How to determine what stepper motors will work with my board?

I am looking at upgrading one or both of the stepper motors on my Atomstack A10 (X7 Pro) and I’m wondering how much power my board is capable of outputting.
It has the Laserbox ESP32 V1.0 board

As far as I can tell the drivers are built right into the board, the red and blue connectors along the top go straight to the stepper motors.
The current motors are labeled 42bygh34h y 27d
Are there any other considerations other than the amp rating and the nema size? (Nema 17)

I couldn’t find much on that board, do you have a schematic or link?

What do you intend to accomplish by a motor change?

If you go with larger NEMA motors you will have to figure out how to mount the motor and pulley. Doubt they will fit without some kind of modifications.

Good luck


I’m hoping stronger motors will able to handle having the wheels tighter to avoid wobbles without skipping steps. I know I need to stick to Nema17 motors, but there is a considerable range of those motors, some with more torque than the built-in ones.

Would it even make sense that the stepper drivers are built into the motherboard? Perhaps the heatsinks above the label?

Unfortunately they are not really the ‘same’ size. One of the dimensions is different. It is the ‘L’ distance in this pdf.

Data-Sheet-Stepper-Motor-Support.pdf.txt (839.0 KB) you need to remove the ‘.txt’

You don’t get extra ‘power’ without some kind of tradeoff. Here are the specs for the NEMA 17 motors…

The higher the power or torque the ‘thicker’ the motor.

It will mount ok as far as hole location, but it’s ‘butt’ needs more room. The mounted rated current is the same for all of them, at least the data sheet says so…

If the current is the same and they will physically fit, should be ok…

Mine are separate hardware. I’m pretty sure your stepper drivers are probably on board. Much more expensive to have separate ‘modules’.

IMHO, this is not what you want. You want ‘smooth’ mechanical mechanism that will be a even load to the motor. Many things fail from being too tight.

The ‘wheels’ have a designed ‘weight’ to work properly. Can’t just tighten them up and make up with extra power. Many of these wheels will actually ‘dent’ (get a flat) if it sits unused. They they would have to be replaced.

Good luck


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I can’t seem to open the data sheet provided in this thread. I’m looking to know what the specs are for the motors mentioned by the OP?

My intent is to have a rotary from Atomstack or xtool and use it on my large CNC but need to know what stepper driver would be appropriate for this task.

Motor is stamped with 42bygh34h-y-27d. I believe it’s 12volt (not sure that really matters). But would like to know the amperage rating so I don’t fry it.

Did you remove the ‘.txt’ extension? We can’t upload some file types, so you can append the ‘.txt’ extension and upload it… The person that downloads it has to remove the extension.

This is my google drive link to the pdf

Measure the size of the motors… NEMA15 are 1.5" a side … NEMA24 are 2.4" on a side.


Old thread, but the board says ‘2A max’ but that’s everything all at once. The lowest amp NEMA 23 motor I could find was 2 amps. Right off the top, I knew it wasn’t going to work.
However, I’m not ‘that’ guy…so I swapped out the much larger NEMA 23 that came with my chinesium chucked rotary, and put the 2amp NEMA 23 in. It will spin the rotary, but there is little ‘control’ available with it as it’ll spin, but won’t stop with the inertia of the large metal chuck. Even direction changes, not enough power to stop the motor and start the other direction. Several times I lost all controllability with the board, and had to do a hard reset to get it to do anything at all. It wasn’t even worth the time going any further with the stock board.
That said, I’m working on a replacement system using 4amp drivers on 5 axis. Plug and play with the existing NEMA 17’s on the stock X7 Pro system with the added “A” axis if I want it. It also gives me the option of canning the entire existing 2020 aluminum 18"x30"framework and moving up to the intended 3’x5’ 2080 frame I’m building to handle full size guitars.
So, no, you probably won’t get much love out of a NEMA 23 on the stock X7 board.