Pre-Prototype CNC Design
Chopper's Right & Left Legs are derived from Cleofett's .dwg drawing files.
|At first glance, Left and Right Legs look like they might require two different designs. The Legs, however, share a lot of details in common. The most obvious parts that are different are the top portion of the two legs and the detail attachments that mount on the front surfaces.|
|Here we've stripped away the leg struts & the detail attachments on the front surfaces. The light blue section above is common to both designs and is not structural. It will be assembled from .125 thick styrene as will the upper part of the Right Leg. Because of the complex curves, the upper part of the Left Leg will be a casting. The Detail parts of the Leg & the Leg Struts may also be fabricated as castings.|
Click on this image to bring up a 3D .pdf version
|What's left is the structural part of the
leg that's common to both legs. Here I'm using .188 thick styrene in a
design similar to the one I used for R2's Box Beam Legs.
In the rear of the leg there is a double layer of .188 around the
shoulder mount area. Because of the discontinuity in the rear of the
Leg around the Ankle there is a double layer of .188 in the front of
the leg. the two sections are bridged by a pair of box beams (only 1
rib is shown, the 4 sets of slots are where the box beams are located.)
The center channel between the two beams will be open for wiring to
descend from the shoulder down to the ankle and exit on either side of
the foot mount.|
What's still to be done: I need to account for a layer of .040 to cover the edges of the lower part of the Leg and two layers of .040 on the upper, curved portion. There will also be a layer of 040 on the rear of the leg to cover the rib slots that are covered in the front by the blue detail piece.
Please ask questions, make comments & suggestions that you think might improve the design. I'm looking for clever ways to mount the removable shoulder hubs as well as the detail attachment for the Right Leg that overlaps the shoulder hub! Since I'm also designing a Frame for the body I'd appreciate any pointers to documentation and drawings of the shoulder mounting hole patterns that are being used.
Contact me using: fpirz (at) media (dash) conversions (dot) net
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