This clamping system has been on my mind for some time and yesterday I set out to put it into reality as I started a box and thought I put an end to the frustration of clamping a box and still get the odd box that is out of square and have to rework it .
This clamp or clamping jig is a breeze to make and also minimal in cost aside from the Bessey clamp which I will use for other things anyway .
The design idea has several criteria which are simplicity, low cost ,accuracy ,visibility of the corners during clamping and smooth and accurate operation and no damage to the corners, I think I have met that goal .
I started with some plywood squares cut perfectly square and pinned two of them face to face and laid out the three hole locations and set up the drill press with a stop block to ensure all the holes where in the same location on all four corner pieces . This was followed by cutting out the right angle piece which contacts the box , the cuts were made with my table saw sled and have to be a perfect 90 DEG.
The steel pins are made from a piece of drill rod and the copper spacer sleeves are 1/2” copper pipe cut to lenght .
The copper sleeves serve a dual purpose as spacers and also as rollers to let the strap slide smoothly as clamping pressure is applied
The strap is nylon from a hold down strap and the clamping arms are again made from Baltic birch ply .
This clamp can be used on a multitude of box designs by altering the corner shape to accommodate dovetails or finger joints etc.
The box that I am making was cut on the sled also and I did a blog and video you can see here
and I also did a video that shows the clamp in action and shows more of the clamp build and the clamping process .
I included some random pictures also and hope you find this interesting and enjoy the video .
Any questions and comments are always appreciated .