I made very successful custom coder wheels by drawing them in AutoCad at 8 inches diameter and printed it with laser printer to onto white paper. I then took it to a photoshop with a copy camera and had them reduce it to about 0.75 inches in diameter. The reductions were then printed onto clear photo negative material. I was able to make small wheels that had as many as 30 bars / 30 spaces to get 30 PPR. Worked great.

Michael Karas