Quote:
Originally Posted by Kos-Mos
I have seen cheap neodymium magnets losing magnetic field around 200-ish C... especially in cheap Chinese brushed motors (in RC cars). Once the process is started, it just goes exponential (motor has less torque, but the load stays the same, so more current has to flow, resulting in more heat and less torque...).
To feel the grip getting hot, the motor core would be close to 200-ish...
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Wow, crazy. The exponential rise in temperature is really interesting, kind of like a vicious cycle. In a sufficiently-large R/C car I could imagine there being a few options for introducing a cooling system. I can't quite imagine what we would need to cool an airsoft motor in-situ. A grip designed hand-in-hand with a motor housing, with the housing having a dense array of fins. The question becomes.. where to dump that heat?
I have noticed fairly huge differences in heat output from different neo motors which pretty much have the same magnetic stickiness and torque when tested "in the lab". My JG Blue hardly produces any heat at all, while at the same time the SHS High Torque seems to get fairly warm -- but only the long version, where as the short version doesn't produce much heat.
I've gotten the impression, but haven't been able to solidly verify, that some motors seem to produce less heat if they've powered by a larger battery with a higher C value. I'd love to hear someone explain why the heck that would happen.