Let's Make Robots!

What can I get away with in bearings?

I'm in the process of building up a drive system from scratch around a couple of high-torque NEMA 17 steppers.  The idea was to use a small V-Belt drive to provide a boost in torque so I could use larger wheels and get up off the floor a bit.  I have a 4:1 reduction going with an intermediate pully in addion to the drive and wheel pulleys.  I'm machining all the parts myself and have the pulleys made.  I wanted the ends of the wheel and intermeadiate pulley to hang free.  Looking at bearings it's become clear that even cheap ones if doubled up on the fixed end of ea