Hi everyone,
Longtime lurker, first time poster.
Yes, we've obtained quite a few of these motors and had previously been hired to solve a problem with some of them that resulted in the magnets departing the rotor and the stainless bands failing to restrain them. As Methods described, the forces are huge once you get past 5,000 rpm. The carbon wraps worked and Ryan tested them to failure. But they worked out the problem with the motor manufacturer so we didn't get that rework job. But we ended up with this salvage job and so far, it's showing a lot of promise. We found the root causes of the failures and have refined the rework technique. Methods has been helping us setup the test rigs and trained us on how to safely run them. We've now got a few carbon wrapped motors that have passed the basic tests and now need some field testing. We'd like to offer either the 75-5 or 75-7 for $500 to qualified testers. If they are controlled to run no more than 6,000 rpm and stay under 120C, and they fail, we'll replace it.
Note these are new motors that have been tested to 6150 rpm and kept under 120C. We're balancing the rotors. The carbon wraps result in 55 grams lower weight on the outer surface of the rotor. That may not sound like a lot but it's exactly where you'd want to lose mass.
We have 2D drawings and solidworks models of the motors if needed.
Who's in?
Craig