Hello,
I discovered this project a few weeks ago and I finally think I have the cnc of my dreams!
thank you !
I am planning my project and for that i want to use the motors from my old 3d printer.
the characteristics are: NEMA 17 1.8° and 39mm TB42HT39-1684AC - Holding Torque 3,6 kg·cm.
Are they powerful enough ?
what maximum width for my axes with this type of motor ?
Have a good day and happy new year from the Basque country
The second picture on Ryan‘s shop has the detailed specs: Nema 17 84OZ/in Steppers – V1 Engineering Inc
I‘d just compare those. 
Your steppers seem underpowered to me. For your comparison, your steppers are 51oz.in. Ryan sells 84oz.in steppers. I didn’t spot a minimum holding torque spec in the LR parts list, but, if I remember correctly, Ryan specified 55oz.in as a minimum for the old Burly machine, and I imagine the LR would have at least this minimum.
I noticed that my old steppers are below recommendations
but I thought that if I reduced the width (X axis) and therefore the weight, I could use my motor and save some money…
Not really worth the hassle. Changing the motors shouldn’t it work takes quite a while.
I built one with those motors and it works fine. You just need the newer yz plates that have the wire connector cutout. You may need to slow your accelerations to avoid skipping steps.
@orob thank you for the details.
I will try with my steppers following your advice.
Here we go!