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I am building a new double side laminating form for a different model and decided to try a new way of making the cauls.

I cut the wood base for the caul and added temporary edges so it formed a receptacle. The edges have to be high enough to clear the curve of the body in the area the caul will be used.

Filled the receptacle with Duram's Rock Hard putty and pushed the whole thing against the form which was covered with clear packing tape. Removed the excess and let it set up. It was usually OK to remove in about 10 15"

The next day I cleaned up the cauls in the belt sander and cut off the elevated edges on the table saw. It worked great. I plan to cover them with cork as I have done with my other cauls.

I am sure most of you have used Durham's but it was the first time for me. I think it would be great for any custom clamping caul for a complex surface. It would need a wood backer.

I have to do some touch up work on the lower caul in the picture.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

FYI terry robert desmond has on his website 3 videos? of his side laminating jig he uses for laminating double EIR sides.

Interesting. I started with something identical to his "old" outside form and found it a little cumbersome to use. I then switched to what is shown in the picture, similar to his "new" form and actually did use the eyebolts and wing nuts at first. I still use eyebolts for the tight cutaway of an archtop.



I later saw a picture on Howard Klepper's website using the 1 1/4" holes and bar clamps. That is what I have used for the last couple of years. I have found them easier to use for me. I started with a deep enough hole to just use one clamp in the center but quickly found it was better to use one on each side.

I wanted to use shaped cauls and laboriously shaped them on the spindle sander. The Durham putty thing is much easier.

That said the narrower straight cauls look like they work just fine. Probably would have saved me a lot of work.

Thanks!

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Terry hindsight is always 20 /20 LOL. I have an old overholtzer mfg. alum side bending jig like charles hoffman in Minn. so I just use that for double laminations .I sometimes also use the inside part of my mold (ukes) ala J. bogdanovich and use 3/4in mdf cauls spaced all around the inside , by using either uf glue, or titebond, depends how fast I can get the clamps on and the air temp in the garage. I also use dunhams for carpentry /woodwork errors/repairs.

Here's a guy with kind of a unique idea. Just saw it yesterday on an AGF build thread

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I see you do use some kerf kore for some laminating cauls. I use a length of that for the entire caul. Do you find the block cauls work better?
I also thermoformed some corian to make laminating forms similar to what is in the last picture.

I do use the kerfed material for the cutaway caul for archtops but solid block cauls for everything else now.

After trying various approaches that has been the easiest for me.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

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Doug

Don't let fear or common sense stop you from trying to build something