Saturday, February 26, 2011

Finished Up Drivetrain Channel Work

Today I wrapped up work on the foot channels for the drivetrains on the outer feet.

I went over to my friend Kelvin's house to have the 1/4" holes that are used to attach the channel pieces to the main drivetrain bodies countersunk. The countersink bit I have won't reach that deep into the channel.

All four holes are ready to accommodate the 1/4" screws.

Back home, I worked on drilling the holes in the channel for the ankle bolts. First, I measured and marked the center point at the top of the channel.

Next, I measured 5/8" down from the top, and marked the spot to drill. The 5/8" measurement seems to work well for droid #1, so I'm using it again. It's high enough that the ankle bolt hole in the actual wooden ankle allows parts such as the ankle cylinders to clear the top of the foot shell, yet low enough that I can get a wrench into the footshell to tighten or loosen the ankle bolts without too much fuss.

Time to drill. I will be using a 1/2"->3/8" bushing for the 3/8" ankle bolt, but I decided to start drilling with a 1/4" drill bit, and follow-up with the 1/2" drill bit.

The 1/4" hole is done.

And the 1/2" hole is done as well. The bit self-centers in the hole with very light pressure on the drill press handle.

I pressed the bushings in place. Once these are installed on the droid and the ankle bolts are tightened down, they won't have anywhere to go.

Finally, I screwed down the channels to the main drivetrain body pieces. It can be tricky to get the nut to stay in place, so I used a thin strip of wood to support the nut under the hole.

This is probably as far as I'm going to take the drivetrains for now, until I decide to R/C droid #2. Still to be done is the locating and installation of the motor-mount bracket, but as I say, that will wait until I need it.

No comments: