"Don Foreman" wrote in message
...


The motor body has about 141 sq in of surface area. Each 1/2" high al
U-channel 10" long adds 20 sq in (four exposed fin sides)so, assuming
intimate thermal contact (not bloody likely!) you'd need 7 such
channels to double the effective area or halve the thermal resistance
to ambient. In fact, the "fins" won't be anywhere near that
efficient due to thermal drop across the interfaces. Some good thermal
compound between the channels and the motor could help considerably.

Increasing air velocity over the motor will very likely work a lot
better.

1/4 inch copper pipe, brazed to the outer case of the motor with chilled
water will keep the case cool - of course the armature will still overheat -
perhaps you could consider forced air cooling through the motor rather than
heat sinking the case?


** Posted from http://www.teranews.com **