The encoder shaft would not be on the center shaft that the tape is wound around. So, it would not spin any faster as the tape was extended. The encoder shaft would be separate and have a sprocket that would fit into the holes on the tape. So as the tape leaves the case, it turns the sprocket and thus the encoder.
It is the way I would do it as optical has issues with getting dirty which is likely on a tape that is in a wood shop. -- Blue skies. Dan Rossi Carnegie Mellon University. E-Mail: [EMAIL PROTECTED] Tel: (412) 268-9081
