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Where to Find Axles, Gears For Kinetic Sculpture? 267

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."
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Where to Find Axles, Gears For Kinetic Sculpture?

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  • Shop (Score:5, Insightful)

    by Anonymous Coward on Wednesday October 22, 2008 @05:15PM (#25474553)

    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 (Score:5, Informative)

      by Anonymous Coward on Wednesday October 22, 2008 @05:48PM (#25475063)
      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. []
    • []

      It has mechanisms and mechanical ideas that you'd never have thought of to do all sorts of interesting movements - ideal for any dynamic sculptures etc.

      And while you're looking for power sources, consider Stirling machines. Unlike steam, they don't use water so can't boil dry.

    • by PDAllen ( 709106 )

      For the top end of the torque requirement, yes - or go to a junkyard and disassemble a few gearboxes and trans shafts.

      For any smaller more delicate bits, where you do not need that sort of torque, try to find a box of old-style (metal) Meccano on ebay / some car boot sale, and buy some rods of the right width (1/8 inch?) to get decent length axles.

  • by Powerbear ( 1227122 ) on Wednesday October 22, 2008 @05:16PM (#25474559)

    • by veganboyjosh ( 896761 ) on Wednesday October 22, 2008 @05:21PM (#25474673)

      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.
      • by Facegarden ( 967477 ) on Wednesday October 22, 2008 @05:35PM (#25474885)


        also, i think they just went out of business but i'm not sure: []
        i'm not sure where you're located though, you kinda need to be there to know what to get.
        surplus places are good when you're making custom art-like stuff.

        • Why do I get a "Virus Detected" from Avast when I try to go to that site? :)
          • Why do I get a "Virus Detected" from Avast when I try to go to that site? :)

            Really? Maybe avast is crazy, i don't get any errors and the company is indeed legitimate. Maybe their server got hacked but they are just a little surplus store, they wouldn't do any harm on purpose.
            I don't really like AVAST anyway...

      • by evanbd ( 210358 )

        Thirded. Between easy searching, excellent data on most of their parts, and a *wide* range of items, there's really not much more you could ask for. Prices aren't the cheapest you'll find, but they're usually competitive. You pay a mild premium for the huge inventory, fast shipping times, and truly excellent customer service -- but it's worth every penny, especially for small quantity orders.

        For things like gears and sprockets and shafts, they won't have every conceivable size -- but the sizes they lack

      • Note: At first glance..
        Precisely. Their printed catalog is thicker than the phone book, with thinner paper and smaller text. ;-) You can browse by category, or you can browse by keyword. Either way, you can build damned near anything you could conceive of from what they sell.
      • by pz ( 113803 )

        McMaster is amazing. I have yet to encounter another company that is nearly as efficient.

        When I was in LA, my morning orders would arrive often THE SAME AFTERNOON, which includes the latency of the university delivery system where I worked.

        Now that I am in Boston, my orders arrive THE NEXT DAY without fail, again, including the latency of a large institutional delivery system.

        Sure, sure, you say, that's easy, just pick the ultra-fast-pronto-first-thing delivery when you place your order. This was with the

    • by afidel ( 530433 )
      I would try something more along the lines of an industrial surplus store like HGR [].
    • Re: (Score:2, Informative)

      by Anonymous Coward [] Small parts has a lot of stuff that's not cheap, but can be bought in small quantities.
      The modern toothed belt technology is quite good for power/weight precision and you can go back and buy more.

      The other thing to do is look for a local old time hardware store or industrial machine shop supply store if you live in a decent sized city. And it never hurts to browse ebay.

    • That site does look useful. However, it looks a bit pricey. Am I right in understanding that spur gears [] start at $8.61 EACH and go up from there? That seems a bit pricey for tinkering.

      I'm also puzzling over the plain bore. It might well be machinable but I don't want that. I want gears that are easily mounted using a setscrew or which attach to a hexagonal or square shaft. I want to avoid using taper pins, welding, etc.

      • Yeah mcmaster is definitely expensive... but they stock everything, ship same day, top notch customer service, and they have huge warehouses in a few big cities. If you live nearby you can just drive to and pick your stuff up an hour after placing the order, with saturday hours too. That's why I order from them, anyway.,,, are other similar suppliers I use for this kind of stuff (mostly metalworking tools in my case but smallparts probably ha

        • Thanks for the tips!

          My brother might be up for the machine shop approach, but I'm gunning for the prefab gears thing. I checked and they do have a few gears, but the selection is pretty limited -- mostly very small bore sizes. They do have some larger bore (.625 inch) but those gears is PRICEY...$30 and up. I'm thinking 1/4" bore, need some spur gears and bevel gears with various tooth counts and a couple of mounted bearings.

  • Your toybox? (Score:4, Informative)

    by SQLGuru ( 980662 ) on Wednesday October 22, 2008 @05:18PM (#25474577) Journal

    I'm no expert and I didn't really read exactly what you were looking for, but what about going to places like Goodwill / Salvation Army Stores / Garage sales and disassembling some of the older toys that are likely missing parts. I'm sure an old music box has some good quality metal gears, etc. and you probably won't spend more than a few bucks.


    • Re: (Score:3, Insightful)

      by evanbd ( 210358 )
      You have a music box with 1HP rated mechanical components? Now that sounds like an interesting contraption. Pics, please!
  • by Cliff Stoll ( 242915 ) on Wednesday October 22, 2008 @05:19PM (#25474603) Homepage
    • by spud603 ( 832173 )
      similar, if you're in Portland, OR, is Wacky Willy's. Amazing shop.
      but oh, no! [] it looks like Wacky Willy's is gone. That is truly sad.
      • by PopeRatzo ( 965947 ) * on Wednesday October 22, 2008 @06:02PM (#25475241) Journal

        If you're in Chicago, there's a joint called American Scientific and Surplus out on Milwaukee near Bryn Mawr.

        Not only will you find all sorts of gears, axles, motors, bearings etc (really cheap), but also fresnel lenses, lab coats, powerful lasers, prisms, switches, bombsights from WWII-era bombers, jacob's ladders, lenses for telescopes, microscopes, lab glassware and about a million other cool things. Often, the use of particular objects in their inventory is not clear, but they'll sell it to you anyway. It's really worth talking to the guys (all guys) who work there, because if you think you know some geeks, you haven't seen nothin' 'til you've seen these dudes. Bubbles from Trailer Park Boys would seem normal compared to these fellas. But nice? they're all really nice and helpful and probably have everything you need to make a dirty nuke in the back. Oh, they sell lots of protective gear, too, which is helpful.

        They've got a website and will send you a catalog, but you've got to actually go into the place for the stuff you want (or call them and talk to one of the guys who work there). I'd put a link here, but I'm being called to dinner.

    • Re: (Score:3, Informative)

      by wiggles ( 30088 )

      And if you're within 2 hours drive, their store [] in West Chicago, IL is well worth the trip.

      • by interiot ( 50685 )
        I second that. My sister works at the one on N Milwaukee [], and the place is a real hoot. Just be prepared to spend two hours there if you've never been there before. If you go looking for one specific part, you won't necessarily find it (since it's a surplus place), but sometimes they have 2+-feet-tall capacitors or other gems that make it worth visiting just in case. And if you don't know what to buy somebody for Christmas, they have a ton of geeky/silly/cheap stuff that are better than the old standby
    • Consider me yet another rabid advocate of American Science & Surplus. I've been a big fan of theirs since they were called JerryCo back in the eighties. I, too say, if you can possibly get to the stores, then do. Also, don't be afraid to call if you don't see what you need. They may only have four of something and not have bothered to do a listing for it.

      I don't know the words to say how kickass these guys are. Back in my prototyping days I moved to Milwaukee partially just to be able to get to their
    • I had run across that site before but had to dismiss it. As you can see [] it has little to offer in the way of specific gears. They're all plastic and they don't seem to have any relation to each other. I need something where I can get a bit more specific. I'll need to be able to gear things down by exact amounts, get bevel gears or worm gears, etc.

  • Seriously, this place has a ton of random stuff. You would have to walk through there, but it is a nerd/engineer's wet dream. Anyone else know of this place? []
    • I am going to disagree with the American Science recommendation because:
      A) I have been going there for years for things like this (hope springs eternal.... cross fingers they've got what I need....Nope!)
      B) I have been very disappointed and end up buying from McMaster Carr Supply , Grainger or Small Parts Inc. to complete whatever bizarro project I was doing (usually for TV or Theater).

      I USED to rely on Am Science, and there was a time when my shop was basically a mirror of the American Science & S
  • bikes? (Score:5, Insightful)

    by spud603 ( 832173 ) on Wednesday October 22, 2008 @05:19PM (#25474615)
    I'm not sure if this will fit your needs, but old used bicycles are cheap to find and full of cables, levers, cranks and gears -- all compatible with one another. (small wheels make good belt-pullies too)
    I've seen some great and complex stuff made from bike parts.
    • Re: (Score:3, Informative)

      I spend most of my non-working, non-sleeping time at our local bike cooperative. At last count, there are about 120 of these around the country. We take in old unused bikes in any condition, refurbish them, and get them rolling again. This is an awesome source of parts, if only to get the juices flowing or modeling, until you've got a more concrete design.

      Check out the "directory" link at the bicycle collective website [] and see if there's one near you.
    • Excellent suggestion. He's already working this and will be going junking this weekend. Bikes offer a nearly infinite range of gear ratios and are readily available and cheap. The downsides for me are that 1) transmitting power must be done via chain...the big wide chain enclosure might force some limitations on the shape of the sculpture that axles wouldn't; 2) We haven't figure out how to get a lengthy shaft connected to a bicycle gear yet...this will probably be fairly obvious when he starts taking th

  • car scrapyards (Score:2, Informative)

    by inzy ( 1095415 )

    is the glaringly obvious answer

    although it depends on the size he wants

    there'll be plenty of parts there - differential, drive shaft, prop shaft, gearbox, flywheel, starter motor, steering will all have parts he can use, and from the last time i was in a scrapper they'll be pretty cheap particularly if he goes for the older cars.

    might need some dismantling though, which isn't easy on a rusting heap

  • Meccanno? (Score:2, Insightful)

    by plalonde2 ( 527372 )
    Meccano [] is made for small scale kinetic sculpture.
  • by stubob ( 204064 )

    Spare bike parts. Should be cheap, strong enough for a couple hp, pretty standard. More chain drive than gear drive, but the idea is the same. Lots of variety in bearings.

    An old self-propelled lawnmower should have a belt drive to satisfy your requirements as well.

    Are blenders direct drive, or are they gear reduction? 500 watts is around 1 hp, so that could work too.

  • Mechanical. (Score:5, Funny)

    by the_other_chewey ( 1119125 ) on Wednesday October 22, 2008 @05:21PM (#25474657)

    He wants to keep this mechanical.

    As opposed to...?

    Magnetically stabilised plasma girders?
    Holographical joints?
    Fusion Axles?

    • You seem to have inexplicably skipped over four words in the sentence you quoted.

      • You seem to have inexplicably skipped over four words in the sentence you quoted.

        That was intentional. I thought about add ing "...", but considered it unnecessary, as it doesn't affect my point.
        What exactly makes electricly powered kinetic sculptures "unmechanical"?

        • Re: (Score:3, Insightful)

          by glwtta ( 532858 )
          That was intentional. I thought about add ing "...", but considered it unnecessary, as it doesn't affect my point.
          What exactly makes electricly powered kinetic sculptures "unmechanical"?

          Those were the four words that let you know that he meant purely mechanical, ie not electric/electronic. It's a perfectly common use of the term.

          Pedantry is fun and all, but at a certain point you are just being disingenuous.
        • When you remove or add words and don't indicate somehow that you have done exactly that, you are no longer allowed to call it a quote. This is not dependent on how well the mutilated quote supports your argument.
  • Here's a "interesting biz in our area" piece in my local paper. Contact them, or any other local design house:,0,6635443.story []
  • Junkyard (Score:4, Informative)

    by theguru ( 70699 ) on Wednesday October 22, 2008 @05:23PM (#25474707)

    Transmissions, differentials, and front wheel spindles on RWD cars ready for the crusher.

    • Transmissions, differentials, and front wheel spindles on RWD cars ready for the crusher.

      Did you see the site he linked?
      Car parts will be way too big compared to the examples he has used [].

      I'd say he's looking for anything from hobby quality RC parts (small) up to motorcycle & atv parts (medium).
      So the place to look would be hobby shops and motorcycle/offroad repair shops.
      I leave out bicycles because they won't have the range of parts he's looking for.

      That said, I don't think he's going to find anything in the small-medium range which can handle 550 ft-lbs of torque. Most cars can't handle th

      • by theguru ( 70699 )

        I did, I initially thought he was just talking about the smaller stuff for prototyping.

        You'd be surprised though at some of the smaller parts you can get from a junkyard. Don't overlook speedometer heads, angle drives to drive a speedometer, power seat motors, power and manual window mechanisms, wiper motors, tape decks...

    • Hmmm...These are probably way overbuilt for this task. I doubt we'll have even one horsepower. Also, I'm not exactly the transmission-disassembling-uber-greasemonkey that you might think I am. I was rather hoping for something smaller, lighter, cheaper, and easier.

      • by PDAllen ( 709106 )

        You keep saying this, but HP isn't really the point. Spin a cheap plastic gear at 20k RPM and you can probably get >1HP through it without too much trouble, but spin it at 10RPM with 0.05HP on it and you'll be lucky to see it last a minute before the teeth break. You need to care about the force being applied to the gear teeth - and 550flb is quite a lot of torque, so little gears will probably break, thin axles will twist out of true or simply shear. Two options - go for heavy stuff, or gear things up s

  • Torque... (Score:3, Informative)

    by actionbastard ( 1206160 ) on Wednesday October 22, 2008 @05:24PM (#25474715)
    550 ft/lbs is one helluva lot of torque. Try your local car recycler.
    • by Timmmm ( 636430 )

      > 550 ft/lbs is one helluva lot of torque.

      No it isn't. 550 ft-lbs might be! Nm is a much more sensible unit though.

    • Indeed it is a hell of a lot of torque. That's the kind of torque you get from a supercharged 6 litre V8. SUV transmission is precisely the kind of thing you would need, and not from a small SUV either.

      The power thing doesn't much matter, it's torque which moves things and breaks driveshafts. An engine more powerful than 1hp but still with 550 lbs/ft would just turn faster, not with any more force. (power = torque x rpm)

    • Re:Torque... (Score:5, Informative)

      by John Hasler ( 414242 ) on Wednesday October 22, 2008 @06:57PM (#25475891) Homepage

      > 550 ft/lbs is one helluva lot of torque.

      ft/lbs is not torque at all (torque comes in lb-ft). If it's anything it's something like linear feet per pound of string. However, the article says ft-lbs, not ft/lb. A ft-lb is a unit of work. Work per unit time is power. 550 ft-lb/sec is one horsepower.

      • There is no difference dimensionally between a lb-ft and a ft-lb. It's a conventional distinction only to clarify whether you mean work or torque. The reason the two quantities have the same unit is because one of them incorporates an angular term, which is dimensionless. From a dimensional standpoint there is no difference between a ft-lb and a lb-ft. Thus the danger of trying to equate dimensional units with physical variables.

    • My bad. My physics muscles have atrophied. I took the 550 ft*lbs from the definition of horsepower, having forgotten that there was a time element in power that is absent from torque.

      It would be considerably less than that. I'm imagining at max a 10-ft diameter windmill driving this thing. Any estimates about how much torque this represents would be welcome. Any discussion on the relation between torque and power that don't involve equations would also be welcome. I can get the equations from wikipedia

  • (Score:3, Informative)

    by msauve ( 701917 ) on Wednesday October 22, 2008 @05:24PM (#25474719) [] has a selection, but not really cheap.
  • flea market (Score:3, Informative)

    by OglinTatas ( 710589 ) on Wednesday October 22, 2008 @05:26PM (#25474749)

    old clocks are chock full of brass gearing and bearings. steer clear of antique shops though, since you will definitely pay way to much for something you are planning on destroying anyway.

    Also, kinex and lego mindstorms have nice stuff, but I think you are talking about much larger structures?

    Bicycle repair shops come to mind for stuff larger than clockwork.

    hobbyist organisations no doubt have resources to check. Check out Make magazine's forums for people who do what you are planning []

    • It's amazing the range and quality of parts in a dead office copier. Same goes for heavy duty printers and even scanners. Belt drives, couplings, pillow blocks, and on and on and on. But watch out for the obvious. If you think disassembling a car was messy, wait until you're getting smeared with three kinds of lubricant and toner is getting into every nook and cranny of your body. Man, that stuff makes sand seem unintrusive. Keep a dozen rolls of paper towels on hand. Seriously.
  • Try a junk yard (Score:4, Informative)

    by techess ( 1322623 ) on Wednesday October 22, 2008 @05:26PM (#25474751)

    If you are looking for parts try a junk yard. You may have to do some driving to find the right "kind" of junkyard. Some specialize in parts that can be re-used in vehicles as originally intended. These junkyards are expensive. Look for a yard in a small town or in the country. I've been to junkyards that will sell you stuff by how much you can carry or how much you can fit on a cart. These are the best because you can get a lot of stuff pretty cheap.

    Bring a good set of gloves, make sure your tetanus shot is up to date, and have a ton of fun digging through the junk.

  • Meshing gears are far more expensive than chain & sprockets and require greater precision when installed or they'll wear out quickly. They also need more protection from the elements and do not like at all to be dirty. As for axles, I assume your friend can weld a shaft onto a standard spindle. If you can afford timing belts and toothed sprockets, you can maybe eliminate the need to regularly lubricate the thing - so long as you use sealed bearings. If you insist on gears, try Boston Gear and they'l
  • junkyard? (Score:3, Informative)

    by mikeee ( 137160 ) on Wednesday October 22, 2008 @05:27PM (#25474767)

    An automotive junkyard might be a good bet for some of that sort of stuff - not just transmission bits, there are plenty of other motors and gears (windows, starter, various pumps) you could strip parts from. You'ld probably need a pretty good idea of what you want exactly to go that route, though.

    • Ur Doin It Rong (Score:3, Insightful)

      You'ld probably need a pretty good idea of what you want exactly to go that route, though.

      Traditionally the form of a kinetic sculpture is determined by the parts available, not the other way around. The challenge is to make something great given a whole lot of stuff that's not. Then again, most artists are poor and good scroungers.

      Idea: find an old factory being decommissioned and start stripping machines. Pay slightly more than scrap if you need to.

  • Steampunk supplies (Score:3, Informative)

    by Authoritative Douche ( 1255948 ) on Wednesday October 22, 2008 @05:31PM (#25474831)
    Google suppliers of steampunk stuff. Lots and lots of gears and widgets to be found in weird places.
  • McMaster-Carr (Score:2, Redundant)

    by Goldsmith ( 561202 )

    Perhaps the greatest company in the world []. McMaster has a huge inventory, reasonable prices, quick delivery and an easy to use website. If you want gears, machinable material, welding supplies, or anything else a kinetic sculptor would need, you should find it there.

  • Reasonably heavy duty, cheap, and readily available.

  • by phrackwulf ( 589741 ) on Wednesday October 22, 2008 @05:39PM (#25474935)

    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.

  • Lots of surplus companies sell that kind of stuff. Check out surpluscenter [] for instance.
    • They have a good selection, and are quick to ship. We purchased many parts for our entry in Baltimore's Kinetic Sculpture race. []

      If you're looking for a good selection of gears, dig down into the Power Transmission / Transaxle section, and take apart one of the 2-speed Peerless transaxles. There are bevel gears, a differential, and several nice spur pairs on shafts. Sometimes this transaxle pops up for less money, but not much less.
  • Depends on size (Score:5, Insightful)

    by WillRobinson ( 159226 ) on Wednesday October 22, 2008 @05:52PM (#25475109) Journal

    As others have written there are a several places to get good parts. Of course it depends on the size of the sculpture, and weight of the pieces.

    I build pick and place robots for a living, excellent resources are always good to have.

    Besides Granger, McMaster there is also:

    Standard Din sizes, and also american []

    another good one stock drive products []

    And If you need to handle larger loads, as I expect your sculptures to need. Seek your local power distribution company (as in gear boxes).

    This is one of many (Motion Industries) []

    for a large list click below []

    • Thanks for the thoughtful post. I had seen That was one of the links in my original post. Mdmetric looks good but I'd have to call them I guess. looks super handy -- a nice orderly search by gear parameters. I'm puzzling over the means by which these gears get coupled to the shaft. There's no setscrew and the shaft hole is perfectly round. Would that be a weld? Do you have to machine it? How do you keep the shaft coupled to the gear?

  • by steveha ( 103154 ) on Wednesday October 22, 2008 @05:54PM (#25475135) Homepage

    Look up Kinetic Sculpture Racing: []

    The guys who do this build wacky and weird human-powered contraptions. These are supposed to go on land, water, sand, and mud, and be only human-powered. (Some vehicles fail in one or more of these categories; but they can avoid being disqualified by providing sufficient bribes to the Kinetic Kops. In plain sight of all onlookers, of course.) Vehicles that can do all of the above, without any "pilots" leaving the vehicle to adjust things, get the "ACE Award" for good engineering.

    One of my favorite kinetic sculpture vehicles is a behemoth that carries four people, each of whom provides power to one wheel, and one of whom has the steering wheel and brakes. I have also seen a vehicle that carried eight people, all powering a common drive train.

    Anyway, these races have been happening for decades, and you can find the discussion lists where the KSR community discusses where to get parts, how to make things strong and reliable, etc.

    For the glory!

    • I checked the wikipedia link but there's no mention of a forum or community. Any idea how to get in touch with these folks? I see the race is this weekend. It's my girlfriend's birthday though...maybe I can talk her into going...

  • has things along these lines and I've ordered various hardware from them in the past.

  • Auto junkyard.

    The Black Hole [] if you're close enough.

    Most any plant has a pile of junk. Many gizmos in there.

    • I live about a half mile from the Black Hole.
      Probably has anything you could want, if only you could find it amongst all the junk.

  • Make your own (Score:5, Interesting)

    by uqbar ( 102695 ) on Wednesday October 22, 2008 @05:57PM (#25475173)
    Eric Freitas [] is an artist/clock maker that makes all his gears, screws, etc. by hand. He has step by step photos showing his techniques on his site if you want examples on how it's done.
    • thats what i'm doing, but its a very serious investment in tooling, machinery, and learning.
      there really should be a reasonable place to buy basic gears at close to the cost of the stock.

  • I'd approach it this way. Ask yourself what applications require similar power transfers. The first two things that come to mind are riding lawn-mowers and agricultural food handling. A transmission off an old riding mower would give you a great start. Forward/reverse, and several ratios. Also don't rule out belt driven systems. They are cheap and easy to work with. Go to your local 'motor, pump, & power transmission' shop where you'll find an endless supply of axles (custom made & off the shelf), p

  • W.M. Berg (Score:2, Informative)

    by Hefner ( 1391827 ) [] McMaster is definitely good, but I've found that WM Berg has more to offer in the area of pulleys, belts and the like. They may not qualify as cheap, but they can also be used as a reference...
  • What you really want is a Berg [] breadboarding kit. This is the pro version of a Mecchano set. Expect to pay something in low four figures for a full kit, although you can buy parts separately.

    The usual suppliers are Stock Drive Products, Small Parts, Inc., Berg, Boston Gear, and McMaster. The first two mostly stock miniature parts; the last two offer larger sized components. Incidentally, if you haven't worked with gears that carry significant loads, go to the Boston Gear site and work through their "

  • Ditto on McMaster-Carr. They have hardware, gears, electrical goods, tools, etc., that your local Home Depot won't even think of stocking. Need weird materials like sheet brass, Bakelite tubing, solid nylon rods for machining?, they'll have it. I work in Los Angeles; here if you get your order in before you stop for your first cup of coffee, it'll frequently shop up that very same day. Heck, one time, just as I was about to click the Submit button on their web site, the UPS guy tapped me on my shoulder,
  • by Gordonjcp ( 186804 ) on Wednesday October 22, 2008 @06:24PM (#25475485) Homepage

    And also bits of old garden machinery.

  • Unless you are recycling something, metal gears are really expensive. Plastic ones are generally extruded or formed rather than machines, so their price is less, but the capacity is less, too.

    Pulleys and belts are relatively inexpensive, and can handle a lot more misalignment. There are cogged pulleys and belts, if you have timing applications.

    As others have posted, is the key reference. Their prices range from competitive to outrageous, depending on the item. Their shipping alwa
  • This company [] has amazing kits. You can build working machine tools if youre so inclined. Also [] has some cool stuff thats much less spendy.
  • Big Blue Saw (Score:3, Interesting)

    by chroma ( 33185 ) <`moc.gnirpsdnim' `ta' `amorhc'> on Wednesday October 22, 2008 @06:55PM (#25475867) Homepage
    I would like to put in an entirely self-promoting word for Big Blue Saw []. 12 pitch (and possibly finer) gears come out just fine when waterjet cutting, and can be a lot cheaper than having custom gears made at a gear specialist. See my photos of an aluminum gear made for a fighting robot [].
  • Your local TSC store has all sorts of belts, gears, pulleys, hydraulic cylinders, etc. Not sure where you are but they seem to be all over the USA.

    Even most Ace hardware stores carry a good supply of pulleys and belts for all sorts of applications.

  • First of two, there is a neat range of stuff at []

    Second of two, you can do nifty things with just steam and pistons, but I assume you'll be doing that anyway.. =p

  • I live in a ritzy town near boston, and the stuff that gets thrown out on trash day is unbelievable....
    although not sure gears are high on the list
    The army has some second hand warehouses
    McMaster carr - as prev poster noted, they are fabulous; never out of stock and always next day - you don't need to worry about where you put that extra stuff: never order extra, let mcmaster be your stockroom
    Universitys sometimes have good stuff; in the 90s MIT had a whole building full of vacumn tube oscilliscopes; I don'

  • A bit of a site plug but my site, is a site that aggregates steampunk [] listings on eBay and separates them into categories. Lately, I've noticed a lot of gears grab bags popping up for all the steampunk crafters out there. The site updates every time you reload so I'd recommend checking back daily to see if there's any new loot.

    Often times you can find an amazing assortment of spare parts for dirt cheap, certainly cheaper than these other places that people have linked. Sorry for the s

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