FIGURE 3. Ti axle
using a die to thread.
FIGURE 5. Drilling
out the pulley.
FIGURE 4. Ti axle threaded with nut.
FIGURE 6. Machining
off the hub.
that 3 mm pitch HTD x 6 mm wide
belts work well in Beetle class bots.
A good source for pulleys and belts
is www.sdp-si.com. You can also
get custom pulleys from
On the original version of Weta,
I used a 40 tooth pulley. I have since
moved to the 30 tooth shown in the
downloadable drawings from the
FIGURE 7. Pulley and
flange on bearing.
FIGURE 8. Pulley
on beater bar.
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