Dc motors and temperature

[StarryNight]

Just putting the finishing touches on my new winder and not having worked with dc motors before I've notice that after running for 15 minutes or so the motor and shaft becomes quite warm. I'd like to ask how hot do these motors usually get and do they break down due to over heating? The PWM and switches are nice and cool. The motor becomes hot to the touch but not so much that it is unbearable. I could make a cut out for a computer fan if needed.

Edit: at 10 minutes running with nothing attached to the shaft the motor casing reads 90F or 32C (no ventilation in the box)

[Joe Gwinn]

Just putting the finishing touches on my new winder and not having worked with dc motors before I've notice that after running for 15 minutes or so the motor and shaft becomes quite warm. I'd like to ask how hot do these motors usually get and do they break down due to over heating? The PWM and switches are nice and cool. The motor becomes hot to the touch but not so much that it is unbearable. I could make a cut out for a computer fan if needed.

Edit: at 10 minutes running with nothing attached to the shaft the motor casing reads 90F or 32C (no ventilation in the box)

Won't hurt anything so long as you can comfortably hold the motor in your hand. The fan is a good idea for long-term and/or heavy use.

[David King]

I'd just set up a convection (air) current around the motor by drilling some holes in the top and bottom of your enclosure.