I have MPCNC set using dual endstops, they work fine.
To my understanding I need to find zero level of Z axis every time I print due to changing bit, moving Z
between session and so on. So I need to activate Z homing, get Z moving down until the bit touches the plate - then it knows material top or bed bottom or whatever refference point from which it can find where to start routing form.
So, I click Z home and Z axis moves 1-2 mm down then stops and moves another way just like it did touch the probe plate. But it didn’t. It happens when working from touchscreen and from pronterface/repetier.
Well, that would work but I’m operating with LCD screen without PC connected so cannot send commands on the fly. Except maybe saving homing gcode commands in files on SD.
Do you know how to compensate for probe’s thickness? Assuming that probe is 5 mm thick, machine gotta understand somehow that actual zero is 5mm lower than it felt.
This g92 command should be called each time after homing and is meant to tell machine that it would need to move additional 5mm downwards before starting a session, right?
Edit. Oh I get it. It’s telling machine that it’s currently 5mm above the level and should be called after each homing. Thanks.
And the problem came back. Now even when I clear off and move away from the machine - it sporadically feels that it reached Z zero without actually touching anything. Taking wire out of RAMPS helps to prevent false triggering.
So far I don’t have any ideas of what is going on and how to solve it. I didn’t change anything since last successful operation.
I don’t have anything grounded, maybe problem is there?
The following comment in “recent” Markin sample configuration files could give you an answer:
/**
Endstop Noise Filter
Enable this option if endstops falsely trigger due to noise.
NOTE: Enabling this feature means adds an error of +/-0.2mm, so homing
will end up at a slightly different position on each G28. This will also
reduce accuracy of some bed probes.
For mechanical switches, the better approach to reduce noise is to install
a 100 nanofarads ceramic capacitor in parallel with the switch, making it
essentially noise-proof without sacrificing accuracy.
This option also increases MCU load when endstops or the probe are enabled.
So this is not recommended. USE AT YOUR OWN RISK.
(This feature is not required for common micro-switches mounted on PCBs
based on the Makerbot design, since they already include the 100nF capacitor.)
*/
//#define ENDSTOP_NOISE_FILTER
If you can, I’d suggest finding out if you can enable the noise filter for your configuration (and recompile), if not, trying and putting a capacitor as suggested.