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Motor for hand cranked icecream machine Answered

He guys, i wanted to make my hand cranked iceream machine into a motorised one so would like to know what rpm and torque the motor should have.

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I think you could do a Tim Allen Tool Time thing and go down to Harbor Freight and get one of their gas powered Predator engines and hook that up. With enough RPM you could probably skip the ice cream part and go directly to a whipped frozen cream. Add some liquid nitrogen to the mix so it drops the mixing time and you could almost go comercial.

I would enjoy being "second banana" to Tim ;-)

I think I have a few electric ice cream machine (EICM) motors in my junk pile.

You want me to pull one out, and try to measure its speed and torque?

It might take a while to set up. The only thing I have for measuring rotating torque to is to build a drum with a rope wrapped around it, lifting a vertically suspended mass.

For measuring speed, well I have a clock, and I can count the number of times the shaft turns around. Actually I can tell you right now, the no load speed for a Rival(r) model 8401, is 40 revolutions per minute (RPM)

Also the plate on this motor says, (120 VAC, 1.2 A) which puts an upper limit on the electrical power input at, P = 120*1.2 = 144 watt = 144 W

And that can give us an upper limit on the torque. The mechanical output power cannot be greater than the electrical input power. But if I just set those numbers equal

P = (torque)*(speed) , torque = P/(speed)

torque = (144 W)/(4.19 rad/s) = 34.4 newton*meter = 34.4 N*m

But that's with the motor fully loaded, and with 100% mechanical efficiency. I am guessing the actual maximum torque (before the motor stalls, or overheats) will be maybe a quarter, maybe 10% of that number?

Actually I have no idea what the actual maximum torque will be, or what the slower, loaded, speed will be at that level of torque.

That's why it might be interesting to build the setup with the drum, with rope, lifting mass, to discover that.

It will need to be high torque, low RPM but I have reference for specific values. You could look up some existing old fashion motorized ice cream makers and see what they use or make a batch in the hand crank, count the rpm and if you can get a torque wrench on the input shaft you can measure the minimum torque for your motor.