This small ball caster uses a 3/8″ diameter metal ball. The height of the assembled kit ranges from 0.4″ to 0.6″, depending on the combination of included spacers used.
Overview
This ball caster kit includes a black ABS housing, a 3/8″ diameter metal ball, two spacers (1/16″ and 1/8″ thick), and two 7/16″ #2 screws and nuts. The total height of the ball caster, 0.4″, can be increased to about 0.6″ using the included spacers. The two included #2 screws can be used to mount the ball caster to your chassis, or you can use your own #2 or M2 screws if your application requires a different length.
Note that our ball casters are designed for small robots; they are not intended to bear more than a few pounds. With more weight than this, friction between the ball and the housing will generally keep it from rolling well.
For detailed dimensions, see the dimension diagram (164k pdf).
Comparison of Pololu ball casters
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| Pololu ball casters with plastic and metal balls. Ball diameter from left to right: 1″, 3/4″, 1/2″, and 3/8″. |
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Pololu ball caster
ball diameter |
height with
no spacers |
distance
between screw holes |
weight with
no spacers or screws |
| 0.40″ | 0.53″ | 0.03 oz | |
| 0.40″ | 0.53″ | 0.14 oz | |
| 0.53″ | 0.58″ | 0.07 oz | |
| 0.53″ | 0.58″ | 0.32 oz | |
| 0.88″ | 0.24″ | 0.25 oz | |
| 0.82″ | 0.61″ | 1.05 oz | |
| 1.10″ | 0.48″ | 0.65 oz | |
| 1.10″ | 0.48″ | 0.58 oz | |
| 1.10″ | 0.70″ | 0.36 oz |
Dimensions
| Ball diameter: | 0.375 in |
|---|---|
| Weight: | 4 g1 |
General specifications
| Ball material: | metal |
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Notes:
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| Pololu ball caster with 3/8″ metal ball. |
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| Pololu ball caster with 3/8″ metal ball with included hardware. |
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File downloads
- Dimension diagram of the Pololu Ball Caster with 3/8″ Ball (164k pdf)
- 3D model of the Pololu Ball Caster with 3/8″ Ball (2MB step)
- How much weight can Pololu ball caster support?
- Our ball casters are designed for small robots; they are not intended to bear more than a few pounds. With more weight than this, friction between the ball and the housing will probably keep it from rolling well.



























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