Z-Axis indicators not matching at top

Hi,

At Z=0 my two Z-Axis indicators align to the rods correctly, and repeatably, but when Z is at Home they are approximately 180 degrees displaced.

As the motors are series driven and everything is OK at Z=0 I do not believe this is a missing-steps or mechanical tightness issue. Is this caused by slightly differing thread pitch on the two rods?

Regards,
Neil Darlow

---

I try to write with consideration for all nationalities. Please let me know if something is unclear.
Printing with Mendel90 from fedora 25 using Cura, FreeCAD, MeshLab, OpenSCAD, Skeinforge and Slic3r tools.

The idea of the indicators is to point them at the rods when the machine is homed, not at the origin.

They should both rotate in synchrony, regardless of thread pitch, because they are wired together. When pointed at the rods they are 180 degrees apart because the rods are on the left or the right of the motor. That means the pointers should always be 180 apart, but only point at the rods every 1mm travelled.

---

[www.hydraraptor.blogspot.com]

Ah, that makes sense. Thank you.

---

I try to write with consideration for all nationalities. Please let me know if something is unclear.
Printing with Mendel90 from fedora 25 using Cura, FreeCAD, MeshLab, OpenSCAD, Skeinforge and Slic3r tools.