building a trommel. Few questions

[roadrunner]

My barrel is going to be a water tank heater.
14 inches by 42 in long.
Am planning to use a 12 volt or 24 volt motor.
Has anyone heard or seen a wiper motor being used on one this big.
Or should I check for other stronger motors.
Going to use a flat belt.

 

[N-Lionberger]

I am curious about the same thing, I'm building a trommel from an old 16" inch water heater tank.

 

[roadrunner]

Well guess i will find out on my own.Pro
bably go with a 12 volt dc from ebay, this way i can see what the torque rating is, and the power draw.
Then use a flat belt, with an idler arm and spring for tension.
Just let the flat belt run on the barrel by itself.
With the idler pulley and motor pulley being grooved, or with sides on it,should keep the belt straight.
Got the top frame welded up today, and the legs cut.
Thanks for stopping by.

 

[Rockwerx]

Lots of guys have had success using a wiper motor. They make good torque and some have gear reduction which helps speed control.

 

[Jim in Idaho]

This particular gearmotor works very well on my jigs, and shaker table. RPM is about 180. Lots of torque. The unit slides onto a 12mm shaft diameter, and connects using a cotter pin. I usually use a 1/2" shaft with the end turned down to .472", or very slightly smaller. (12mm). I like to sandwich the output drive between bearings, or bushings, and let the motor float. Save wear and tear on the motor bushings.
Gearmotor Gear Motor 1 4 HP 180 Watt 12 Volt 170 180rpm Reversible | eBay
Jim

 

[roadrunner]

Thanks. Jim will go take a look.
Rock,yes I like the gear reduction

Jim shouldn't the trommel run at about 20 -30 rpms.

 

[Jim in Idaho]

Probably. The unit would have to be used with some belt reduction, and a PWM speed control, which is relatively cheap on Ebay($15.00+/-).
Jim

 

[roadrunner]

Jim, pwm same as light switch dimmer.
Of course i can afford the $15,

 

[Jim in Idaho]

PWM is "pulse width modulation". The speed is controlled by pulses of 12v. If you control the speed by lowering the voltage, you increase heat, and decrease torque...not good. By keeping the voltage at the rated max, and using pulses, of varying duration of that voltage, you don't lose much torque, and the motor doesn't overheat.
Jim

 

[roadrunner]

Ill ask here for the benefit of every one else. What would someone recommend as to the amps of the pwm.
I was thinking about a 30amp with a fuse included in the unit.
About 2000 to 3000 watts.

 

[Jim in Idaho]

30 amp would work fine. One thing i should mention is that few of these PWM speed controls from China have any protection from reverse polarity when connecting them to the battery.....be sure you get the polarity correct! DAMHIK...LOL
Jim

 

[roadrunner]

Yes, I was reading that in the description.
Also, I saw 1 or 2 that said they can not be used with a brush-less motor.
Any thoughts on that?
Just posted my first pic of it on my opening page.

 

[Jim in Idaho]

I don't know anything about the brushless motor applications. Will have to bone up on that.
Jim

 

[grazjsw]

Hi!
my old trommel is using 24v viper motor. 100 ah and 66 ah battery. the 66 ah went out of power after 9 days of trommeling. here is a link to my old trommel in action. So yes u can use it. im just bored to move batteries around. my new trommel uses 370w motor and it will run whit generator =).

 

[Jim in Idaho]

Yes, I was reading that in the description.
Also, I saw 1 or 2 that said they can not be used with a brush-less motor.
Any thoughts on that?
Just posted my first pic of it on my opening page.

The deal on the brushless DC motors is they use a solid state controller (built-in) to charge the appropriate coils as the rotor turns. Apparently, the PWM pulses aren't tolerated by the controller in the motor...it wants to see a constant voltage. In a brushed DC motor, the commutator determines which coils are charged, and when, as the rotor turns. The commutator is simply a mechanical switch, so the form of the voltage it sees is irrelevant.
Jim

 

[roadrunner]

Thanks for posting grazjw