridge is to be glued.

Cheers

Kim

hey Kim,

I fit the bridge like that too. Makes a nice tight fit, and the internal caul is radiused to match the top on the clamping surface. Best result I've had yet, and I don't have to wrestle with clamos, blocks and other bits thru the soundhole.....

Kim wrote:Nick,

I think John may be suggesting the fit between the 'underside' of the top and its caul to avoid crush damage on the ends should a flat faced inner caul be used on that radiused surface. For bridge fit to top I sand a 1/2 sandpaper sheet size piece of mdf to profile in the appropriate radius dish, glue on some abrasive and use that to cut the basic shape for the underside of the bridge. Then at the same RH to that which the top had been glued on, I tape a sheet of abrasive (wet&dry cause its thin) direct to the top itself and finish off the profile with a light sand right were the bridge is to be glued.

Cheers

Kim

Sounds like the right way to do it, all the variables addressed/taken out of the equation.

Steve

This is my Soprano bridge clamp.

Can you show us a bit more of that clamp Ken. Love to know how it works.

You place the top caul on the bridge turn the knurled knob...and the lower caul rises up to the bridge plate.
I made this one for Pete Howlett...but I don't know if he uses it