Very powerful gearbox from wiper motor.

[manshands]

Very powerful gearbox, from wiper motor and gearbox angle grinder. Drawings are on all my videos.

[Crusty]

The wiper motors that I've taken apart have no need for a shear pin to protect the connected equipment because the plastic gear in the wiper head protects any metal shear pin inline. Still, wiper motors deliver enough torque and are durable enough to be useful for projects and I have one powering the table power feed on my benchtop milling machine.

There are typically three brushes in the motor (common, high speed, low speed) and the common is connected to the housing which in turn connects to the negative power terminal, but if that brush is isolated from the housing then power can be applied between the low speed and the high speed brushes (in reversed polarity) and a third and fastest speed results. A 6 position, 3 gang rotary switch is then all that's required for 3 speeds in each direction. Not all wiper motors are created equal though so further investigation is required for a particular motor.

[manshands]

This engine is from the "Great Wall Deer" car. I tried different contacts and wanted to find high and low speeds, but unfortunately I found only one speed. When connected to other contacts, the engine rotates at the same speed, but with stops at full revolution. I have two different engines and in both engines only one speed and rotation with a stop.

[Jon]

This engine is from the "Great Wall Deer" car.

https://en.wikipedia.org/wiki/Great_Wall_Deer

[DIYSwede]

Given the low rev when under load, the flimsy app. 5 m long 0.75 mm2 / AWG 18 cable acted as an efficient current limiter,
against blowing the cigarette outlet's 20 A fuse, not even close of even stripping the plastic gear...
Guess the motor just received some 8 VDC & the cable became luke-warm during that test too?

My personal favorite in this area is the KSV 5035:


I've had one of these "600"-flavor mothers jam to a stop at 24 VDC & >20 A* in without shredding the Acetal 49:1 worm gear.
They've ripped frozen, stuck windshield wiper blades and arms to shreds over here since the fifties in cars, trucks and buses.
Wire feeder motors in industry grade ESAB and Kemppi welders since the seventies.

I salvage these from discarded heavy-duty office table pillars at work: +150 kg cast iron on the table: 2"/ sec raise w/o trouble at 18V in.
Made for 100% duty, -20 C Nordic weather, works for decades and they'll take anything below 50 volts and just run.
Haven't fried one yet, their magnets haven't even come close to their Curie points, and they take no prisoners without complaining.

Shortest possible length of 2,5 mm 2/AWG 14 minimum and big-amp DC supplies or SLA batteries in my builds too,
just to get that "no bull" starting torque and as stable rpm/ volt independent of loading I can get.



Just my 2 cents & YMMV

Johan

* My clamp DC ammeter simply maxed out at 20A in that test.

[manshands]

Unfortunately, I found it in my workshop, only a cable of 0.75 mm2 / AWG 18. It was really long and heated up very much after lifting the machine. The wiper motor has also warmed up. Unfortunately, I did not measure the current consumption at load, the engine power is 20 watts.
I tried to connect a wiper motor to the jack without a gearbox from the angle grinder - it does not work at all.
I want to try to connect this design not to the cigarette lighter, but directly to the car battery and increase the wire cross-section.
Thank you very much for recommending the KSV 5035 engine, I will try to find it and it will participate in my experiments.

[DIYSwede]

It was really long and heated up very much after lifting the machine.
Unfortunately, I did not measure the current consumption at load, the engine power is 20 watts.
Thank you very much for recommending the KSV 5035 engine, I will try to find it and it will participate in my experiments.

Yup - short, coarse cable is the way to go if you want some work done at the motor end, rather than just a cable heater.

Is the wiper motor rated at only 20W? Are you sure? It should be at least 100W in continous duty -
then it can be (temporarily!) be overloaded some 300% without ill effects.

I doubt you'll find any Ankarsrum geared motor over at your place -
best and cheapest bet (as always!) is to go to a scrap yard
and get any biggie 24 V wiper motor from a full-size truck or bus.
Bring at least an ohm-meter for checking it, better still is a small 12 V SLA battery in your rucksack.

Good luck and keep up the good work!

Cheers

Johan

[manshands]

Yes, a motor with very little power. According to the manufacturer, 20 watts.
The very meaning of the experiment was to use a low-power motor in combination with a angle grinder.
Based on this gearbox, I’ll do the next project very soon. I will try to achieve a pulling force of at least 100 kg.
Thank you very much for the advice, it will help me a lot in future projects.

[JoeH]

I've been looking at this motor recently. Looks similar to the ones you guys have been talking about.

https://www.amazon.com/Makermotor-Sh...5D9XSMS76RBJW3

[DIYSwede]

I've been looking at this motor recently. Looks similar to the ones you guys have been talking about.

Sure its similar - but smaller in size with a 50 max rpm and 60w continous output -
the page doesn't say anything about the duty factor for higher outtakes.

Its non-cheap price tag and "Makermotor" brand sounds to me like it's intended for the Arduino lot/ Robot making crowd.
A (no-load) 50 rpm motor with 4,4 ft-lb starting torque will eventually get the jack up,
but it'll take some time and probably complain a bit when the fully loaded scissor is at its bottom,
where the screw, nut and its bearings is at its highest stress and the jack has its max lift/ turn.
For the cost of this Makermotor alone you could get a 2 times as powerful, complete electric scissor jack at a FleaBay discount,
but then you wouldn't have a DIY project...

Added: Most 2,5 ton electric jacks available of FleaBay etc has a 100-120W motor and a 15 A fuse -
giving a max momentary input power of 200 W.
I've found none of these listing the full height & load lifting time (nor the motor's rpm),
but a few reviews state "within a few minutes"...
If you choose a low watt & lo rev DIY solution - there's simply a time penalty to pay for any given load,
(if it'll work at all) as there's simply no free lunches here either.

YMMV - Personally I'd rather visit the local scrap yard for a heavy duty hi-tork piece with 200-300-ish rpm for a mere 10 bucks.

Cheers

Johan