Reusing Motors From Washing Machines

Big ol’ motors are great when you need to get a big job done, but they can be expensive or hard to source new. However, there’s a source of big, fat, juicy motors right at home for most people – the garden variety washing machine. These motors would usually require a special controller, however [Jerry] is here to show us how to hack the controller that comes with the machine.

The hack begins as [Jerry] decides to gut a Maytag MAH7500 Neptune front loader. Many projects exist that borrow the motor but rely on a seperately sourced variable frequency drive, so the goal was to see if the machine’s original controller was usable. The machine was first troubleshooted using a factory service mode, which spins the drum at a set speed if everything is working correctly.

From there, it was a relatively simple job to source the machine schematics to identify the pinouts of the various connectors.  After some experimentation with a scope and a function generator, [Jerry] was able to get the motor spinning with the original controller doing the hard work.

It’s a simple hack, and one that relies on the availability of documentation to get the job done, but it’s a great inspiration for anyone else looking to drive similar motors in their own projects. The benefit is that by using the original motor controller, you can be confident that it’s properly rated for the motor on hand.

Perhaps instead of an induction motor, you’d rather drive a high powered brushless DC motor? This project can help.

51 thoughts on “Reusing Motors From Washing Machines

  1. this is a useful article, but the “garden-variety” salvage washing machine and/or dryer usually has a single-speed capacitor-start induction motor that requires only the simplest of controls and these have neen running shop tools for nearly a century. High end appliance VFD motors are neat but new and much scarcer since the appliances they’re in are the profitable end of white-goods manufacturers’ product lines and much more expensive.

    1. One consideration, albeit a small one for a hacker, is that the motors in wash machines and clothes dryers do not have a typical mount. Note how the motor is physically attached in the machine and design a corresponding mount or modify the original mounting plate.

    2. “High end appliance VFD motors are neat but new and much scarcer since the appliances they’re in are the profitable end of white-goods manufacturers’ product lines and much more expensive.”

      But the replacement parts (controllers/seals/etc.) and repair labor are also much more expensive, so just as likely to be dumped.

      1. That’s why I continue to rely on old-fashioned Maytag A18 and A21 top-loaders (and their complementary dryers). No difference mechanically between the home-use version and the commercial laundry version.

        My parents owned a laundromat while I was growing up, and I learned how to fix just about everything Maytag (and had the service manuals for them as well.) Even in the worst case scenario when the drum seal was too far gone to replace (special tool, 2+ days, and lots of grease made it not worth the effort to actually fix), all I had to do was go down to Goodwill, pick up another A21 for $50, take off the home-use timer assembly and replace it with the coin slide unit.

        I hope to be dead before the world runs out of A21 parts. Fortunately, Maytag hasn’t even retired the assembly lines in some parts of the world for the even-older-style wringer washers they used to sell.

        1. Unfortunately you’re saving on washing machine bits at the expense of all your clothing and substantially more water use.

          A front-load washer uses a fraction of the water (particularly important if you’re using warm or hot water) and doesn’t cause nearly as much wear.

          Ditto for dryers. Buy a drying rack. If you need stuff dried faster, get a fan and/or cheap dehumidifier.

          Your clothes will last far longer and you’ll save on utilities. In winter time in cold places, your clothes dry lightning-fast and you get some help with keeping humidity levels up.

    3. Don’t know where in the world you are, but in the UK, almost every washing machine is capable of variable speed – mine is entirely typical and runs the drum from a few RPM while soaking up to 1600RPM spin.
      I can’t think I’ve seen a different design in a home in the last 25 years.

      1. Same here – even cheapy ones have advanced motor control these days and mostly have for the last decade or so.

        About time we had a few more HaD articles on this stuff though as white goods are so often dumped for minor faults.

        1. Unfortunately my local county’s dump has giant signs saying you can’t even ENTER the area where they’ve moved all the dumped appliances; there’s a drop area and stuff is quickly moved to the ‘fenced in’ area. The battery recycling area has a giant sign telling you you’re committing theft if you take any of the batteries.

          Seems the county is selling the stuff to recyclers and they don’t want you and I to grab that lithium ion tool battery…

    4. I would say the ““garden-variety” salvage washing machine” has a series wound brushed universal motor these days. Sometimes a combination of an induction motor for washing with a brushed motor for the high rpm of the spin cycle (up to 1400 rpm at the drum, so at least 15000rpm for the motor..
      One machine (probably built 30yrs ago) had a permanent magnet DC motor. Rated from 12V to 200V with ceramic hybrid modules in the controller. Probably not the cheapest device when it was bought.
      40yrs ago they had sometimes only induction motors but much slower spin cycles, like 600rpm at the drum. And the old Miele machine of my grand parents from the 1960ies had a real 3 phase induction motor with several sets of windings for different speeds. Yes the washing machine used 3 phase power! And this motor got a second life with a grinding stone disc.
      Now the brushless VFD drives are increasingly used.

    5. Single-speed ? I think I have see a washing machine with “bi-speed” (slow for washing, high for whirling) only once in my life… It was 20 years ago, and it was an very old cheap machine…
      The four motor on my shelf all come from multi-speed washing machine and they are not new…

  2. With the poorly designed seal in front loaders the bearings are going now, they are filling the junk stream now. I need to do a bearing change! Fixed a solder joint problem in the controller years ago. Both would cause the washer to be junked. That’s when I realized the new technology in use. The old top loading GM model had a tranny and loads of mechanical stuff. The front loader has one belt and that’s it.

    However much hangs literally (the whole load) on that bearing and it’s seal against water. Then there is the problem of the spider that connects the shaft to the drum (pot metal) lawsuits etc. What happens when one of the 3 arm breaks at spin? It rips holes in the outer case!

    TIP! Keep that door open all the time when not in use to prevent corrosion. Don’t use fabric rinse-slime.

    1. Also, a bit of water gets past the seal near the bearing. I found that the drain hole designed to deal with that leakage was too small. Larger hole, new bearing. Going strong ever since.

  3. Don’t we have a be-nice comment policy here?

    Getting into the machine’s controller to make it obey signals that weren’t its original wash programs is a hack in my book. I’m not sure if you’re deliberately ignoring that.

    1. A motor doesn’t have “original wash programs,” nor does the control have any internal or external identity… Either the motor recieves it’s designed amp/voltage or it does not, it spins or it sits motionless. WHY has nothing to do with it

  4. But if you’re going somewhere, sometimes the original circuit is fine.

    You can take part something without knowing what the whole thing does. But intact, the circuit gives information about the parts. So maybe no information about that stepper motor can be found, but in-circuit the IC controlling it provides information, and you may as well just copy the circuit intact. That. exotic crystal filter may not have a number that uncovers a datasheet, but looking at the circuit will show how it expects to be terminated.

    Sometimes if you use one part, you might as well bring associated parts with it, because otherwise you’ll have to recreate it in some other way.

    “Hacking” is about exploring, and that includes making maps. Other people need the map before they start.

    Michael

  5. Brushed universal motors are more common in washing machines, by orders of magnitude. They’re trivial to run at full speed – just apply AC or DC to both windings at the rated voltage. Trivially reversible too, just reverse one winding. Easily speed-controllable – use a triac or mosfet chopper!

    I also suspect that a big hobby BLDC controller would be an affordable solution to the problem of running BLDC motors from appliances, though you end up with a terribly high-voltage DC bus.

    1. I have actually been following this line of thought for a few months…
      I need a set of large motors to help drive a very large satellite dish mount, and there seem to be no end to the new “DC-Drive” and “Multi-phase” motor marketing that indicates some more intelligence behind the drum than just a regular big motor.

      A pair of big salvaged brushless motors and some hackaday.io custom controllers might make this a good spring project.

      1. For your satellite dish, consider the auto parts market. Power seat motors are pretty beefy linear actuators, and power lift-gate motors are bigger still. I have no idea if they’d give you the sort of motion you need, but at least give ’em a look.

        For even bigger still, there’s always electric power steering…

        1. I would expect a windscreen-wiper motor to be more than grunty enough to move even a big dish. For moving a big mechanical thing, getting a slop-free transmission will be your biggest hurdle; the electrical-drive details on the motor are but minor details.

          You can also get cheap DC linear motors on eBay, good for hundreds of kg force.

          1. My parents have an electric driveway-door. The motor looks just like a truck windshield wiper motor, operated at 24V. Driving the heavy welded steel door with rack and pinion. So te internal worm drive makes these motors quite strong.

      2. How large of a dish are we talking about here? You know that linear actuators built specifically for C band dishes are still available right? In fact there are still people using those dishes right now, mostly hobbyist who are into FTA and searching for wild feeds. Sure you can build your own, but at the end of the day, it might be easier and cheaper to use something already available.

    2. Universal motors in washers? Not sure where you found those. The main motor is going to be some sort of induction motor (single or three phase), or BLDC in newer washers, and the pump[s] are almost always shaded pole motors.

      1. The main motors, at least in all the frontloaders I’ve seen, are not induction machines because they need accurate speed control. Google for “washing motor brushes” or “washing motor bosch” and see endless pictures of universal motors.

        Fisher & Paykel are (in)famous for using and pioneering BLDC main motors, though I got the impression they were a big custom pancake thing integrated with the back of the drum, not a neat little motor module that can be pulled out and reused per the video above.

        Sure, the pumps are wet-rotor shaded-pole or BLDC, but I’m talking about the 1/3 HP thing that runs the drum.

        I guess you might see induction motors in a washer with a mechanical transmission?

        1. The accuracy of the speed control would be more than good enough in an induction motor. It’s the needed range of speeds what rules them out for “modern” machines without a VFD. <100rpm for gentle washing cycles and up to 1600rpm for the spin cycle in some machines. Traditionally both through a belt drive with some 20:1 speed reduction. European top loaders are not very different to front loaders in this regard as both have a horizontal shaft.
          1960ies Miele: 3ph induction motor, probably quite slow spin cycle. The motor offered 2,4 and 8 pole operation.
          Machines from the 1970ies or 1980ies definitely brushed motors, which are still in use in cheap machines these days.
          My machine from 2015 already has a brushless direct drive without a belt. It is wonderfully quiet and was not expensive (€400), the cheapest would have been a little under €300, but loud and lower rating for efficiency and washing results.

  6. Neat article. Interesting use of materials. I grew up with washer and dryer machine parts around me, especially once the Whirlpool plants started closing. Lately, I’m finding where the metal sheeting was re-used and made for other applications and I even found a few washer shaft bike “pegs” that were custom made for me to sell on the side.

    1. I wasn’t sure if the ultrasonic, microwaves and/or ionizing radiation was sterilizing everything first. Oh yeah… if someone wants to market things they can.

      Reminds me of growing up and being told never to mix ammonia and bleach together or use together when cleaning. Makes sense why I’m always having allergic reactions to Alkylamonium Chloride and I don’t think it’s a psychagogic reaction.

      I don’t notice anything when I use hydrogen peroxide.

      Why wouldn’t we want oxygen?

      Why would we want ammonia or bleach?

      1. Ammonia is cheap, much cheaper then H2O2, same for bleach.
        Also, the loose oxygen which you can’t see/feel/smell is a potential fire hazard, you definitely can smell ammonia ;-)

        And FYI normal oxygen (O2) doesn’t do much for you, all the cleaning/bleaching action from peroxide comes from single atom oxygen reacting with almost anything

        1. I hear you. Hydrogen Peroxide is not cheap. Is interesting when thinking observation of chlorine and iodine. Iodine residue is obvious and chlorine is invisible pretty much though more volatile however does leave a residue.

          I never really used ammonia other than silver plating glass for a telescope mirror I made. The mix concern, paranoia of relation to all the meth labs in the area or maybe the smell of it kept it out of the house for the most part.

      2. I always thought the dangerous thing would be to mix bleach with acids (liberates chlorine). What reaction has to be expected from ammonia and bleach? It can not be an alkylammonium salt, as there is no carbon present.

        1. I had to look online and find out. I am still going by hear-say to this day. I first thought ammonium chloride that maybe could crystallize in our lungs or somethings. Then when checking google, looks like chloramine vapor that is extremely dangerous and if excess ammoniia is present liquid hydrazine which is just as bad and potentially explosive also. https://www.buzzfeed.com/peggy/16-common-product-combinations-you-should-never-mix?utm_term=.xnr8r82bq#.xlQxPxRpQ

          Wow, I didn’t realize moral mushrooms have hydrazine toxins in them also. That stuff is also rocket fuel.

          1. Can not be completely correct. Bleach and an acid produces chlorine. But there is no Nitrogen in it to form chloramine. Although the latter is part of the swimming pool chlorine stink. There is a nitrogen source: pee (containing urea).
            They also warn not to drink red-bull and milk together, as the acid in the red bull would make the milk clump. Does the author not know about stomach acid?

          2. Huh, I thought the discussion was regarding ammonia and chlorine. Yes, pee from mice I am finding does do that especially on metal that is corroded as seems to be more ammonia smelling versus urine smell First hand dealing with at the moment… I mean pee stains and poo all over the place here in a few locations.

            Ammonia has nitrogen and hydrogen. I’ve never heard of anyone using acid and chlorine to clean. Usually, you use muratic acid which is HCl to etch or clean say concrete where I’ve used and am planning to use to clean growth and etch walls before re-finishing.

            I guess some previous generations used ammonia more to clean where I don’t recall anyone in my family ever using to clean. I had to beg to get when I was doing the silver plating and was thoroughly lectured on the dangers of.

            Like working with fire even, when I got the muratic acid in high school to etch the basement walls then… I had to make sure there was way open windows and fans for ventilation (first other than hoods review if HVAC where more in than out for pressure not backed up to assure flow), I had a mask with goggles, a face shield, gloves, adequate boots and PPE literally.

            The carbon can come in from cleaning, though not sure if alkylated or alkyl group in nature.

            The more I think about that time frame with a clearer mind and time to analyze more with post lean sigma tools… I am sure that is when the pedo gay community now acting more neuter targeted me to poison to be a scapegoat due to false pretense “smells like” what they were compounding and concealing with all their cocaine smugglers looking official with meth labs and other opiate junkies pandering and trafficking the community to death with all their stolen goods and tax fraud continuing criminal enterprises looking official.

  7. The Post Apocalyptic Inventor did a whole series about washing machine motors, of course he used more civilized european models(miele), something which would be considered luxuty/top of the line in US.
    wiring configurations, theory of operation, etc:

  8. “Using tools and materials in ways not intended or designed” is, at least in my opinion, the definition of a hack.
    Sure, the motor controller was intended to run that motor….*in that appliance.*
    Being able to arbitrarily drive the motor with any old function generator or microcontroller, is the hack…as one can now use the motors in ways not intended by the manufacture of the machine.
    But hey, to each their own I guess.

  9. Most large appliances such as stoves, washing machines, and dryers have at least basic schematics in a little envelope inside of them for repairmen. They usually have the motor pinouts on them, even if they aren’t specifically a detailed circuit diagram.

    1. Yes, this was in my old machine. Although the controller was not much more than a black box. this was a funny combination of a microprocessor together with a rotary drum switch system like in the old fashioned washing machine controllers. The latter seemed to be used instead a bunch of relays. Some fault codes were explained.
      All these did not help with the intermittent earth fault, which occurred. I tried to look for suspicious wires but did not find anything. Only when I completely disassembled the machine for parts salvage I found some suspicious molten plastic around the thermally activated door latch. But I did not really analyze this any more at this time.

  10. I’m curious what you can do with those motors instead of running them as motors. I guess there’s some decent wires spun inside, and a good bearing or two, but anything else usable?

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