Stepper driver/motor question

Why 1600?
What would happen if they were all changed to something higher?
I have all high power drivers now and noticed the other settings but haven’t been able to find anything about it other than the directive to do it this way.

Can anyone point me to the specs for the motors? I’d like to at least see what the current ratings are.


The stepper configuration is hardcoded in CutControl. If you changed the steppers to 800 everything would move twice as far as it should, and if you switched them to 3200 then they’d move half as far ans half as fast. You really can’t change it unless you want to swap the control system (which is a very valuable upgrade in my view).

The motors are branded at Langmuir. I would just take good measurements and assume they have specs identical to motors with the same measurements at Stepper Online. I can’t guarantee that this is safe option.

Thanks for the insight!

Could you comment more on the control system swap?

Search for a thread started by me with the title “LinuxCNC”. You’ll find lots of details there.

I also wrote up more about what I did at GitHub - alexphredorg/mr1: Langmuir MR-1 configuration for LinuxCNC

Also look for threads by Ryan Reed on the FB group or here under MrMachineTx. He’s also posting some new youtube videos.

A recent video of my machine running under LinuxCNC is on youtube here:

Very cool. I envy the pneumatic tool holder.
Would you say that any of your changes improved threadmilling resolution, or is that purely an issue with Fusion360?

Thanks for the info.

I’ve only done limited threadmilling, and at fairly coarse threads like 1/4-20 and M5-0.8. What are the issues that you run into?

The only resolution improvement that I could easily get would be by changing Z stepper to something with finer steps (or maybe changing microstepping, but that doesn’t normally achieve real resolution). Today I’m using Langmuir’s stock stepper motors, but improved drivers, running at the same microstepping.

This is a piece I recently milled out of mild steel. The thread is 7/8 - 28. I used this threadmill from Harvey.

.025 finished thread depth at .005 per pass

Could be a feed/speed issue but Fusion has no adjustment for resolution of the interpolation of the tool path for threading, like it does for other processes, so it seems plausible that the issue could be related to a limitation induced by not enough steps/rev in the steppers.

That doesn’t look terrible to me, but I’m also a hobbyist who may have low standard. At a risk of tool wear I wonder if a spring pass at half the feed rate but maintaining same spindle rpm would clean it up.

I see no issues with that thread either. The setting that would affect the tool path you’re thinking of is called “approximate arcs with lines” in SolidCAM and lets you chose how long the individual linds end up being. If that setting is enabled and too course it will create faceting. I’m not sure if 360 has a similar setting but I don’t see that happening in the example posted.

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If you’re really hard-core looking for that formed thread finish, can machine an undersized thread start and finish with a tap.