I'm working on a dyno design that uses an extra CIM from a previous years kit as the load. With it configured as a generator, varying the electrical load on the output will vary the load on the motor being tested. The motor shaft is mounted in a pillow block using a couple of rollerblade bearings (which just happen to be 8mm ID, and the shaft is 8mm OD), and a lever arm is attached to a scale to measure the resulting torque. I figure this will work OK on the smaller motors, I probably can't load the CIMs all the way up to stall with it, but I should be able to get enough points for a good curve.
I still have some work to finish up on the pillow block design, and I hope to get it all built this weekend. Now if I can just find the high-power electronic load we used to have at work, and a scale I can read with the PC, it should be fully automatic. I'll post an Inventor pic when I get it all designed.
Some days I sure miss having access to a motor lab
