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