If you just had a couple, I think I would just mark a line and freehand cut it with a skill saw especially if it could be caulked and painted. If there was very many to do or the cut needed to be more precise I would construct a cheater board to guide the skill saw. Another option is if the column doesn't have any cross grain trim it could be sent over a jointer to mill the back
I would like to learn how to use a chalk line with a circular saw. I tried it a time or two and the air from the saw blows the chalk away.
Last edited by Steve Neul; 06-08-2012 at 07:12 AM.