Which Stepper motor and which controller?


Still in research mode for my own CNC machine which will be Arduino based. But, as everyone is using different motors and controllers (drivers?), how do I choose the right one for me? My machine should be able to do soft materials like wood and plexi/acrylic but I als want to be able do mill/cut aluminum, as I am restoring an old car and parts are not easy to get hold off.

For my board I was thinking of an Arduino UNO (like most) but then, which motor to go for? Uni or bipolar? 17, 23, 34? And which driver? gShield / CNC Shield V3 / Dual step driver? A4988? 1 board per motor or can I combine them? How to get a smoother run then 1/8 steps?

(Found CNC Shield V3.0 + UNO R3 + 4pcs A4988 Driver for £15???)

I have never soldered anything, but I am a fast learner. So far when it comes to electronics, I managed to hardwire a stereo without harness into my car, speakers, radiator fan circuit and some door controlled LED's. Far away from soldering of building a CNC, but I am up for the challenge.

I know there are a lot of questions in this post, but I appreciate any explanation why someone chose one motor over the other etc.... Any information is highly appreciated. I rather research more then building something and then have to start over again.

Kind regards,


I was in the process of making a CNC(Assignment Writing Bot). Ran out of time before I could finish the 2nd & 3rd axes. Since my CNC didn't have a milling/drilling tool, I did not require motors with a lot of holding torque(almost no backlash). I used a Sparkfun EasyDriver and also their 15$ stepper motors.

Considering you want to mill & cut aluminum your probably going need motors with higher holding torque & a low stepping angle