Endstop distance after homing

Tomu

Hi guys I have a little problem here, After hit endstop min at X axis head is moving back arround 20mm. What can be wrong ?My Endstop distance after homing is set to 0

Repetier

Is this after the second end stop test? These

// When you have several endstops in one circuit you need to disable it after homing by moving a // small amount back. This is also the case with H-belt systems. #define ENDSTOP_X_BACK_ON_HOME 1 #define ENDSTOP_Y_BACK_ON_HOME 1 #define ENDSTOP_Z_BACK_ON_HOME 0set the planned distance from endstop after homing so you can have them untriggered on all moves.

Tomu

#define ENDSTOP_X_BACK_ON_HOME is set to 0 any way axis still is doing this funny move

Repetier

So how often does it test endstop in your case? Sounds like once go back and then it does not retest because endstop is already triggered. Test M119 after homing x and see if it is triggered also being 20mm aways.

Tomu

Homing procedure is normal this what I got here looks like ENDSTOP_X_BACK_ON_HOME is set, but is not. So X endstop is trigered X axis is moving back 5 again touching endstop one more time then, move 20 back.

MartinH

Tomu, pls post your config.h and i will look it over.

Tomu

Sorry I dod not have a time for that, will start again tomorrow then will sent you config

JR_berry

Hi all,

same problem here with my d-bot.
any solutions yet ?

Repetier

It is ok if you have a dual extruder. That way you can select second extruder at X0 without hitting the endstop. Homing with T1 active would then have no extra space.

JR_berry

i have indeed a dual extruder, a chimera from E3D.
and i used the settings from E3D, ext0 at -18,0 and ext1 at 0,0

than when i home x the carriage hit the end stop and moves away from the endstop to its starting position

but the carriage needs to stay against the endstop for homing Z-axis

i played with the extruder offsets and the park position after homing in the fw but it keeps moving away from the endstop.

Repetier

Yes it will in deed always move 18mm away if extruder 0 is selected. With E1 selected it will as you need it. Or if you have the x endstop at x max you would have no gap for E0 selected.

You can test if you can go to X=-18 then you could defined x home position to -18 with the risk of a crash if you home with second enabled. Requires homing order with preheat option which you can set to 0, but it will also show the option to set z homing position. Only thing is I'm sure normally the allowed coordinate test will prevent going to negative positions.

JR_berry

thanks, i have tested it with ext2, and yes it stays where i want it :)

is it possible to change the original homing script, so it always select ext2 while homing ?

Repetier

You could rewrite the G28 command in commands.cpp to store old extrude rid, select 1 do stuff and select back old extruder.