# small motor



## Sickie Ickie (Jun 20, 2006)

anyone know of a small motor, as small as a microwave motor or smaller, that can run for hours at a time without heating up?


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## The_Caretaker (Mar 6, 2007)

All motors heat up. What I think you are looking for is a small motor with enough tourqe to do what you want that doesn't pull a lot of amperage. What are you trying to do? How fast/slow RPMs? How much weight are you trying to move?


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## joker (Sep 25, 2007)

I'm not certain of the size of a microwave motor, but would a rotisserie motor work?


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## jabberwocky (Apr 30, 2008)

Record player.............


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## beelce (Jul 21, 2007)

Those little rotisserie motors have plenty of tourqe and can run for days....


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## Sickie Ickie (Jun 20, 2006)

Nada. Looking for a very small one that won't heat much because of it being next to cotton. I'm planning on using it for a FCG type stringed hand and fingers. The motor has to be small enough for a palm. The cotton or nylon is a glove that covers it. I don't want to risk the motor catching the glove on fire.


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## slightlymad (May 25, 2006)

Thats a tall order sickie and unfortunately I don't think you will find any thing but a (ugh curse st paty) you know a thingamgig. Any motor produces friction therefore heat. Sorry dude. but you could make a glove flame resistant.


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## beelce (Jul 21, 2007)

Sickie...just make a bigger hand


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## Otaku (Dec 3, 2004)

How about this:

http://www.allelectronics.com/make-...ANGLE-GEARHEAD-MOTOR-W/CONTROL-CIRCUIT/1.html

I have one of these - they're quiet and very small.


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## hedg12 (Jul 6, 2008)

Some servos can be modified for continuous rotation, and you can bypass the control circuit so that all you have to do is supply 5v to make it run. Don't know about duty cycle, but I doubt heat would be an issue.


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## Sickie Ickie (Jun 20, 2006)

Otaku said:


> How about this:
> 
> http://www.allelectronics.com/make-...ANGLE-GEARHEAD-MOTOR-W/CONTROL-CIRCUIT/1.html
> 
> I have one of these - they're quiet and very small.


Do they heat up? Do you have a pic?


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## Sickie Ickie (Jun 20, 2006)

hedg12 said:


> Some servos can be modified for continuous rotation, and you can bypass the control circuit so that all you have to do is supply 5v to make it run. Don't know about duty cycle, but I doubt heat would be an issue.


Thanks, I already know how to hack them to run continuously, but by online directions only. Have you heard anything about them heating up?


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## slightlymad (May 25, 2006)

Servo that's what the alcohol prevented me from thinking about last night thats what ya want sickie servo power some heat but not usually enough to ignite anything


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## Sickie Ickie (Jun 20, 2006)

This is what I just bought off ebay. I'll update everyone on how it works.

Hextronik HXT900 Servo









Here are the specs:

Replaceable servo gears
Size : 21x12x22 mm / 0.74x0.42x0.78 in
Voltage : 3v ~ 6v
Weight: 9g / 0.32oz
Speed : 0.12 sec/60(4.8V)
Torque : 1.6 kg-cm (22.2 oz./in.)
Working Temp : -30C~60C
Teflon Bushing, 15cm wire, coreless motor
Servo arms & screw included

cost w/shipping= $5


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## Otaku (Dec 3, 2004)

If the working temp max is 60 °C (140 °F) it won't ignite anything you might use in the articulated hand. Would you still like a pic of the gearmotor?


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## HolyTerror (Mar 11, 2009)

Hope you don't get too dissappointed there . That servo rating is WAY over - rated . That "claimed" torque is NOT anywhere near what it is in reality . I bought those for a small plane once , and was VERY upset about it . ( guess thats what I get for buying the "cheapo" ones - and I'm referring to me , when I bought them for my plane . )
Let us know how it turns out . Oh .. and btw - I don't think I have EVER heard of , or experienced any servo getting hot ... not even warm for that fact .


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## Sickie Ickie (Jun 20, 2006)

"Would you still like a pic of the gearmotor?"

yes please.


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## Sickie Ickie (Jun 20, 2006)

HolyTerror said:


> Hope you don't get too dissappointed there . That servo rating is WAY over - rated . That "claimed" torque is NOT anywhere near what it is in reality . I bought those for a small plane once , and was VERY upset about it . ( guess thats what I get for buying the "cheapo" ones - and I'm referring to me , when I bought them for my plane . )
> Let us know how it turns out . Oh .. and btw - I don't think I have EVER heard of , or experienced any servo getting hot ... not even warm for that fact .


That's what I was hoping to hear about the not getting hot. Thanks!

As for the overrated on the torque, I'm really not needing much. It's just to operate some crank fingers I'm going to rig up for Santa to play the piano- similar to the Grim Organist. The main concern I had was running the motor continuously for hours at a time and not being a fire hazard because of the white glove covering it. The grim organist doesn't have to worry about this because of exposed bones.

I'm in new territory using servos for a lifesized Santa Piano figure from scratch. LOL We'll see if I can make it come off this year! 

edit: although the other servos would be off/on for movement, the hand motors would run continuously.


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## Dr Morbius (Sep 21, 2004)

Running any servo motor continuously will wear it out in a matter of hours. Especially under load. They are meant for intermittent use, even if hacked for continuous rotation.

Gymghost tested some Hitec and other off brand servos for skull projects and found some to wear out in less than 24 hours of continuous operation. 

You should get those little motors Dave the Dead uses..I forgot the link. Maybe I can find it.


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## Sickie Ickie (Jun 20, 2006)

Thanks Doc. Good to know before I do all that work. If you can lead me to Dave's motor, that'd be appreciated.

Otaku's motor still isn't out of the running either.


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## dave the dead (Jan 31, 2007)

http://www.surpluscenter.com/item.asp?UID=2008063018195822&item=5-1587&catname=

here ya go Sickie. Not sure if this is small enough for your use, but it is a good continuous run motor, about 5 rpm, super quiet, and has decent torque.

and it is cheap.


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## Sickie Ickie (Jun 20, 2006)

Thanks, Dave!

Yepper, 'tis cheap...but the shipping isn't. $7 for a $3 motor may be a bit of a tough sell.

I like that it has torque and is quiet! Also that it can be run continuously.

4.5 x 3.5 may be a little big since I would still need to add a lever/washer for the crank.

I'll have to keep this in mind though, especially since my options are becoming fewer and fewer...


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## dave the dead (Jan 31, 2007)

buy in bulk, and the shipping becomes manageable...


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## Sickie Ickie (Jun 20, 2006)

good tip


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## Otaku (Dec 3, 2004)

Sickie Ickie said:


> Thanks, Dave!
> 
> Yepper, 'tis cheap...but the shipping isn't. $7 for a $3 motor may be a bit of a tough sell.


I know what you mean about the shipping - it's frustrating that I don't have a brick+mortar nearby that sells stuff like this. The shipping from AE is $7, too. As DtD said, check your parts bins and see if you need anything else, then place an order. It makes the shipping easier to swallow.


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## hedg12 (Jul 6, 2008)

Sickie Ickie said:


> Thanks, I already know how to hack them to run continuously, but by online directions only. Have you heard anything about them heating up?


I helped a friend with an art installation about a year ago using (I think) HiTek servos modded for continuous rotation. It ran for 3 hours at a time for 2 weeks. At the end of a 3 hour run the servos were warm to the touch, but not hot enough to start a fire. They weren't loaded very heavily, though - they were turning 12" plexiglass circles. Not sure of how long they could keep it up, but they were working fine after the 2 week show.


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## Otaku (Dec 3, 2004)

SI, here's a pic of the small gearmotor.

http://halloweengallery.com/displayimage.php?pos=-3845


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## Sickie Ickie (Jun 20, 2006)

Oh! That may be what I'm looking for Otaku! 

Is the third wire a ground?


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## Otaku (Dec 3, 2004)

Nope, it's a trigger wire that lets the motor turn one revolution, then stop.

http://www.allelectronics.com/mas_assets//spec/DCM-110.pdf


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## Sickie Ickie (Jun 20, 2006)

I'll prob go with Otaku's now. What kind of torque does it have?


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## Otaku (Dec 3, 2004)

It's actually pretty good. I was unable to stall the motor by holding the gear or the small offset pin while the motor was running.


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## Sickie Ickie (Jun 20, 2006)

That's definately what I need. All I have to figure out now is how many to buy,

Thanks to all the help in this thread everyone!


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## Otaku (Dec 3, 2004)

Otaku said:


> It's actually pretty good. I was unable to stall the motor by holding the gear or the small offset pin while the motor was running.


I should qualify this by telling you that I was using 6VDC. I don't know what the result would be at a lower voltage, but there's bound to be some loss of torque. BTW, the parking function returned the pin to the same location each time.


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## Sickie Ickie (Jun 20, 2006)

Just ordered 4.


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## hpropman (Jul 27, 2008)

what about not placing the motor in the hand but in the chest or arm or under the keyboard. you can run fishing line or push rods from below to move the fingers.


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## Sickie Ickie (Jun 20, 2006)

good idea, but I want to be able to have the arms move up and down the keyboard.


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## The_Caretaker (Mar 6, 2007)

Still could do it if you used cable in a sleeve, like on a bike look at flexible cables in the hobby shop for RC planes and cars to get a better idea.


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## Terrormaster (Sep 27, 2007)

dave the dead said:


> http://www.surpluscenter.com/item.asp?UID=2008063018195822&item=5-1587&catname=
> 
> here ya go Sickie. Not sure if this is small enough for your use, but it is a good continuous run motor, about 5 rpm, super quiet, and has decent torque.
> 
> and it is cheap.


Dave, is that the exact same motor that Electronic Goldmine has for $5.99? Bought a couple from them last year for Agnes and they're awesome. Was gonna buy another from them for the $20 challenge. The Surplus Center price is half the cost and will knock $3 bucks off my total, practically saving my ass.

Sickie, these are great motors but I can see the temptation of the auto-park on the motor Otaku recommended.


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## dave the dead (Jan 31, 2007)

Terrormaster said:


> Dave, is that the exact same motor that Electronic Goldmine has for $5.99? Bought a couple from them last year for Agnes and they're awesome. Was gonna buy another from them for the $20 challenge. The Surplus Center price is half the cost and will knock $3 bucks off my total, practically saving my ass.
> 
> Sickie, these are great motors but I can see the temptation of the auto-park on the motor Otaku recommended.


'tis the same beast Terrormaster. I have purchased from both sources.


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## Sickie Ickie (Jun 20, 2006)

Just an update. Got these small motors in and I couldn't be happier! These are perfect, and will be great for what I am using them for. Thanks again.


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