Well, this will probably not be the popular answer but when one of mine decides to try to bit me I take what they have away from them right then and there and get my duct taped, reinforced, rolled up newspaper and they get a swat or two on their butt end. Not hard to hurt but enough to let them know this behavior is not acceptable. I never use the crate for time out because I don't want to confuse them and want the crate to be a positive experience and safe heaven for them. The swat usually ends up with them running to their crate and looking out at me......then I firmly tell them no, bad dog.....which usually ends up with them looking down at the ground. I wait about 5 minutes and call them over and we make up......usually get a toy and play to let them know we are back to good graces. Most of the time a firm "NO" will suffice but on the "rare" occasion it does not I have had to resort to the newspaper. I hope everything works out, good luck!