MathGeek

I desperately need compact (and affordable) gear boxes to build a 4-legged walker.

size should be 1.5 in x 1.5in MAX. (or something close)

I guess I could use servos, but due to my budget, I simply cannot get 8~12 servos. (The cost adds up quickly).

Is there any way to obtain cheap, small gear boxes?

I am not looking for high quality, metal, gear boxes, but just some plastic ones.

I have heard of gearboxes modified from Oven Timer Unit (OTU), but I can't get hold of OTU's.....

Is there a way to build gear boxes....?

Klaus

Have you tried an electronics hobby shop in your area? Perhaps they even have a catalogue where you can order on the net. Here in Australia they have small DC motors with attachable gear boxes advertised. Several types of gearboxes are available, eg. spur gear, planetary gear and worm gear. They have small low torque plastic parts and are inexpensive.
Klaus

MathGeek

Hm...I found some gear boxes at stores (not really cheap)

Just one question.

One gear box says it is "29 RPM"

Does that mean its max rpm is 29?

Klaus

I doubt that, there should be also an input speed which gives the 29RPM.
Ususlly gearboxes have a ratio given, like 100:1 or whatever.

The price range of these kit gearboxes here is from $AUS15.- for a simple worm gear to $AUS30.- for a planetary box, including the motor. These are a 'TAMIYA' brand.

While scavaenged gearboxes and motors often cost you nothing, you are then faced with making small couplings to join them. Easy if you have a hobbyists lathe, tricky or expensive otherwise. You also need some metal bashing skills to mount these as odd scavenged items rarely bolt straight together.
Klaus

JFDuval

For really cheap gearmotors: www.solarbotics.com

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JFDuval
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atferrari

For a different reason I've searched, few days ago for "spur gears" and Google vomited tons of data. They looked expensive, but... :?:

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Gorgon

Hi,
What about buying a cheap plastic tanks (kit). The motorized ones comes with a complete 2 motor gearbox setup.

TOK

pike

You could try converting a servo to full 360 operation. There are some guides on the net. Just google it.

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Sputnik

I have 10 identical GWS MINI servos I will sell you very cheap or trade for ?

Only a few of them have actually been used, but not very much.

They are a bit smaller than what you need, should do fine.

Heres a link to the on GWS site

http://www.gwsus.com/english/product/servo/mini.htm

bryan1

Hiya Sputnik,
Eh mate I'm interested in those mini servos so send me a P.M. if your interested in selling them

Cheers Bryan

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Sputnik

You got PM bryan