I made the tape reading mechanism more reliable by weighting down the copper nails that serve as brushes. I also made a guide to prevent them from moving more than a half a millimetre or so out of position. This video shows the mechanism reading a card containing 24 4-bit words:
My next task is to make a 10-bit wide version of this. The card was made using a Silhouette Portrait cutter that I purchased specifically for this purpose using some of the prize money that I won for the Automation round of the 2016 Hackaday Prize.
Meanwhile I've been setting up X and Y axes. These axes should be capable of moving a felt tipped pen across some paper.