SERVO 01.2014 47
The first change in the design is the wheels.
While you can make the tires shown in last month’s
article, the new components shown in Figure 1 will
add some construction options.
The new construction is a little different than
what was shown last month. You assemble the main
hub using four #4-40 x 3/4” machine screws and lock
nuts as shown in Figures 2A and 2B. The 3D printed
hub is a single part, but still needs the screws. The
screws are also used to hold an inner support hub
which will be installed later. When assembling the
laser cut gears, you need to make sure the teeth are
Figure 3 shows the laser cut tires. They can be
stacked in many configurations. You can use a single
tire or up to three on each wheel.
Figure 2A. Figure 2B.