jogging 3 axis works strange

Hi,
I am using 3 axis home build milling machine on steppers.
It runs on standard wizard configuration.

I have strange behaviour when jogging. The thing is when I want to jog 3 axis simultaneously sometimes only two of them move at a time, and sometimes all 3 go together.

Does anyone also had this kind of behaviour?
What can cause this.

Cris.

kmeld wrote: I have strange behaviour when jogging. The thing is when I want to jog 3 axis simultaneously sometimes only two of them move at a time, and sometimes all 3 go together.

Keyboard jogging?

This could potentially be the key rollover behaviour of your keyboard.

How are you jogging and with what GUI? Can you tell us how to reproduce the problem you see, using a sim configuration?

cradek wrote: How are you jogging and with what GUI? Can you tell us how to reproduce the problem you see, using a sim configuration?

I am using AXIS GUI.

I do not know how to reproduce problem with sim configuration. (I am not familiar with sim configuration). Bu also I cannot tell how to reproduce problem, in a stable way, with my configuration. This problem shows up randomly.

Yes this is happening when jogging with keyboard.
I use standard arrows and PgUp, PgDN keys. If I use combination of three not always all three axis move in the same time. But always at least two are moving. If this happens there is no difference if I press all the keys simultaneously or one by one. I believe only vertical (joint 2) axis is being switched off.
So if for example I jog X and Z in the same time and press arrow key to jog Y in the same time, Z stops moving. (But this is not happening always).
I am peaty sure that right after switching on and homing all 3 axis are moving together, and that this problem shows up after I run a program.

Cris.

Is it that the Z axis is stalling (motor stops but DRO keeps moving) or is it as if you stopped pressing the Z jog button? (I must say I've never tried to jog 3 axis simultaneously.)

Hi,
I did some observations and it seems than situation is as follows:
1) When Z axis stops also it stops in EMC, so behaviour is consistent with what EMC expects machine to do
2) Previously I thought that this behaviour was random but it appears it is not the case. Z axis is stopped for only one combination of X Y moving directions. So if I go X+ Y+ I cannot move Z in the same time. If I relics any of X or Y jogging key Z starts to move. It stoops expediently if I hold this combination of arrows.

Cris.

kmeld wrote: 2) Previously I thought that this behaviour was random but it appears it is not the case. Z axis is stopped for only one combination of X Y moving directions. So if I go X+ Y+ I cannot move Z in the same time. If I relics any of X or Y jogging key Z starts to move.

I think it is probably this:
en.wikipedia.org/wiki/Rollover_(key)#Key_jamming_and_ghosting

If it is your keyboard then you won't see the Z moves in this online key-event tester:
unixpapa.com/js/testkey.html

If you actually need to keyboard-jog 3 axes at the same time then you might need to find a keyboard that handles more rollover.