I'm currently trying to build a CNC engraving machine. We decided to use Arduino because of its low initial investment and the opportunity to learn wiring/circuit design.

We're researching what power motors we can use with the Arduino and Gshield expansion board. I initially ordered these motors (https://www.oyostepper.es/goods-77-Motor-paso-a-paso-Nema-23-bipolar-18-grados-19-Nm-28-A-32-V-57x57x76mm-4-cables.html).

They are rated at 2.8 amps, while the Gshield is rated at 2.5 amps. I'm finding a lot of information that seems contradictory and I'm unsure if they will work properly or burn out the Gshield.

Does anyone know which motors I should use, or how to calculate which motors will work correctly? I want to use the highest power motors that are perfectly compatible with this Gshield.

 

Having already purchased the Gshield and the motors I’d suggest building the engraver with what you have, putting resistors in series with the motor windings to reduce the current. You’ll be wasting power and losing torque but saving money! For an engraver I think you would need fairly slow movements when actually engraving so I would have started with much smaller lower current geared stepper motors and used low cost H bridge ICs with 1A current capacity

 

I'm not familiar with the GShield, does it have on board motor drivers or are they separate items. If on board, do they have settable current control?

 

Where did you get the info that you would need NEMA 23 Motors?
For an engraver. I would have thought that something in the NEMA 17 range should have sufficed? !

 

,,,,,,,,,,,,,Or even:-
Qty - 3 /CAN $43

 

The first question is, How big is this CNC going to be?
The next question is, Do you know that you can buy a CNC3018 for less than US$50 ?

https://www.aliexpress.com/item/1005009354631413.html

One good news is, I am using a CNC3018 for engraving copper clad circuit boards. It does a beautiful job.

 

The next question is, Do you know that you can buy a CNC3018 for less than US$50 ?
https://www.aliexpress.com/item/1005009354631413.html

I find those Aliexpress ads misleading.
That price appears to be just for the controller; once you click on the machine itself , the price goes up dramatically??

 

I find those Aliexpress ads misleading.
That price appears to be just for the controller; once you click on the machine itself , the price goes up dramatically??

Yes, you are right. Oftentimes, the price shown is for a different model or even just a component and not the complete system.