Upgrading stepper motor for 80mm Spindle

@alldaysammyj have you been able to make any cuts with the new setup and also curious if you are noticing any loss of detail or speed issues during the cut?
Second does the added microstepping add significant time to your projects?

That, my friend, was hilarious! :rofl:

Hey,

unfortunately you posted a link to a closed-web, members-only resource. Can you upload it to a public webspace?

Thanks,

Hey Mike,

loosing detail on the work after a spindle upgrade like this is surely not the result one awaits or hopes for! I find this a little bit worrying. I am sure it’s not just me who would like you to investigate this.

There could be different error causes.

I’m with you questioning whether some components of the Z Axis Gantry and Mount could be overburden, including stepper motor. But before suspecting one of the Onefinity’s components I would make sure that everything is in order with your spindle and with your tool. Can you check true running, first at spindle axle, and then at tool shank, using a dial gauge like explained in this video?

Btw, do you have X-35, X-35 with “stiffy”, or X-50 Rails?

Thanks,

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I have the x35 with stiffy rail currently. I could try that possibly with the gauge however I don’t think there is wobble from side to side in the spindle. It looks to be up and down movements that are out of detail in the very fine details. I will keep working on it when I can, but I’m not technical in the troubleshooting field. I’m new to cnc and may just put the original spindle on that had no issues until some other upgrades are also available.
Thanks

A stepper motor usually does not struggle for life. If it has to move against a force that is too high, it looses steps. The controller has the ability to recognize that.

Also Onefinity stated here that a heavy spindle using 80 mm mount would be no problem. The 80 mm mount has not been released without longer testing.

I would suspect that there is some backlash/clearance somewhere.

What spindle do you use?

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This could be a hint for axial clearance, i. e. in the spindle axle. Bearing clearance can be radial but axial as well. You could measure it by pushing the axle into the spindle, with the dial gauge on it.

You are using the 80 mm mount, right? Did you check the bolts on the Z Axis’ ball nut, and those on the ball screw coupler too?

Anyway if you bought a spindle I would not give up that quickly. The loss of detail is not normal. And you also mentioned the advantages. Speed, and no ugly noise of sparks-emitting carbon-brush commutators on the home handyman’s consumer hand router…

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I would look at the spindle mount since you had to remove the 65mm mount and replace it with the 80mm. Mainly the lead screw to make sure there’s no play in it. The collar that clamps to the screw itself

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I will look into it thanks for the tip

Yes I used the 80 mm mount G penny 2.2 kw spindle. I will go over the details you mention where I can. Wondering if you think the nema 23 on the z is rated for a 15 pound spindle? Ive been told it is not, I understand onefinity did a lot of testing and state it is not an issue. I am also not doubting it could be something on my end either.
Thanks for the help

I am not sure how much you enjoy math, but here is a great video - Calculating Lead Screw Efficiency and Required Lifting Torque - YouTube - which shows the calculations for lead screw efficiency and lifting torque. The mass lifted and lead screw parameters used in the video differ from those on the 1F with your proposed 80 mm spindle. However with a ‘little’ math and the correct 1F leadscrew and spindle mass data, you should be able to calculate the stepper motor torque required to lift the spindle.

If you are still not daunted, Bosch Rexroth offers free configuration software for their products (but easily applicable and effective for any application). It is highly configurable and gives a great deal of information for those looking to size motors for their machines. Here is a video walk through of how to use it and some of the data it generates - How to Size Stepper Motors For A CNC Machine | .

The resulting data calculated from either of these above options may put your mind at ease as to the suitability of the current 1F stepper with your 80mm spindle.

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Well I’m interested to see what happens with incremental upgrades.

I previously used a Shapeoko with a 2.2kw 80mm spindle so feel like the 1F should be able to manage it…

We’ll see.

Right now my problem is that the two set screws in the bottom of my z-Axis stripped (I had a brand new high quality hex wrench but I think they were just a little over torqued). Have to get these out and swap my new 80 mm mount in before I can do more testing.

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The 2 small set screws on the bottom do not need to be removed in order to change the spindle mount.

Hi
Did changing the micro steps in the z help or did you notice any changes from doing this? Wondering if I need to do this?
Thanks

Honestly I haven’t noticed much benefit from increasing the microscopes in the Z direction. I have found more benefit on the X and Y plane.

Have you noticed any loss in detail with the larger spindle?

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No loss in detail that I can tell. I milled out some wood parts that mate up to the aluminum parts I made and everything went together just the same as is did with my 800 watt spindle. Reading through this thread there are a lot of thoughts going on but as I said earlier fellas, IN STOCK FORM THIS MACHINE HANDLES THE 2.2KW SPINDLE JUST FINE :+1:. 60-80 IPM is what I mill most of my parts at and this includes a lot of adaptive, boring and contour strategies.

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Just finished milling this new fixture plate. 2.2KW spindle, stock steppers all around…and very accurate. Finish is smooth as silk. I hope this answers some questions :+1:




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Update:

Have the spindle and big@ss™ stepper installed (still have to tram the spindle) and all looks fine so far.

Wired up spindle with breakout box and now have full spindle control via gcode.



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Um, Dave?

The third step in the video you linked showed the exact two set screws I stripped as needing to be removed.

Ended up having to drill them out and it looks like they had some kind of thread locker on them.

Luckily I was able to remove them without stripping the threads and had some replacement set screws and all is well.