Does any one know of a requirement on the number of threads a bolt should have when bolting down a attachment for bonding. According to URL if the size of conductor is a #6 wire then it should be secured by a 1/4 bolt, it does not state what is considered enough threads to have a secure hold. I have heard a minuim of three complete threads but I can't find anything to back this up with the way it is written it looks like you could get away with a half of thread as long as it looked secure.
Anyone one got any ideas?