Sojn:
  Have you seen the mandibles on a female carpenter bee?  Now *those* are
mandibles.  I suppose a rough guess could be made about force based on the
wood that they chew through.  I don't know if anyone has measured this.
My guess would be that if you caught a female carpenter bee and put her in
a cage, she would try to chew her way out.  And if there wasn't much to chew
on in the cage except a thin piece of tubing ....
  Sounds like an interesting project...  or just another event for the bee
olympics...
 
Marty