DC motors and the mechanical pieces

Thread Starter

Sparky

Joined Aug 1, 2005
75
Greetings,

I’m looking for some advice and resources regarding DC motors and the mechanics involved with connecting a motor shaft to a gear box and a wheel.

I am not familiar (at all) with dc motors and the mechanical pieces involved.

Some questions:

1)
What are some good places to purchase DC motors larger than the “small” desktop / Lego size hobby robots? I have a wooden base – roughly 2’ square and the weight involved will be 10’s of pounds. While the physical size of a motor is not a direct indicator of the horsepower I envision a motor 3+ inches in diameter ~ meaning not an inch size that I am finding frequently. I have searched “allelectronics” and seems like they are not quite there.

2)
Regarding connecting the shaft to a gearbox and a wheel – what are the pieces “called” – what do I search for? Any good resources for buying these pieces? How do a specify a correct gearbox with a correct motor – I assume I need to match something up?

3)

Are there drawings or “how-to’s” involved in mounting and connecting motor, gearboxes and wheels you can point me to?

I believe I can get a good start with controlling the motor (electronically) and so forth – I am very inexperienced with the mechanic side of this.

Thanks
Sparky
 

acciojoe

Joined Dec 7, 2011
1
Try W.M. Berg. Other manufacturers of dc motors are: Mabuchi, micomo, maxon. Many of these offer shaft couplings, gearheads, controllers, and tutorials.
 

thatoneguy

Joined Feb 19, 2009
6,359
Solarbotics has the hobby motor size with gearhead built in at affordable prices.

When searching, look for "gearhead motors", you'll end up at several sites that sell motors and gearhead either together or you pick the gearhead ratio you want to fit the motor you have.

Maxon is great for the mix-and-match selection, but it is not uncommon to spend over $100 and sometimes $200 for a Maxon motor w/gearhead, however, they are excellent motors that won't fail outside of gross negligence. Maxon doesn't really have a "hobby/low cost line" of motors, they are all professional grade, hence the price.
 

shortbus

Joined Sep 30, 2009
10,045
Don't forget auto wrecking yards. A late model car has motors of many different sizes, some with built in gear boxes. Wiper motors, door lock motors power window motors, power seat motors, heater motors and more. All using 12V.
 

Bernard

Joined Aug 7, 2008
5,784
I have 2- 250W, 22V, 11.5A right angle gear box driving 12? in wheels available: AKA guts of an electric wheel chair used as electiic tractor. Runs well on 12V, origional speed spec 7.5km/hr. Also, about 4in dia.
 
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Thread Starter

Sparky

Joined Aug 1, 2005
75
Thank you all for the help and advice.

I see from Stantor's link once one leaves the "hobby" size motor's get expensive.

Bernard - that is close to what I'm looking for - maybe a little overkill. I wish I knew how to get a wheel chair motor. I don't have access to a junk wheel chair.

Other than wrecking yards any advice to find something like a junked wheel chair motor (or equivalent) - The wheel chair motor seems so close - especially if i could gut the charging pieces and cabling with it - all would be ready to go.

Thanks again
Sparky
 

ElectroDFW

Joined Sep 2, 2011
15
I would have you check out one of the robot-building books for advice on how to mount motors to platforms, specifically Gordon McComb's Robot Builders Bonanza, among others.

I do agree with the others in that powerful motors are hard to come by cheaply, and surplus is gonna be the best way to go. Spare car window motors are a lot easier to come by than wheelchair parts. also check into the windshield wiper motors, though they might not be reversible.

--Electro--
aka The Other David
-----------------------
Procrastinators Unite! Tomorrow!
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strantor

Joined Oct 3, 2010
6,782
I see from Stantor's link once one leaves the "hobby" size motor's get expensive.
I posted those links to give you an idea what you are looking for. that is an industrial supply company; they charge industrial prices for industrial rated products. Less expensive products are available. check ebay. check google shopping. if you can't find what you want, tell me what it is and I'll check my garage. I have a small parts depot in there.
 

thatoneguy

Joined Feb 19, 2009
6,359
Bernard - that is close to what I'm looking for - maybe a little overkill. I wish I knew how to get a wheel chair motor. I don't have access to a junk wheel chair.
Find people with the old 2m-3m mesh "TV Dishes" from the 80's/early 90's, or the satcom service shop.

The dish positioning motors should be pretty much exactly what you are looking for. 12 or 24V, gearhead motors with excellent lockup when stopped (due to gearing), but decent moving speed.
 
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