Holy Cow - Mat cutting

Oh, my! I decided to cut my own mats. I think I've got it now, but I cut 5 mats before I got one photo framed tonite. It was a double mat, so not too bad; but I thought I had all the technique and measurements right. When I got the blade down far enough, I had calculated the inner mat wrong. Well, I'm glad to have it done and know I can do it. I'm using Logan equipment - free standing cutters and ruler. Precision is good - the cutter's that is!