Lathe Z axis/joint not homing after updating to 2.8

Hi guys,

In my attempt to use gmoccapy 3.x on my mill, I've updated to 2.8.
The mill software works fine, however when I try to home the lathe, the X axis homes fine, the Z axis does not home. If I click home axis again, it says "this joint is already homed". The homed icon does not appear near to the Z axis.
If i try to execute an MDI command it says that it cannot execute command while not homed.
Also the pendant does not seem to work anymore.

Here are my configs:
github.com/85vmh/LinuxCncConfigs/tree/master/configs/test_setup

There seems to be a fair bit missing from your config files as there are only 2 joints configured. (X & Z)

I think i would make a totally new config with pncconf that at least moves your axes. Then merge in your custom config from your existing files

Since its a lathe, its normal to be only x and z.
Is there something missing for these axis?

Sorry, you said mill in your first post so I missed the lathe part.

i have seen this behavior on a test lathe. i have not looked into it yet,I had another way to start the homing behavior - so I expect it's an AXIS problem.

Chris M

IN your ini file you seem to be missing coordinates= here so LinuxCNC can't map joints to axes.
I'm not sure if you can set this up using joints 0 and 2 as you have as that line maps the axes to the joints so I suspect you may need to move your Z axis to joint 1. I have not looked at the syntax to skip one (ie X?Z) so you need to check the docs before you hack into the wiring.

It seems from the docs you can't use joint 2 without a joint 1
linuxcnc.org/docs/devel/html/config/ini-...g.html#_traj_section

I wonder if this was thought about when the joint axes code was added?

In the ini file you have axis = 3 but you only have X and Z !!

rodw wrote:

It seems from the docs you can't use joint 2 without a joint 1
linuxcnc.org/docs/devel/html/config/ini-...g.html#_traj_section

I wonder if this was thought about when the joint axes code was added?

What I mean by this comment is that this potentially will break any lathe config when its automatically converted to V2.8 which moves from fixed mapping between joints and axes to independent axes as there is no method to skip a joint in the kinematics statement.
Seems like we need to support something likein the coordinates string so the existing config works correctly as I don't think you can reorder the stepgens on a Mesa card.

Clive wrote:

In the ini file you have axis = 3 but you only have X and Z !!

This is part of the problem, potentially a bug (or at least an undesirable feature). He needs 3 axes to get a joint 2 to suit his hardware but he can't tell his config to use stepgen2 so he has to move his motors to stepgen 1 as it stands now.