Stepper motor and driver details

I wanted to know what type of Nema 23 stepper motors are being used on the CNC, specifically their torque rating. Also, since the Onefinity controller is based on that created by Buildbotics, would the stepper drivers be the same as those in their controller?

I’m also curious as to the motor size. They almost look identical in size to the 140’s I had on my x-carve, which never gave me a bit of trouble.

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Mine has a label on z axis that says 2.8amps, 1.2Nm. Part number 23HS22-2804S. Can’t see the X or Y motors at the moment (or likely ever until I move it again ;)) but they look to be the same size.

-Tom

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Good info, thank you for that!

Thank you for the information.
I am considering purchasing the ‘Woodworker’ and therefore looking to find specs like this that are not readily advertised. I am sure the engineers at Onefinity have determined that these motors are sized appropriately for these CNCs (They certainly are affordable). I must admit however I am a little disappointed in that these appear to be some of the least expensive stepper motors I have seen, and given that the controller and machine hardware appear to be able to handle better motors (i.e., more torque, etc…) I would have thought different motors would have been chosen for such a well built and designed machine.

I will say I have very little experience with CNC machines, so I am hopeful that the online experts will set me straight, and let me know these are more than capable.

While I don’t yet have my machine, I have seen post after post after post of people who have more experience with CNC woodworking than myself sing the praises of this machine. I have never heard anyone complain about the available jog speed or power of the machine. You are correct in that there appears to be plenty of reserve power from the controller for larger steppers, but it doesn’t appear they are really necessary.

I agree, as that is what I have seen through videos, and heard as well. I am really excited about getting one - still need to save a bit more in my tool fund - as it looks to be a very well designed and constructed CNC. As a Canadian, I am especially proud that this is a ‘homegrown’ product, and it means a lot to me personally to be able to support this new company. They seem very active and responsive to the forum members’ comments and suggestions, which from my experience is a very good sign.
Thank you for your thoughts.

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You’re absolutely correct on that, they are very much “in the trenches” with the users, getting feedback and finding out potential issues. Very impressive.

As a machinist & tool designer, it is absolutely a very well designed machine. It’s the only one I’ve run across that prompted me to sell my totally modified x-carve & wait till December.

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I have had the Woodworker since late September. I also questioned the stepper motor size choice made by OneFinity when I was setting up the machine. I have built several custom cnc’s for customers and have larger, more powerful motors that are still in boxes waiting on a machine to put them on. However after a lot of use, I have yet to experience any stalls or motor issues at all. I believe that OneFinity got it right! So my recommendation is save your $ for something other than upgrading stepper motors.

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That’s the beauty of the Onefinity, there appears to be very little, if any, ‘required’ upgrading, although I do have a couple ideas in my back pocket.

I wonder whether the use of ball screws means that smaller stepper motors with lower torque can be used. There are other hobby CNCs that I have been looking at (i.e., Mega V) that opt to use rack and pinion, and they seem to use motors with higher specs, so maybe it matches the mechanics of these machines better.
I have been reading about the advantages and disadvantages of different linear motion systems - there is a lot of information and many different opinions since there sees to be so many factors at play - and it seems that for the size of the Onefinity machines the ball screw is a good choice for all axes.

Indeed it is a good choice, as well as beefy round linear rails. Many machines use sq. linear rails, but they are more prone to contamination. Additionally, their assembly typically onto aluminum extrusion frames, while good, is still prone to misalignment during assembly. As I’ve preached many times on here, fewer assembly components generally = a better design, better accuracy, and less maintenance (less to initially be assembled wrong, or get out of whack after time).

That is a good point. With some of the other choices out there I would need to factor in the cost of my time to assemble, as well as the cost of a litre of Loctite for all the machine screws used.

@TMToronto - the drive system for CNC’s is a bit of a religious ‘war’. In short, Rack and Pinion can scale to essentially any size. That’s why you seem them on large industrial machines. However, to get accuracy and precision with R&P, the gears have to be exceptionally well machined and very high quality. That makes them very expensive. On the flip side, you can get high quality screw drives at a lower cost with exceptional precision and accuracy. However, their length is limited before backlash becomes a significant issue. Or at least that is what I discovered during my research.

I plan to do a number of tests on the OF once I get things tuned. I’ll report my findings for consideration.

-Tom

I would appreciate that. Like many things, the quality of the components becomes important and sometimes a limiting factor. I will trust that in their design and manufacture the OF engineers chose the ball screw system (not sure which Class is used) that gave the best performance for this CNCs intended use, balanced with an appropriate price point and profit margin.

Could someone confirm that the Z axis stepper motor being used is still the Nema 23 Bipolar 1.8deg 1.26Nm (178.4oz.in) 2.8A 2.5V 57x57x56mm ..., and if the same motors are being used for the X and Y axes.

Thank you.

I can confirm that is what I have - I have no clue what is currently shipping but I don’t suspect they changed the motors. 0.02.

-Tom

Thank you for taking the time to confirm this - I appreciate it.