When building your ShapeOko CNC machine, it is important to have all the necessary components to ensure smooth operation. One crucial component is the drive shaft bearing/bushing. This bearing allows the drive shaft to rotate smoothly, transferring power from the motor to the cutting tool.
To ensure the best possible performance, it is important to choose a high-quality bearing. One option is the Ruland PSMR16-5-5-A Set Screw Beam Coupling, made of polished aluminum. The metric size fits a 5mm bore A diameter and 5mm bore B diameter, with a 15.9mm OD and 20.3mm length. This coupling has a nominal torque of 1.36 Nm and can be purchased from Chinese supplier bluestone002 on eBay for $2.99 plus $1.56 shipping and handling.
To connect the bearing to the motor, you will need a 5mm-1/4" coupler, as well as motor mount spacers. These spacers will help stand the motor off the plate to make room for the coupler (and possibly pulley). You can find spacers made of aluminum or other metals, or even nylon, at a hardware store like DIY or Inventables.
For the idler pulleys, you will need idler spacers to act as standoffs on the motor side to account for the extra space used by the couplers. This can include 2 1/2 inch spacers or a stack of washers. You can also use 2 1/4" nylon spacers, as well as #10 5/16" 1/4" spacers and M5 washers. Alternatively, using 10 1/4" spacers (2 per axis for idler wheels, 4 for Z-axis V-wheels) would be ideal.
To secure all these components, you will need various bolts, screws, and washers. For the motor mount, 4 M3 45mm capscrews are best, though some have used brass circuit board standoffs. You may also need 4 M3 50mm screws (padded with washers) and 4 M3 60mm SCH screws (purchased from Home Depot). M5 nuts will also be necessary.
It is crucial to have all the right components when constructing your ShapeOko CNC machine. With the right drive shaft bearing/bushing, couplers, spacers, and hardware, you can ensure optimal performance and smooth operation.