Shaft Coupler
This aluminum coupling connects the Z-axis stepper motor to the leadscrew to allow FarmBot to move in the Z direction.
Specs
| material | Aluminum |
| length | 25mm |
| outer diameter | 20mm |
| inner diameters | 5mm and 8mm |
| screw material | Stainless steel |
| screw drive size | 2mm hex |
| Price | $6.00 |
| Quantity |
Express - 1
Express XL - 1 |
| Purchase | The FarmBot Shop |
| internal part name | Shaft Coupler - 5mm to 8mm |
| cost | $1.85 |
| notes | v1.0 screws had 2.5mm drive instead of 2mm, requiring an extra allen key to be added to the kit. Screws must be stainless steel and have 2mm hex drive. |
Component tests
| Test | Description | Target | Tolerance |
|---|---|---|---|
| Inner diameters | Measure using digital calipers. | 5mm and 8mm | +/- 0.05mm |
| Motor shaft fit | Connect the coupling to a motor shaft. | The coupling should be easy to connect and resist pulling off by hand once tightened. | N/A |
| Leadscrew fit | Connect the coupling to a leadscrew. | The coupling should be easy to connect and resist pulling off by hand once tightened. | N/A |
| Outer diameter | Measure using digital calipers. | 18mm | +/- 0.5mm |
| Length | Measure using digital calipers. | 25mm | +/- 0.5mm |
| Screw drive size | Use a hex driver to validate the drive size of the screws. | 2mm | N/A |
| Material | Ensure the material is aluminum or stainless steel and will not rust by holding a magnet to the part. | Aluminum and stainless steel (no magnetic attraction) | Weak attraction to stainless steel is permissible. |