Re: CIM's Over loaded/Heated
 

actually the heat pipe is clamped inside two aluminum plates, which have better surface contact with the CIM. we were considering getting some thermal paste to improve the heat conduction, but it is not that much of a problem for us, mostly a clever gimmick. however 1024 has a better approach, you could try something similar with whatever methods available.

Re: CIM's Over loaded/Heated
 

the way you are describing the set up your cim has a torque of about 19 Nm and is stalling where the fischer price (in the stock gear box?) with torque of about 12 Nm is not. this means that you have a bad CIM or something in your system is not allowing free rotation. A bad bearing? too tight belt system? chain and cim misaligned?

Re: CIM's Over loaded/Heated
 

How'd you do that? If you used a Victor/Jaguar to drive the motor with a small fraction of normal power, that can cause heating. CIMs run best at full voltage, you then mechanically reduce their speed.

Re: CIM's Over loaded/Heated
 

I will get a picture up soon, this weekend just using fans between matches, we cooled the CIMS down enough, however for the championship we are going to need to develop a heat fin. The current set up starts at the CIM with a sprocket on it, that leads by chain to a larger sprocket. Than attached to the large sprocket is a large pulley, from there a belt connects to our wheels. Can you side load CIM's to an unhealthy extent? Thanks
Matt

Re: CIM's Over loaded/Heated
 

Last year we were using a single CIM to winch cable through a bunch of pulleys to winch our arm / claw to score track balls. The motor was getting extremely hot, so we zip tied 2 of the small fans that come in the kit of parts to the motor, and it was cool all the time after that. A small ammount of airflow can make a big difference. If you have a little bit of extra weight, this should take care of your problem.

Re: CIM's Over loaded/Heated
 

Are you using the gearbox from a drill for traction control?

Re: CIM's Over loaded/Heated
 

Does the belt system spin easily if the CIM is removed. Because if the system is putting up large amounts of resistance, something most likely needs to be greased or loosened.

Re: CIM's Over loaded/Heated
 

Ok,
I am going out on a limb here. From your description, you are not tripping breakers so that means you are likely running about 40-50 amps under load. Assuming a nearly fully charged battery, you are dissipating up to about 500 watts in the motor if you are at full throttle. Certainly something over 400 watts. You say the motors get hot after a long period of operation so the 40 amps for 15 minutes still seems about right. We can only guess here, but I think that if you checked the motor curves in the First docs, you will see that you are far from efficient operation.
That being said, the cooling tips given so far ony really make you feel better, they do not prevent over temp damage to the motor windings. The only thermal connection in the CIM motor is through the two bearing surfaces at either end, to the armature. The heat you feel by touching the case is a mere fraction of the heat at the core of the armature. There is no way to get the heat out of the CIM armature (that part where all the wiring is at). There are no cooling holes (and none allowed), there is no internal fan and no temperature exchange except for the convection cooling of the internal parts coupling to the magnets. My suggestion is to fix this ASAP and replace with new motors. It sounds as if the motors are damaged. That means some failure in the future. Be proactive and get the plan together to prevent an issue at your next event.