|When considering building a machine to
wave wind coils there are two important aspects. One, you
need a heart shaped cam plotted to ensure a linear
reciprocal motion. Two, you need a very close ratio
retard drive between the spool and the feed arm. The
second aspect was the most difficult because I could not
obtain gears with the very close ratio required. The
problem was overcome by making pulley wheels out of SRBF
material. After initial cutting out they were turned
using my bench drill and a file. The one on the handle
shaft is 34mm dia. and the one on the winding spindle is
34.8mm. The heart shaped cam was plotted using Microsoft
Excel but can be done equally well on paper. Below are
five close up photos of the mechanism.
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