Cambered Cauls

[Sean Troy]

When using the Cauls, does the bottom one (Underneath Glue Up) need to be cambered or flat?

[Sebastien La Madeleine]

I use curved on both sides. It kind of makes sense if you think about it. Your top caul that is curved is going to push harder on the middle part of your bottom caul. If the bottom caul is flat, it will then deflect from flat, giving you a curved panel. Now, if your bottom caul is massively stiffer than the top on, you might be able to get away with it. (a 2"x6" maple caul on the bottom might not deflect even if your 1"x1" top caul is pushing on it)

Since all my cauls are of the same material and same dimensions, I use curved on both sides...

Hope this helps!

[Mike Henderson]

Sabastien's right. Both cauls bend when you clamp them down. If they're not both cambered, the result will be a curved clamp space.

Mike

[Sean Troy]

Thank you for the information. Another question, how long should the cauls be in relation to the width of your glue up? Thanks

[Mike Henderson]

Thank you for the information. Another question, how long should the cauls be in relation to the width of your glue up? Thanks
They only have to be as long as your panel is wide. You actually want to clamp the cauls just inside the panel. Actually, this is for convenience. It allows you to clamp one side and then go to the other side and put a clamp on.

If you put the clamps outside the panel, it really helps to have two people, with one handling a clamp on each end.

Most people make cauls in some standard length, such as 3 or 4 feet.

Mike

[Sean Troy]

Thank you all for the helpful information, Sean

[Jay Aubuchon]

If you put the clamps outside the panel, it really helps to have two people, with one handling a clamp on each end.


In this situation, I temporarily place a small piece of the panel material between the cauls where the first clamp will go. That way, I don't need a helper.