I decided early on that I would use internal and external stems on my boat....... my first boat. I also had no clue on how to achieve the rolling bevel with any tool. It seems I always cut crooked. Must have a crooked eye.
I found a huge help on Michne's boat page. Sand paper-on-a-stick is the answer for those of you with a crooked eye (and it does take the fear out of a tricky bit of wood removal).
http://michneboat.com/Web%20site%20home.htm
michneboat here are a few pictures