Pressing X home (pronterface) button and extruder goes away from the endstop

Hi.
I've just finished to build my first 3d printer, a Prusa i3 Rework.

I'm trying to modify the Configuration.h file but I'm having problems configuring home position.
My three endstops are positioned exactly like in the following picture: just because I still don't have understood how you have to place yourself when describing your 3d printer (just let me know) I usually describe my 3d printer considering myself placed in the same position of the Y endstop, looking at the RAMPS board and the "mirrored" PRUSA sign.


So.. I have 3 endstops and it seems that it is useful to consider them as MIN endstops and possibly use *_MAX_POS parameters. Am I right ?

While connected using pronterface, motors seems to work accurately, even if now I'm noticing Y motor has sometimes difficulties to bring forward (distant from the Y endstop) the hot bed, grating a little bit (this is a new problem because as you can read I was focused on the X motor): it seems that once pronterface is connected, the 3d printer believes to be positioned at 0,0,0 so every X-, Y- or Z- command is ignored. This is happening to me. Is it normal ?

When I press Y or Z home buttons from pronterface, Y and Z motors go to their respective endstops and they stop opportunely.
When I instead press X home button, the extruder goes to the right and not to the endstop positioned on the left. How can I modify the Configuration.h file so when X home button is pressed the extruder can point to the left where it would find the endstop ?
I'm attacching the Configuration.h file I'm using.

Thank you!
Marco

I've had this problem before. Does it only move a few steps? Use M119 to check your end stops, if it says x is triggered that means you may have a bed endstop connection.

I think the movement is right and the M119 command says all the 3 endstops are OPEN. They work very well. I've triggered them and checked with that command.
If I disconnect the motor (using pronterface I mean) and then I manually move the extruder to the left (few mm near the X_MIN endstop) I can move it without problem with pronterface commands: the problem begins when I press X home button. I'm expecting the extruder goes few mm back touching the X_MIN endstop, while instead it starts pointing to the right.

I only would like to constrain the extruder pointing to the left where is my endstop, even if now when I play X+ the extruder goes to the right and when I press X- it goes to the left.

If it goes away from the endstop while homing reverse the motor lead.

Your looking at it backwards... thats just weird. You need to look at it from the front, with the words the correct way

First check direction of movement of X, X+ movement should move the head right, X- movemnt should move the head left.
If this is incorrect you need to change #define INVERT_X_DIR true to #define INVERT_X_DIR false (or turn the stepper plug around 180 degrees, while power is off , but not both firmware and plug!)

The pictured the endstop is a X max, and you need to set #define X_HOME_DIR 1 (this looks correct for you)
You may need to tweak #define X_MAX_POS 190 this set the size of you X axis... not sure why its not the full 200.

Edited 2 time(s). Last edit at 09/25/2015 04:25AM by Dust.

Many thanks for your support.

Yesterday I was able to correctly setup my 3D printer.

I'm attaching again my file Configuration.h