Servo - June 2008

store. Since the ones provided are usually too short, I have accumulated boxes of these from McMaster-Carr in various lengths by doing this build on 1.5”, 2”, and 2.5” wheels in singles and doubles. Figure 2 shows the stack ready to assemble. In Figure 3, the hub screws and two washers are tightened to the point of deforming the plastic hub. The foam and plastic acts as “loc-tite” and I’ve never had them come loose.

Figure 4 shows one more important change. A mantra of combat builders is: “Set Screws Suck.” The miniscule allen head set screw in the Lynxmotion hubs MUST be replaced with a beefy cap head that can be cranked hard enough to

FIGURE 4

FIGURE 5

dimple the gearbox shaft. After losing several fights through slipping wheels, I came up with this method to ensure no more set screw related failures.

Finally, Figure 5 shows the whole assembly, along with a crudely manufactured bracket to hold the motor in place, and support the shaft at the gearbox output. SV