Where to Find Axles, Gears For Kinetic Sculpture?

sneakyimp writes "My brother is an architect and sculptor and wants to create kinetic sculptures powered by wind, steam, and sun. He wants to avoid electrical systems and keep this mechanical. He's prepared to cast metals for custom parts if necessary, but is hoping to find a cheap source of gears, axles, and bearings for the internal mechanical workings of these contraptions. We'll need things like miter/bevel/spur/helical gears, standard and thrust bearings, and axles." Read on below for more on the details of what sneakyimp is looking for — dismembered Capsela units won't do it. sneakyimpo continues: "These parts won't need to support much power or torque (probably less than 1 horsepower / 550 ft-lbs). Ideally, we could get a kit which contains a variety of bevel and spur gears, a few axles, and standardized connect interfaces — kind of like a box of Legos for tinkering and prototyping. I found the Stock Drive Products site and it looks like an extensive catalog, but one really needs to know what one is looking for and I don't think we're there yet. I've also found custom gear manufacturers and cheap plastic hobby kits but these are either too outrageously expensive or ridiculously under qualified for the job at hand.

I was wondering if any of you robot builders or mechanical engineers could recommend a good starter kit with an assortment of gears or perhaps a supplier that deals in appropriately spec'ed gears rather than industrial-strength SUV transmissions."

Comments

Shop

[Anonymous Coward]

It's called a metal shop.
They make these things in bulk.

You can often buy some of the more "standard" pieces fairly cheaply if you're friendly. Anything else will need to be custom-made, which they can also do, but for a much steeper price.

Re:Shop

[Anonymous Coward]

Posting Anon because its directly related to me. On most of the eastern side of the country Alro carries a wide variety of metals, plastics, and industrial supplies. All sorts of materials, shapes, sizes, cutting and processing. You can also view their catalog online. http://www.alro.com/

The Mother of all Supply Stores

[Powerbear]

www.mcmaster.com

Re:The Mother of all Supply Stores

[veganboyjosh]

Seconded.

Note: At first glance, the front page of their website looks like some kind of lame link farm. Click once or twice, or enter some search terms, and see the wonder that is mcmaster-carr. This may be the most "i'm not sure what i need, exactly, but i'll know it when i see it"-friendly website or hardware store i've ever seen.

Find your local heat treat shop.

[phrackwulf]

Your average heat treater is going to have gears and pieces that get screwed up during nitriding or other operations. Since you are doing sculptures, its quite possible you don't need the case hardening that a regular customer needs. See if you can find a shop that does a lot of pinion and sun gears for example, then offer to buy on the cheap things they can't fix in re-work. Since its a sculpture, you probably don't need to go custom on some of the sizes.

Re:Mod parent up

[iq in binary]

Being a machinist, I'm telling you that the approach you just offered is a hell of alot of investment, time, and learning.

I've been a machinist for 5 years, I've worked on aerospace, medical, and defense parts. Even to this day, without a damned expensive hogging machine, it still takes alot of time and all my expertise to properly machine one gear. Keep in mind here that I'm in charge of Journeymen with decades of experience, who still come to me with questions. My employer bills my time at $65/hr, and it can take me 2 days to make a custom gear. Don't forget material or tooling, we charge you for that too.

You're better off having a GEAR shop (Note that they're often quite different from a machine shop) make your quarry, far cheaper and less hassle. Gear making can be done by a machinist, but our equipment isn't geared for it (pun intended). The fact that any given gear has 31 related characteristics to it that all have to be held to a notable tolerance makes things a royal pain in the ass.

Best thing to do is to get a Machinery Handbook (decent coin, but the best investment a tinkerer will EVER make), learn the different pitches and what not, and order the gears from there. Once you realize what it is you want to do with it, there are only three things you need to know. Teeth, Pitch, and Diameter. Pitch need to be the same, teeth and diameter dictate power transfer and at what rate. Check out McMaster Carr, or MSC. As a matter of fact, McMaster Carr has some educational material on their site, just search for "gears". Even for worm and pinions, once you know what you're going to do with them, you just have to make up your mind about size.