Some Rotozip bits are longer than any of the Dremel bits at Lowes. The tool is a Chicago cable driven rotary tool with a small conventional chuck -- it cannot open wide enough for a 3/16" drill.
Flexible Shaft Grinder and Carver
I'm going to use the bits I have -- I noticed after cutting the sheet that the gantry wingnuts had loosened and this could explain some of the drift I was seeing. I'm learning what to stay on top of...