I also made one a year ago for cutting the holes out for the blast gates. I used a piece of 3/8 plywood. Not pretty, but very functional. I found I needed to put 3 screws through the cut out part to something underneath, and also anchor down the piece I was keeping to keep from ruining it when I got to the end of the cut. Jim,
Home of Irish Setter Rescue of North Texas
When Irish Eyes are smiling, they're usually up to something!!
At a minimum, I'm Pentatoxic...but most likely, I'm a Pentaholic. There seems to be no known cure. Pentatonix, winners of The Sing Off, season 3