Anyone running the M2 ( Arduino Due) with the Meticulous Z axis ? ( the wooden one, not the metal M2 Z Axis)

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Anyone running the M2 ( Arduino Due) with the Meticulous Z axis ? ( the wooden one, not the metal M2 Z Axis)

I’m having a hell of time calibrating the Z.

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I’m running one with a metal sled with the same z pitch as the meticulous, but with a different motor. I had to " tune " the pid to get it to work. “Tune” means that it was an iterative approach, not a mathematical one. Initially there was crazy overshoot with the movement, but it is dialed in now

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Thanks for the reply ! care to share your process ? I’m stumped.

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what gear ratio is used on your meticulus z. A lot of people used 3:1 (60T to 20T)
While the M2 uses 2:1 ratio. might be easier to just swap the two gears to make it the same?

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Thanks for the reply,

I believe you’re right, I’m at a 3:1

It’d be an easy change for sure, but I’m not sure that would make things any different.

I’m certainly not familiar enough with all of the math to say it will or won’t work.

I think it all boils down to the M2 calibration widget. which doesn’t seem accurate at all. The reason I am fixated on this is because in my experience, it seems broken.

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I’m using a faster 100 rpm instead of the 10rpm motor so it is actually 1:2-something. I don’t have it in front of me, but I can share the process I used with you to get it dialed in. Most important was my caliper that I used to measure the movement on the linear bearing slide… Over and over again. You must change the mm per step or per pulse because unlike the “control” software that broke out an axis pitch, the math includes everything from the encoders to the spinning shaft, so there is only one number to change and it is a weird number because it factors in the motor gear ratio, the pulses per step, steps per rev, belt ratio, and shaft pitch. Hopefully you won’t need to change the pid values, but if it is needed, you can.

Edit: $102 = 918.75 is the std setting for the M2. with a pitch of 8. If you ahve a pitch of 24, try dividing by 3 at first glance.

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Thanks for this. I need to double check that $102

It’s definitely still at default.

Funny how they just assumed everybody using the Due board was going to use this f’ing M2 metal sled. Really irks me.

If you could send me the links for the motor you use that would be great. My pulley has a little bit of slop on the existing motor shaft, so maybe that’s part of my problem.

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There’s a good calibration procedure in the meticulous z axis documents that worked well for me. I recommend using a digital micrometer (harbor freight has these, but get the larger one) to measure expected vs actual movement; I was able to get mine to within .25mm using this approach.

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I have a good caliper set. That’s how I know how off it is.