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FIRST Global Building Guide Created by REV Robotics 2019, Licensed Under CC BY-SA
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Figure 44: Shaft Collar with Standard M3 Hex Cap Fastener
Spacers for the 15mm building system have a 5mm hex center, are made of Delrin, and come in 3 lengths (Table 5).
Spacers are used between parts on a shaft to take up the extra space and prevent the parts from sliding on the shaft. If
more than a few spacers are needed, it is typically better to use a shaft collar.
Table 5: Spacers
1.5mm Spacers
REV-41-1325
3mm Spacers
REV-41-1324
15mm Spacers
REV-41-1323
Spacers and shaft collars are used for the same purpose: to constrain components on a shaft. This keeps shafts from
falling out and also keeps motion components, such as gears and sprockets, aligned. For larger sections of exposed
shaft, shaft collars are preferred because installing multiple spacers is less efficient and is more difficult to manage
during robot building and maintenance. For shorter shaft lengths, spacers are generally more efficient (Figure 45).
Figure 45: Shaft Collar and Spacer Side by Side