Z-Axis calibration problem

This is for general discussions. Also FAQ can be found here.

Moderator: speedake95

Post Reply
seaton
Posts: 291
Joined: Tue May 14, 2013 9:04 am
Location: Bunbury, Western Australia
Contact:

Z-Axis calibration problem

Post by seaton »

I'm having a problem with calibration of my Z-Axis, where over time its loosing accuracy.

going back on my notes

back in 4/3/2014 I was having some Z-Axis dimension errors so recalibrate then
result was

M92 Z1601.87731

Last night I re-checked as was again having some dimensional errors on this axis so I re-calibrated and is now

M92 Z1639.344262295088

which is quite a bit of drift over that period, and is drifting in the same direction

I'm calculating axis steps/mm by new steps = oldsteps * (50 / measured value)

I doubt it's the lead screw as it's not showing signs of wear, so the only other thing I can think of is my stepper motor.
Stephen...

Felix 2.0 -> Felix 3.0 dual
Simplify3D Slicer, Kisslicer
Have you added your Felix to the Map? http://goo.gl/maps/HajnZ

http://blog.strobotics.com.au

dognotdog
Posts: 181
Joined: Tue Sep 04, 2012 9:22 pm

Post by dognotdog »

Sounds to me like the motor coupling is slipping, maybe re-seat it and make sure the setscrew is tight.

Dreide
Posts: 176
Joined: Sun Sep 29, 2013 12:32 am
Location: Lausanne, Switzerland

Post by Dreide »

Why would you need to calibrate Z anyway, given that the pitch of the spindle is precise and constant over time? Even if there is wear, wouldn't that be all in the same direction and thus have no effect on Z scale? I rather guess that the Z motor is losing steps then and when. Maybe your spindle and rail need some renewal of lubrication.
Felix 2.0->3.0dual * Repetier (host+firmware) * KISSlicer Pro, Simplify3D * Cubify Design

User avatar
DDME-Marc
Posts: 71
Joined: Sun Nov 24, 2013 11:04 pm
Location: New Zealand

Post by DDME-Marc »

Hi Stephen,

I would agree with Dreide and suggest relubricating the slide and lead screw. I have used Super Lube (from Bilby CNC) with excellent reduction in friction. As a direct result I now run the Z axis at double the standard speed, with no increase in load on the motor. No sign of change in lubricity in the last 6 months.

Cheers,

Marc
Felix 3.0 Dual Head * E3D Titan V6 * Repetier-Host V2.1.3 * Repetier-Firmware 0.92.9 (01/08/17 - Modified) * KISSlicer Pro - 1.6.3 * Arduino 1.8.5 *

seaton
Posts: 291
Joined: Tue May 14, 2013 9:04 am
Location: Bunbury, Western Australia
Contact:

Post by seaton »

I checked the coupling, was firm, couldn't move it by hand but reseated and re-tightened anyway and now all working as it should, so looks like it was a loose coupling, not loose enough to move by hand, but enough to play havoc with the accuracy...
Stephen...

Felix 2.0 -> Felix 3.0 dual
Simplify3D Slicer, Kisslicer
Have you added your Felix to the Map? http://goo.gl/maps/HajnZ

http://blog.strobotics.com.au

Post Reply