follow up on my tumbler motor question

[porthos]

referring to yesterdays overheating motor on my thumbler tumbler. i soaked it overnight in mineral spirits, dried well ,assembled and started up. after 1/2 hr its too hot to touch for more than a couple seconds. installed the new motor that i bought and it gets hot (lets call it very warm) but stays there. on a related note i made a oversize pully for the motor to increase the speed. the standard pully gives 22 rpms the oversize one gives 40 rpms. the down side is the oversize pully shuts down the motor after 5-8 minutes. now a question. is the motor stopping because i have the original belt too tight because of the bigger pully; or, because there is a bigger load on the motor???. i don't understand how there would be a bigger load on the motor

[tred1956]

Changing the pulley to a bigger drive pulley will increase the load on the motor. Just like changing the sprocket size on a bicycle makes it hard to pedal but also makes you go faster. I am sure some of the smarter members can explain it better.
Safe shooting
Doug

[jsizemore]

You splained it fine tred.

[runfiverun]

yep.

my tumbler runs small at the front and big at the rear.
this allows the motor to turn quicker but turns the small bar that turns the drum faster too.
the rpm that the drum turns is the final speed. [about 60 rpm]

I'm running about a 6-1 gear speed.
1/2" across where the belt is on the front drive and 3" where the belt goes on the rear drive.
the bigger rear is connected to the 1/2" bar that turns the drum.
a 3,000 rpm 1/30th hp rated motor turns it all and does about 4 lbs of brass 5 lbs of pins and 8 lbs of water no problem.
it turns the same amount of brass with dry media just as easily.

[mdi]

R5R, your tumbler sounds like my ex-wife; small in the front and large in the rear...

The extra load on the small motor from the larger pulley works the motor harder, increasing the heat, and the "thermal protection" fuse shuts it off. I'd check to see if there is adequate air movement around the motor (so it's not enclosed), or if a fan isn't working properly (many small motors like this have fans attached to the rotor shaft to aid cooling; heat is the worst enemy of electric motors). I'd go back to the original pulley, make sure air flow is unimpeded (drill vent holes in the housing if needed), and don't overload the tumbler...

[Alstep]

Might better belt up a treadmill to the tumbler and let the wife run it. That way she looses weight & gets into shape, and your brass gets cleaned. Win-Win situation!

[edp2k]

point a fan at the motor while it is running.
if you don't have one, check out garage sales or thrift stores and pick one up for a few bucks.

would also go back to the original pulleys as they wont put such a big load on the motor and
the motor will last longer. although now that you have a spare you could run one at the high speed
and then swap in the other motor when first one dies :)