How do you cut perfect circles in wood? I'm trying with my jigsaw, and as you guessed it, I get less than perfect results. Just trying to make a new speaker baffle. I guess I could make a template, but then how would I make that circle? p.s. Birch ply seems to be warping my jigsaw blades, is that due to the glue? I guess I just need to go much slower. Thanks.