High torque, low RPM, low amperage 12v DC motor for a Solar powered trommel

Gelmac

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Apr 30, 2012
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I am looking for a high torque, low RPM, low amperage 12v or 24v DC motor for a Solar powered trommel/sluice combo build. The trommel is 11" diam the length is over 21". I want to make it light weight and portable.
I am planning to drive the trommel using sun energy.

There is a solar products dealer nearby so I can get any type of solar products easily .

This is my source for solar panels: Solar Kits | BBOXX .

They have solar kits, one is 17Ah Battery- 50W Solar Panel (foldable) that is also capable of powering AC devices (max 120W) using an external inverter, there is also higher end models (that contains an in-built inverter): 38Ah Battery- 120W Solar Panel / and the biggest one is : 120Ah Battery- 185W Solar Panel

The Batteries are Maintenance Free AGM Type , Sealed Lead Acid type.

The pumps I intend to use are 2 tsunami 1200 gph bilge pumps, each draws 3.5 amps.

The type of material I want to run through this system , is mainly tailings of hard rock mines, there is no rocks or large sized gravel in those tailings only ground ore, much like fine sand.

Also using a wind shield wiper motor , requires gear reduction, and I prefer not to go to that route unless I had to.

What is your recommendation on this setup. I 've searched a lot on the net, but can't decide what to use.

Please any advice on these will be appreciated
 

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.....a high torque, low RPM, low amperage 12v or 24v DC motor...

I believe that high torque and low amperage are somewhat mutually exclusive
terms, as it generally takes more amperage to power any high torque motor. Gear
reduction will almost be a must, I'm afraid, but if you get the right ratios you
might be able to turn that trommel with a load of aggregate in it.

This is a great place to look for all kinds of equipment, and they're surplus
motors are generally priced very reasonably. Surplus Center - Hydraulics, Engines, Electrical and More

Have you looked at any of the DC servo motors? Not sure how much torque you need,
but maybe you can find one that will work with the amount of amperage you can supply?
Stepper motor controllers can get a bit spendy, but it might be a solution?
 

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That's a tough choice because its hard to gauge how much torque you would need with a shovel full of rocks in the trommel. And us mere mortals don't have an easy way to measure it. You might try several motors before you get it right.

What if you picked a motor / gearbox that you think would work.
Get the amps it draws and figure out how big a battery you would need to run it all day. It'll be bigger than you think.

Then pick a solar panel that could charge that battery in a day. It'll be bigger than you think.
Charge one battery while using the other.

That 17 AH battery with the 50W panel-- the battery would probably last all day (surely you won't need to draw more than an amp) the panel is going to give you about 4 amps charge current. Lets see, 4 amps times 8 hours of sunlight == 32 AH, enough to charge the battery.

Your mileage may vary, no warranties expressed or implied.
 

Might try a window regulator motor. Although I doubt it would last long. I think a wiper motor would be more durable...

Sent from my SCH-R930 using Tapatalk 2
 

Find the motor off of the wheel chair lifts you see on vans.
I had 2 of them at one time and cant find them now to give you any specs.
But think about it,a 150 to 200 lb person,plus the chair.It has to be high torque,and low voltage or it would kill the battery picking up the person.
There are usually 2 of them,1 on each side.
 

736763621_260.jpg

[edit]This one uses the motor and gearbox from one of those powerwheel kids vehicles

 

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Thanks a lot to all of you for giving such diverse and invaluable suggestions :thumbsup:

I think I will try the Windshield wiper motor with gear reduction (though I am not comfortable with this choice) mainly because I have couple of these laying around waiting to be put into some good use ;)

Thanks jcazgoldchaser for the suggestion, I found a used 12v rechargeable Dewalt drill, ,truly would fit the build as it has already speed control (low-high), but the price wasn't right for me, so I dropped this option.

I am waiting for the Solar kit Supplier's Engineer reply for the right module to use with the trommel motor and bilge pump setup.

Cheers to all of ya, stay safe out there.
 

Just my two cents, but from working in the automotive industry I am not sure that a wiper motor will provide the torque you are looking for. The wiper tranmission is not a heavy piece to actuate and while the motor itself is used for long duration and will give the durability you require, I am not so sure it will take the torque load you are looking to move. (If you live in snow country and have ever worked in a parts store you would know how many wiper motors sell from people not clearing the windshield).

The previous suggestion of a window lift motor would probably suit you better. If it were me, I would pick one from the drivers side front of a big car (or truck) with a nice heavy window. The front left motors are heavier duty as they are the most used window of a vehicle and the manufacturers are aware of that fact.

Good luck!
 

Thanks jcazgoldchaser for the suggestion, I found a used 12v rechargeable Dewalt drill, ,truly would fit the build as it has already speed control (low-high), but the price wasn't right for me, so I dropped this option.
The thrift stores here have drills all day long under $10. I even saw them still on the shelf yesterday afternoon and that was 1/2 off day. When I looked for wiper motors online, they were over $20 and a speed control was extra ($10 aliexpress).
 

Hi (soxfan401) that's sounds good to me I can get that kind of motor. Thanks for the tip.

Thanks jcazgoldchaser. I reside in Africa so these motors are not manufactured locally they are imported , so their prices is high than that in your place
-due to custom fees ...etc- . Buying a second hand Wiper motor is cheaper here than the used Battery powered drills. Because these are used in metal workshops they are considered commercial (business like) items not for home DIY'er's . So even a used drill would be double the price of a wiper motor.

On a side note what is best for RPM reduction of the motors , I see many trommel builders use large sprockets and chains yet others prefer a pulley (flywheel) with v-belt, what's the pros and cons of using either of these ?
 

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I am looking for a high torque, low RPM, low amperage 12v or 24v DC motor for a Solar powered trommel/sluice combo build. The trommel is 11" diam the length is over 21". I want to make it light weight and portable.
I am planning to drive the trommel using sun energy.

There is a solar products dealer nearby so I can get any type of solar products easily .

This is my source for solar panels: Solar Kits | BBOXX .

They have solar kits, one is 17Ah Battery- 50W Solar Panel (foldable) that is also capable of powering AC devices (max 120W) using an external inverter, there is also higher end models (that contains an in-built inverter): 38Ah Battery- 120W Solar Panel / and the biggest one is : 120Ah Battery- 185W Solar Panel

The Batteries are Maintenance Free AGM Type , Sealed Lead Acid type.

The pumps I intend to use are 2 tsunami 1200 gph bilge pumps, each draws 3.5 amps.

The type of material I want to run through this system , is mainly tailings of hard rock mines, there is no rocks or large sized gravel in those tailings only ground ore, much like fine sand.

Also using a wind shield wiper motor , requires gear reduction, and I prefer not to go to that route unless I had to.

What is your recommendation on this setup. I 've searched a lot on the net, but can't decide what to use.

Please any advice on these will be appreciated


Amazon.com: 12v high torque dc motor gear
 

Hey Doitlaynstyle, thanks for the good find :hello2: those are affordable and with the right RPM ,

I found similar to those before but are they effective for tough work load ? pardon my suspicion , but which one is better at that page , I would rather tend to choose the (190 Rpm 12Vdc Right Angle Drive Electric Motor From Car Seats) one, but what about the others, are they reliable?
 

Hey Doitlaynstyle, thanks for the good find :hello2: those are affordable and with the right RPM ,

I found similar to those before but are they effective for tough work load ? pardon my suspicion , but which one is better at that page , I would rather tend to choose the (190 Rpm 12Vdc Right Angle Drive Electric Motor From Car Seats) one, but what about the others, are they reliable?

I have no experience with any of them but Amazon has always been good to me about faulty products. Also if you have a failure you're only out 12 bucks. Good luck. Keep posting in this thread as you build. I'm curious to see how it works out for you. I build my own solar panels but I don't see doing dollar prospecting lol. Good luck!

My RV is off grid'ish this year and should be fully off grid next yr.

 

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Yep can't beat that price lol . Sent to the manufactrer of the Solar kit for advice on the suitable kit they are selling for this project , waiting for their reply. Building stuff is my hobby also but the challenges some times slows things down a bit. Yes will continue on posting about my progress.
 

Ford Bronco rear window drive motor with a heavy duty speed control switch. Chain drive- noisy, lots of wear in a gritty sandy environment. V belt pros-cost effective, easily adjustable with a variable speed drive pulley. Good wear. Cons- possible slippage but probably not a big problem with your application. Cogged belt- too expensive no real advantage other then no slippage issues.
 

Yes, had noticed the slippage issue on many machines , easily fixed with some adjustments of position of screw/pulley. Thanks for your comment.
 

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