Bill,

What is the CA glue for?

The glue on the label is just so the paper doesn't move around while the part is being placed in the vise. The huge PSI from the clamping action will ensure that that the paper doesn't move when in position.

Looking microscopically at the part's and vise's surfaces, there are hills and valleys. The thin layer of paper will compress more on the hills and compress less on the valleys. Yet, even in the valleys, there will be a lot of friction.


Marv,

As for using very fine sandpaper, I wonder if this might actually not hold as well since the grains will stand between the surfaces. On the one hand, the total contact area might be reduced. But, on the other hand, each grain will be bedded into the part's and vise's surfaces and can't move around. Now, this does assume the vise jaws are aluminum. If hardened steel, the grains might just slide across the surface.

The sheer force might have to be totally resisted by the grains and not by friction between the part and vise.

Depending on your definition of "very fine", I wonder if this would mar the surface.

I just finished a part that was 1/2" tall. It was clamped by the bottom 0.05" and I used this gummy label trick. Nothing shifted. Now, I did not try making the part without the paper nor did I try making more aggressive cuts to increase the sheer force. However, using paper is increase grip is a very old trick that doesn't need proving.

Rick