What's inside of gearbox?


I’m particulary interested in 20 and 25D geared motors. Any chance to see what’s inside of gearboxes mounted on these motors? What type of material used for gearing and what kind of bearings?

I have tried a bunch of high torque DC motors but gearboxes in most of them have wear off in a very short period of time. Mostly because of materials used in gearing (brass, soft aluminium, plastic) and loose bearings.
The result of this is that the shaft become very sloppy in iddle, even up to 5 degrees free shaft movement, which is unacceptable for my application (I can afford max o 0.5 degree slopiness).


I bought two of their 25:1 20D motors. I don’t know in particular what type of materials they use but about the 0.5 degree sloppiness - from what I’ve experienced, there was more than 0.5 degree free shaft movement, even when the motors were new.

If you decide to try out those motors anyway you can completely unscrew the gearbox and see what’s inside.

What are you trying to do that you have those requirements?

Thanks for the reply.

I’m working with very precise equipment, so I don’t think I’ll use these motors. I got really cheap geared motor from eBay for testing recently and it has nearly zero slop on the shaft (I believe it will wear off soon, as I can see what the cogs are made of :smiley: ).

If these are sloppy as new, I don’t expect anything good from them in a long run unfortunately :-/
The only good, “affordable” gearboxes I found are made by Maxon, but I cannot afford them in quantity I need.
I’ll keep looking for alternatives anyway, thanks!

BTW. I’m asking here because a while ago We ordered a lot Pololu stepper drivers (DVR8825), We tested, incorporated in our project and there wasn’t even a single return :smiley: Well done!


Hello, Art.

Thank you for the kind words about our stepper motor drivers. We care a lot about quality, and it’s nice to hear when customers like you appreciate that!

The gears for our 20D and 25D metal gearmotors are made of steel, and only the output shaft has a bushing, which is an oil-embedded sleeve bearing.

If you are referring to backlash when you say slop, you can expect a couple degrees of backlash in those 20D and 25D gearmotors.