Need RS-550s ASAP

[Jared Russell]

Originally Posted by David Guzman

While the stall torque is close between RS-550 and FP, the free rpm is 15600 for the FP and 19300 for the RS-550. After they go on the 256:1 planetary the output difference is rather large. However this is still my back up plan but I hope I can find the RS-550s.

It sounds like you are looking for a motor/gearbox combination that gives you ~75RPM theoretical free speed @ ~127 N*m theoretical torque (these are the numbers of an RS-550 reduced by 256).

A CIM at 64:1 gives you more speed (~83 RPM before losses) with more torque (~155 N*m stall). BaneBots sells a 64:1 CIM gearbox: http://banebots.com/pc/P80K-nnnn-0005/P80K-444-0005

Of course, this is a more expensive (and much larger) option, but it would give you the specs you desire.