have you thought about using dremel to grind his nails instead of cutting them? i took milu to petsmart the other day, and they used the dremel to grind down her nails. it seems safer to do it that way.
a groomer had cut milu's nail too short once and it bled a lot, she cut it so short i dont know why she wasnt even paying attention or what?
you want to make sure you don't make thor dislike getting his nails clipped. otherwise he will start fighting you everytime you try to cut his nails.