This is what I came up with, copied from Steve Schlumph. I can see I may have to find a smaller knob to lock it on the ways, as there are some braces underneath that the current knob won"t clear that will limit placement options.
I do have a question about using though. It seems that once hollowing begins the outside of a form or bowl will soon distort, either due to internal stressors being released, or moisture loss. So what do you do about that? It would seem that before too long the form will be bouncing around on the wheels as it changes shape. Thanks for sharing your insight on this.