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http://www.woodcraft.com/product.aspx?P ... milyID=321

Has anybody tried this to top and backs?

Mike

For the price of one of those you can make a string and wedges clamp that will work just as well, if not better. I have a 4 wedge jig .. that would cost almost a 100 bucks to do using those .... plus you need the wood ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

It won't work. I have something similar and the bar the pushes the two boards together is 1/2" thick. If you use it on a guitar top, the wood bars won't press down and level the seam.

The idea is good, but I'd want to be sure the system works well for wood as thin as guitar tops. My gluing fixture uses three big clamps to apply pressure on the joint with four metal bars clamped on top of the pieces and an acrylic plate below providing support. That keeps the two pieces absolutely flat and inline with eachother on the acrylic side (I only flatten one face of the set pre-joint) and lets me clamp 'em good and hard.

The cabinet clamps cost some cash, but the rest of the fixture might have cost $40 (it was made from scraps I had around the shop anyhow). I got the idea from a similar jig Peter Marreiros uses.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Tony,

I already made the "Spanish Clamping System" and I like it OK, but there must be something I am missing. I made mine bigger to accomodate harp tops... but it can be used for small tops. According to the plans, you set the boards to be joined on the bottom ribs then wedge ribs on top. Problem I have, is there is not much "seam" support between the ribs! Do any of you use a piece of rigid material above and below the top? Seems plexi for the top might be better so you cna see the seam.

Thanks Mike M for the info.

Mike

Oddly enough I dont have a clear pic I can find of my string and wedge jig. I mounted 4 - 1 inch aluminum square tubes to a piece of scrap ply, about 4 inches apart, parallel. The ply is maybe a foot across, so the string can slide in to do narrow tops. Its about 18 wide/long in total. Across the centre seam area, i used smaller pieces of the same tubing, so I can press the seam down flat as I tighten the wedges. It holds/flattens out slightly curved and potato chipped tops or backs just great.

here it is in action ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

OK, so you do use a solid base.

Makes sense.

Mike

Yes, it will work! But you will need to make the follow modification:





Good luck!

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Tracy
http://www.luthiersuppliers.com

Check out this guys clamping method: Three bar clamps, 3 cheap wooden jigs, and a piece of UHMW (or plywood with wax paper)

http://www.acousticguitarforum.com/foru ... 585&page=4

While you are there check out the whole thread...Very cool.

Ray

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Guitar Building = Continuous Improvement Process

That's what I was trying to describe above. Mine is the same basic design.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

What's wrong with just using a tape?

Someone mention that these won't work because of minimal thickness and this is true. I have a set and their great for making electric guitar bodies and for other woodworking work.

Mike: Sounds like your system is similar to Tony's.This is also what I do,stole from the late Bill Lewis. Bob's system sounds very solid also. Think a lot of people join tops at a thickness close to finished size. I prefer to work with thicker top wood ,even close to .200 thou and thin down after joining. One thing to remember is if you have a displacement of .020 thou on one side of the top ,you have to remove twice that to clean up both sides. Think this system you asked about may work with thicker wood ,but as the others have said ,why bother. Use one of the time proven methods and invest in some nice wood or hand tools.

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A person who has never made a mistake has never made anything!!!

I have a 10-22 sander and have never attempted to sand anything wider than 9" or so. I know you are suposed to be able to do it. And it makes sense to join a thicker edge since the whole thing has more rigid stability. Might try that.

Thanks,

Mike

Always glue the plates together and then thickness the whole plate. I made the mistake of thicknessing the plates unglued before. For one thing if the joint is a little off it will be sanded level when thicknessing. Then there is the fact that you can't check the plate stiffness if not glued up. For tops and backs that aren't thick like an archtop all you need is a roll of scotch 233 tape and some HHG.

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