I need to get one of those, not so much for bars, but they do seem handy for that and other things. For my light bar dressing needs I just use a file and try and hold it square.Vertical belt sanders do it quick and square.
Double posted by accident, trying to delete.Vertical belt sanders do it quick and square.
If you were asking me, I used different pulleys to slow it down. Small pulley on the motor and large on the arbor. The sanding disc is a steel plate made for it with a self-adhesive disc stuck to it.You have a controller inline on your power cord? What kind of sanding disk do you put on it?