I need electrical help with a rock tumbler issue please (not RC related)

[Velodromed]

My other hobby is rock tumbling and jewlery making. I recently picked up this super cheap rock tumbler (for tumbling rocks) figuring I’d swap in a new motor when the stock one died, which looks like a brushed 540. It died, so I swapped in a motor off an old voltage, a brushed 550. It wouldn’t work much at all so I tried another 550 motor. No luck, it’s getting power but acts feeble and won’t turn the rollers. So I’m asking here since my electrical skills are rudimentary at best…what am I doing wrong?

 

[john 8s]

Don’t know anything about it, but it looks like an interesting hobby. Good luck with your issue.

 

[Velodromed]

Don’t know anything about it, but it looks like an interesting hobby. Good luck with your issue.

It is. Discovered it a couple years ago and seriously got into it last year.
Thread 'Rock tumbling and jewelry making (Not RC related)'
https://www.arrmaforum.com/threads/rock-tumbling-and-jewelry-making-not-rc-related.56772/

 

[Jchammbone]

If you have a multimeter check voltage ....going into the motor... is it AC voltage? Maybe the "new" motor only runs on DC voltage...
Is the motor known to work before you put it in...?

Maybe your not getting enough juice to turn the armature..

 

[john 8s]

I will check it out.

 

[Velodromed]

If you have a multimeter check voltage ....going into the motor... is it AC voltage? Maybe the "new" motor only runs on DC voltage...
Is the motor known to work before you put it in...?

Maybe your not getting enough juice to turn the armature..

Thanks man. I am thinking it’s not getting enough juice also based on how the motors acting. I do not have a multimeter unfortunately and I wouldn’t quite know how to read one yet (I’m getting there slowly). It has a power supply that converts AC to 12v DC. That is directed to a circuit board, which I think reduces the voltage even more. I was just thinking, can I bypass the circuit board and connect the wires that lead from the 12v DC power supply plug, directly to the DC, 550 brushed motor?

 

[Jchammbone]

You can try that .... maybe there is something wrong with that control board.
It varies the speed of the tumbler/ motor?

 

[jkflow]

What's the brand name of the tumbler?
Motor kind of looks like the one in the video below, seems to be 12VDC. You can check it out by just connecting to a battery.
3S Lipo would work just fine for a test. See if either motor runs. If the new one runs fine, there is something wrong with your control board. Very possible that your old motor damaged those electronics by shorting out or whatever killed it. Also possible that your old motor is just fine.

 

[Johnny b]

Both those motors may have been manufactured the same year I was born. Time for a new motor.

 

[Velodromed]

You can try that .... maybe there is something wrong with that control board.
It varies the speed of the tumbler/ motor?

Yup. It’s a junk tumbler I got to experiment with. The only thing good about it is the barrel really. I have several other good ones I have running 24/7, including a 17 pound behemoth.
I tried hooking it up straight to the power wire and it would run for a second, then stop. So I need to get a multimeter and learn how to use it. It’s time for me to learn more. Thanks man, appreciate it.

What's the brand name of the tumbler?
Motor kind of looks like the one in the video below, seems to be 12VDC. You can check it out by just connecting to a battery.
3S Lipo would work just fine for a test. See if either motor runs. If the new one runs fine, there is something wrong with your control board. Very possible that your old motor damaged those electronics by shorting out or whatever killed it. Also possible that your old motor is just fine.

It’s an off brand with a 540 DC motor and has a power supply that converts it to 12 V DC. I hooked the new motors (ones I had previously used in the 2wd Voltage so know they work) straight to the power wire, bypassing the circuitboard, and the motors would run for a second then stop. I tried it out with two separate 550 motors with the same result.
It’s time for me to learn more about electronics anyway. I have learned so much from this hobby already. So I’ll keep toying with this thing and try to figure it out eventually. Thanks for trying to help me buddy!
You know what, I think I will test of the original motor further. I kind of just assumed it had gone bad when it stopped working. Because if it works off a 9V battery… Sometimes I have to go back to step one to figure out step two.

You can try that .... maybe there is something wrong with that control board.
It varies the speed of the tumbler/ motor?

Yup it was one of those 3 speed ones.

 

[Jchammbone]

Get motor, esc from a crawler rc setup (55t motor) radio battery of your choice... hook it up and you got speed controll and will be wireless.... use airplane radio since the sticks can hold position (i think) and you wont have to hold the trigger while it runs... lol


Hope you figure it out. Good luck!

 

[SrC]

My other hobby is rock tumbling and jewlery making. I recently picked up this super cheap rock tumbler (for tumbling rocks) figuring I’d swap in a new motor when the stock one died, which looks like a brushed 540. It died, so I swapped in a motor off an old voltage, a brushed 550. It wouldn’t work much at all so I tried another 550 motor. No luck, it’s getting power but acts feeble and won’t turn the rollers. So I’m asking here since my electrical skills are rudimentary at best…what am I doing wrong?

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If the Brushes are still usable in them, Spray them out well with an electrical contact spray. Focus on the Brushes and Commutator areas. What makes the motor finicky. And Place a drop of oil on each bushing. You might get some life out of them yet.
How many volts do they run at, in your tumbler?

 

[Velodromed]

If the Brushes are still usable in them, Spray them out well with an electrical contact spray. Focus on the Brushes and Commutator areas. What makes the motor finicky. And Place a drop of oil on each bushing. You might get some life out of them yet.
How many volts do they run at, in your tumbler?

This cheap one is 12v, and it’s a dc motor. And I did figure out that the motor is OK, it was a circuitboard that freight out. So I’m just gonna direct wire it to the power supply later today. I do need to go ahead and clean/relube the motor. Good point, thanks for the reminder man!

 

[SrC]

You know this stuff well anyway.

 

[Velodromed]

You know this stuff well anyway.

Starting to lol

 

[Velodromed]

You know this stuff well anyway.

As you suggested, I cleaned/lubed the motor and have even figured out how to wire it to where I got both the fan and the motor working directly off the power supply. I think the motors on its last legs though from certain noises and vibrations. So I need to learn how to pick out a proper motor for the application. I’m wondering if a 540 brushed 12 V DC, high turn (50+) rock crawler motor (as someone mentioned before) would work. Actually I need to shop RPMs not turns. Around 4000 RPMs and with high torque. I think.

Yup, much like a 3s car I’ll end up spending more on this than I did when I bought it (good thing I got it on sale for 30 bucks). But also much like a 3s car, I’m going to enjoy it the hell out of it once I get it working better then when new. I’m also learning a lot, so it’s worth it.

 

[Jchammbone]

Keep in mind on brushed motors for rc applications they usually only list them by turns...not sure about other applications. A 55t brushed runs about 1000 rpm per volt.. roughly... 12 v would come in about 12k rpms.
Probably why the circuit board... limit volts and also control rpms.
I think from my crawler days i saw a 90t motor.... maybe if you could find one similar might come in about 1/2 that rpm...5-6000 rpms. But i don't know for sure.

 

[Velodromed]

Keep in mind on brushed motors for rc applications they usually only list them by turns...not sure about other applications. A 55t brushed runs about 1000 rpm per volt.. roughly... 12 v would come in about 12k rpms.
Probably why the circuit board... limit volts and also control rpms.
I think from my crawler days i saw a 90t motor.... maybe if you could find one similar might come in about 1/2 that rpm...5-6000 rpms. But i don't know for sure.

That’s exactly what I’ve been pondering over this morning. Thank you for giving me a rough conversion, that’ll help.
I actually got it up and running. It’s too fast for polishing purposes though. Roughly 50 -60 RPMs right now. So it’ll work good for breaking down rough, fresh rocks. But not for polishing larger rocks, which is what I need. 18-20 RPM is best for that. But it works, so all good for now. I’ll continue my research and learning. As pointed out, I need to look for a brushed motor based on RPMs, not ‘turns’ so much, so that is what I’ll look for.

 

[SrC]

Buy some Cheap "rebuildable" open endbell motors of various winds, discussed above. Rebuildables tend to come in more various winds. Look to those. Then measure and compare their rpms using an RPM meter. You might get close to what you need. You can isolate and regulate the voltage somehow to that motor to dial it in better to polish at different RPMs.
Seems a simple RPM meter would help out. If you don't have one already?
You can do this.

BL motors are not judged by their RPM's. Longer Cans/Armatures also create more torque. 0540 vs 0550. (winds remaining same) The more slots it has the smoother the power band. The Lower the # of windings, the higher the Rpm's. And vice versa.

 

[Velodromed]

Buy some Cheap "rebuildable" open endbell motors of various winds, discussed above. Rebuildables tend to come in more various winds. Look to those. Then measure and compare their rpms using an RPM meter. You might get close to what you need. You can isolate and regulate the voltage somehow to that motor to dial it in better to polish at different RPMs.
Seems a simple RPM meter would help out. If you don't have one already?
You can do this.

BL motors are not judged by their RPM's. Longer Cans/Armatures also create more torque. 0540 vs 0550. (winds remaining same) The more slots it has the smoother the power band. The Lower the # of windings, the higher the Rpm's. And vice versa.

I don’t have one yet. I’ll look for a beginner one. Thanks for the further explanation, Steve!