Weird micro-step issue

Discussion of linuxCNC (formerly knows as EMC2)
Post Reply
DarkApollo
Posts: 25
Joined: Mon Jan 13, 2014 1:53 pm
Location: Carlisle PA

Weird micro-step issue

Post by DarkApollo » Sun Sep 21, 2014 3:58 pm

I finally got my S2 back up and running after a complete rebuild trying to trouble shoot the Z-Axis jittery movement.
My controller is an MX3660 and I am running LinuxCNC. I have the controller set to ~2A PWM and 16000 micro steps (x8 stepping @ 200 steps)
HOWEVER If I set the microsteps in the LinuxCNC set up to x8, the X and Y axis lock up but the Z axis runs perfect. If I leave the controller at x8 but put x2 in the set up the X and Y move smoothy and fluently. If I change the controller to x2 on those two axis, the X and Y lock up and get jittery. This is obviously messing with the scale..
Thoughts? Ideas?

cvoinescu
Posts: 4442
Joined: Thu Jul 19, 2012 6:50 pm
Location: Camberley, UK
Contact:

Re: Weird micro-step issue

Post by cvoinescu » Sun Sep 21, 2014 9:49 pm

This may sound obvious, but 8 times 200 is 1,600, not 16,000. :)

What you see could mean that you're trying to move the X and Y axes too fast. If it works with the driver at 8x and LinuxCNC at 2x, then try reducing both the speed and the acceleration to a quarter of what they are now, change the microstepping so that the driver and the configuration of LinuxCNC agree, and it should still work, moving at the same speed.
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

DarkApollo
Posts: 25
Joined: Mon Jan 13, 2014 1:53 pm
Location: Carlisle PA

Re: Weird micro-step issue

Post by DarkApollo » Mon Sep 22, 2014 3:24 pm

Correct, I meant 1600 not 16000

I will mess with the acceleration and travel speeds to see what effect that would have. Thanks.

Post Reply