How tight do you tighten a record clamp

On my VPI I tighten the clamp until the platter turns and then hit the start button.  It works.

I barely ever use the clamp on my VPI. When I do use it I make sure not to make it too tight!

Put a rubber washer about 1/8" thick down over the spindle, then put on record then clamp. That takes out most warps as it dishes down against platter slightly. 

8.7 Newton.meters of torque.  No more; no less.

Lew, … I have a VPI steel clamp.  I am a bit OCD about the torque like you.  I use a piezoelectric laser torque gauge when I tighten the clamp down.  But I only tighten to 7.4 Newton.meters of torque. Should I put more torque on the clamp? Now you have me concerned.  lol