AC or DC

[Krokodil]

Hi guys, I'm planning to build a rotary type tumbler for my brass cases.

The setup will consist of two parallel shafts on bearings with a PVC pipe as a mill rotating on top of the two pipes. One of the shafts will be driven by a motor.

I'm however unsure about the power supply. A DC motor like a windscreen wiper motor and power supply would already have the correct rpm and I don't need to do gearing.

A AC motor would require gearing to get the rpm down to approx 60-100. This type of motor just feels more industrial to me.

The costs of AC vs DC + power supply would be about the same.

Any advice?

 

[Gary S]

If the DC motor has rpm better suited to your needs, I'd go with DC. I don't see a brass tumbler getting heavy use 24 hours a day, 7 days a week, so any motor should be OK. I assume you have AC in your walls like in the US, and if so, you would need a DC power supply which should be readily available.

 

[Krokodil]

Jip, we also have ac from the wall sockets.

I don't particularly like dc motors, but the gearing benefit might be worth it.

Thanks

 

[sberry]

If the cost is the same why screw with the additional rigging when a guy could plug directly in to the wall without conversion and get the same thing?

 

[HoosierBuddy]

Dumb question: Do you need speed control?

Phil

 

[Krokodil]

Phil, I don't need speed control. I'll set the speed with pulleys or sprockets and run at a constant speed.

 

[HoosierBuddy]

Phil, I don't need speed control. I'll set the speed with pulleys or sprockets and run at a constant speed.

Then I would recommend an AC motor.

Phil

 

[Krokodil]

That is my thinking as well. It seems that generally ac motors have more options wrt mountings, shafts, etc.

 

[Milton Shaw]

A/C motors generally don't have brushes to wear out, where most D/C motors have a limited life due to brushes. Look and see if you can find any lapidary tumblers they would do the job and already set up for slow tumbling and long run times. Might try wanted to buy listing on C-list if you have that there.

 

[kbs2244]

Wiper motors are considered a “safety part.”
They are held to a much higher quality control and lifetime standard.
If you can mount it easily I would go with it and an old car battery.
Even a badly used battery should give you a years worth of energy.

 

[Krokodil]

Wiper motors are considered a “safety part.”
They are held to a much higher quality control and lifetime standard.
If you can mount it easily I would go with it and an old car battery.
Even a badly used battery should give you a years worth of energy.

Would you recommend running it on permanent charge under load or charging up and then running the application?

 

[mrb]

you can run a wiper motor off a computer power supply. To use an old PC power supply jumper the green wire to black to make it turn on, and take 4 or 5 yellows and 4 or 5 blacks (check on the PCB inside the supply that the yellows you choose all go to the same place) yellow is 12v black is gnd.

 

[kbs2244]

I would just hook it to the battery and use it until it stopped.

I have a power window motor hooked to an up and down chain for my drill press table.
I was going to do all kinds of things to keep it charged but never got arround to it.

After 2/ 1/2 years, when it slowed down, I put a trickle chager on it over night.
That was 3 years ago.