Disable endstops

mahesh04

Hi repetier,
What can i do if i want to disable endstops while printing using M121 command.

Repetier

That is not implemented. In fact you can only change that behaviour at compile time setting ALWAXS_CHECK_ENDSTOPS.

mahesh04

making ALWAYS_CHECK_ENDSTOPS 0 causes issue when autobed level sensor does not detect the bed for some reason it gives an error that "Probing had returned errors - autoleveling canceled." , after this motor moves to the Zmax & never stops though the end stops triggered. I want to disable endstops while printing, and keep them enabled ( especially Zmax) while autobed level process is on how can I do that?

mahesh04

we are an OEM using your firmware + repetier server softwares as a bundle with our machines, and we are facing this issue as large format machines tend to false-trigger proximity sensors in operations especially when they are running for more than 100 hours..
this causes shift in the print when end stop check is left on..

please help me with this asap

Repetier

As I said, recompile firmware with
#define ALWAYS_CHECK_ENDSTOPS 0
in configuration.h and it will only use endstops for homing, so shifts from cross talk signals will not happen.

In the V2 version you will be able to change this behaviour in eeprom settings, but for V1 this is the only solution.

swapsan

when can we expect V2 version ?

swapsan

Repetier said:

As I said, recompile firmware with
#define ALWAYS_CHECK_ENDSTOPS 0
in configuration.h and it will only use endstops for homing, so shifts from cross talk signals will not happen.

In the V2 version you will be able to change this behaviour in eeprom settings, but for V1 this is the only solution.

I have faced this issue too can we disable endstop check through some command on initialisation and then at the end of Gcode enable it again?
This is a major issue and needs to be addressed for large format 3d printing.

swapsan

Repetier wrote
As I said, recompile firmware with
#define ALWAYS_CHECK_ENDSTOPS 0
in configuration.h and it will only use endstops for homing, so shifts from cross talk signals will not happen.

In the V2 version you will be able to change this behaviour in eeprom settings, but for V1 this is the only solution.

There are 2 issues with this solution -
1. while machine performs auto bed level if auto bed level sensor does not detect surface for some reason and hits Zmin then gantry goes to zMax, now this gantry tries to measure Z axis height and stops after it hits Zmax switch, when you make Always_check_endstop 0, this gantry motion is not stopped by Zmax switch and causes damage to print.

2. Also if I keep Always_check_endstop 0 and if user starts the machine and does not perform homing and directly tries to move any axis the motion will happen and without checking endstop, this is a serious issue as this can cause accident and break the machine. I use repeaters server + repetier firmware

Roko

FWIW one solution seems to be to find and eliminate the spurious noises (cross talk). I don't think you can program a "prediction" of when crosstalk could happen. Or add some kind of limit detection that will stop the movement if a physical limit is reached that is not related to endstops circuitry. Maybe a device that will disable power or set an error condition to stop the machine.

RAyWB

mahesh04 said:

we are an OEM using your firmware + repetier server softwares as a bundle with our machines, and we are facing this issue as large format machines tend to false-trigger proximity sensors in operations especially when they are running for more than 100 hours..

from my experience best solution is to use a mechanical endstop combined with additional optocoupler located at controller side.

the simple trick is that you have the switch controlling the led current which is around 20mA so spikes coming from crosstalk or other external sources will not trigger the endstop.

also some poor quality mechanical endstops will live for some 100000 switch cycles and last but not least they won´t change over temperature.

i do this on my home made mill having a 2.2kW spindle mounted including frequency converter generating a lot of emc based noise but never triggered this kind of endstop.(test period 3 years)

Repetier

Firmware has options to prevent movements before homing, so that is not the biggest problem.

V2 is already there, but many boards and drivers are not supported. So it depends on your hardware if you can already use it or not. But it will of course have same electronic problems with false signals. That is something oyu need to solve hardware side best like twisting sensor cables, make sure they are not too close to power cables (motor, heater).