Need some help finding a DC motor

Hey so what’s a community good for if you can’t ask for help?

I have these adjustable tables now that can change height with a hand crank…

I want to replace the crank with a little simple electric motor that can bottom out without causing too much torque on the table mechanism… no motor controllers, just a simple DC motor with decent mount and hopefully a hex shaft. The hex shaft is 9.8mm;

The center of the shaft from the bottom of the table, presumably where I’d mount the motor to, is 25mm;

Any ideas welcome :slight_smile:

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You may wanna think in non metric units. 9.8MM is odd as hell, but if you convert it to inches, it’s .385"

That’s just too close to a common hex size, 3/8" is .375 in decimal inches.

You’ll probably have better luck looking for that.

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Oddly close to one inch, too, as a follow-on from that 3/8th shaft.

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Having a hard time posting as I miss posted it earlier.

Apparently 3/8 hex is a thing in hobby robotics. Seems to be mostly gearbox related though.

Watch the video at this link

Also this double motor gearbox.

Think I found it.

Gearbox Reduction: 26.9:1
No Load Free Speed: 198 RPM
Stall Torque: 6.3 ft-lbf
Minimum Backdrive Torque: 0.3 ft-lbs

Here’s the LINK.

Select the 27:1 ratio, with 3/8 shaft, no encoder.
65.00 dollars.

Roughly looks like it’ll fit the 25mm dimension. Has CAD drawings to confirm. Lots of mounting options.



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Am I the only one to go poking around in the out of focus background hoping for an unplanned cool-o reveal of futuretech?


3/8" is a common hex power bit size, and is found labeled as such even in the metric world. But for those who insist on metric, that’s 10 mm. Tolerances are loose enough for the two to be interchangeable.

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Almost happened… it’s currently glued to this card :wink:

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Alright, I’ll bite :fishing_pole_and_fish:

You mean the “minority” 95% of the world as you well know Rosco, ya stirrer.

Um, need I point you toward
3/8ths… what a ridiculous measurement.

let’s break this thing down into 8
but that thing should be separated to 32…
Man, that is some backward shit.

how about making it decimal… oh wait, you did
so 3/8ths is .375 in decimal inches. WTF

Pretty sure it was either Ford or Johnson ( which ever was in the 70s) tried to get you lot using metric, I hope your new president enforces it… maybe not the number one priority to fix, but come on ready, you’ve had ~50 years to adjust


Totally agree. This 31/64" socket didn’t fit. Anybody got a 63/128" laying around? Tablespoons and teaspoons can fuck right off. If we left the tea in that harbor in Boston, we should’ve dumped the spoons too.

I would be fine with the US going full metric. I try to get by with metric only tools. Although, I drive a European car and work on Japanese cars so metric is perfect for those applications. The only area I struggle with is identifying temperatures. I can walk outside and say “It feels about X degrees [Fahrenheit] today”, but I can’t really do the same with Celsius. Just need to get used to it I guess.


Well, you can have one idiot using standard, and 99 others in a room who insist on using metric. There’s no contradiction in terms between being a majority and insisting that the minority step in line.

As of “stirring” anything, unlike some of you who seem bizarrely upset by the use of non-metric units, I have no emotional attachment to metrological things. People who might think I’m yanking their chain really need to latch onto another, less inconsequential issue :slight_smile:

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He’s busy making America great again atm. Metrication is next on his agenda.

If he actually was, He has a head start, US Medical and Military already use it…

I worked with various branches of the US military, and that is far from being the case.

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Other than aircraft and vessels speed in knots and height in feet I concur, other than that, I guess we will agree to disagree on that one

Comprar Kit motorización SkyWatcher DMD-EQ5 para EQ5 y NEQ5 y con puerto ST4 de autoguiado Online

President Carter, I think.

I will just point out that the solution was found in imperial units, not metricity. :wink:

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I think you mean standard. Imperial == UK - definitely a stupid, antiquated unit system :slight_smile: