Many of the construction techniques used in
Poundcake were similar to those used in Cupcake.
First step: cut
some side plates out of 1/8" aluminum and put in bearings
for wheels. The holes in the center were supposed to
be for the intermediate shaft, but I ended up not using
them.
Front and rear pieces,
along with some axles. It is starting to look like a
bot.
Internal bulkheads cut
out of 1/8 polycarb. The drive motors are mounted as a
quick test.
The bottom plate is
made from .03" carbon fiber, and is attached with 26 2-56
machine screws. Quite a lot of work to drill and tap
all of that, but it should be sturdy.
The tiny skinny drum,
cut from a piece of 2" aluminum pipe. The teeth are
made from 1/8" keystock and held on with 4 2-56 bolts.
I cut small grooves in the pipe to help hold the teeth on.
With end caps attached.
The end caps were cut from 1/8" delrin and have bearings
pressed into them.
One end cap with a 30
tooth MXL pulley carefully attached.
The finished drumette.
Total weight of the drumette is about 80 grams. That
might have to be cut down as the bot is looking like it will
be overweight.
The frame with the
weapon motor installed.
And the frame with the
pieces that will hold the drumette's axle.
An illustration of the
drive system Hopefully isolating the Copal motors from
the drive wheels with plastic servo chain will give the
system a little bit of "give", which will make life easier
for the somewhat fragile gearboxes in the 30:1 copals.
