I was going to do something like this until I got the Sorby Pro Edge, now I just chuck on an old belt that I have put to one side for this job, and no matter if it's a round or square blank they all sit against the gouge jig at 90 deg every time. love it.
edited to make it read as if English is my first language.....which it is, not that you could tell from the original message.....!"