Switching to core XY : Firmware issues...

Hi everyone,
Thanks for reading my topic.
A while ago i had my prusa i3 that was wobbly and cheap all around. So i decided to upgrade it to a wooden core XY printer based on this design :
[www.thingiverse.com]

I have some issues with the firmware. I can't home certain axis based on the location of the endstops :
#define X_HOME_DIR 1
#define Y_HOME_DIR -1
#define Z_HOME_DIR 1

Here i can't home X and Z, they juste don't move.
Does it have anything to do with this ?

// Disable max endstops for compatibility with endstop checking routine
#if defined(COREXY) && !defined(DISABLE_MAX_ENDSTOPS)
#define DISABLE_MAX_ENDSTOPS
#endif

The only thing i did in the firmware was uncommenting the corexy feature

Here are some pics :



Thanks in advance for your help !

First, that's a nice looking build. I've been considering the same logical next step.

Second, looks like your end stops are on the opposite side of the machine that is shown in thingiverse.

Where were the end stops configured on your Prusa?

Mine are X - left (min), Y-back (min) Z-left/bottom (min)

// ENDSTOP SETTINGS:
// Sets direction of endstops when homing; 1=MAX, -1=MIN
// :[-1,1]
#define X_HOME_DIR -1
#define Y_HOME_DIR -1
#define Z_HOME_DIR -1

#define min_software_endstops true // If true, axis won't move to coordinates less than HOME_POS.
#define max_software_endstops true // If true, axis won't move to coordinates greater than the defined lengths below.

// @section machine

// Travel limits after homing (units are in mm)
#define X_MIN_POS 0
#define Y_MIN_POS 0
#define Z_MIN_POS 0
#define X_MAX_POS 200
#define Y_MAX_POS 200
#define Z_MAX_POS 200

I would always prefer to setup the end stops to "min" that way when they are activated, everything is at zero. This way the machine can count from zero to max_pos

if you only define "max" then how would it ever have a zero to start with?

Also built a CoreXY machine, and I'm experiencing the exact same problem.
Only the Y-axis will autohome. I haven't succeeded in solving it so far.

My machine is waiting for a new J-head. You could try some of the suggestions in this thread:
[forums.reprap.org]

But I think our problem is strictly CoreXY related.

Using Arduino Mega 2560 / Ramps 1.4 on latest Marlin.

Talk about a development version: [forums.reprap.org]

[github.com]

Fixed my problems. It was just hardware related. Connected and configured all endstops in the same way as the Y-axis, and it all worked like a charm.