What is going on with my Y axis?



I built my Wilson-II, super nice kit, and very happy.

Something is going on between auto-home and bed-leveling. My bed is ending up full +y HIT, prints are trying to start off the front edge of the bed glass…

I don’t know if the code is thinking the bed is someplace it’s not, due to misinformation/assumption about revision.

I have verified steppers all work. +x 1mm moves to the right. +y 1mm moves bed away from me toward the rear. +z moves up.

All switches report HIT when tripped.

All fans, extruder etc. work properly.

Any idea? Should I post video?


A positive move on Y should move it away from the end stop, i.e. towards you. you might have it wired backards (or configured backwards in the fw).


Hi, Squid.

The behavior is WORSE in that regard. It jumps teeth at full extension, and tries to press the extruder into the hotbed wiring.


Hi, team,

I found Marty’s fork of Marlin on Github, and see this in configuration.h:
// Invert the stepper direction. Change (or reverse the motor connector) if an axis goes the wrong way.
#define INVERT_X_DIR false
#define INVERT_Y_DIR true
#define INVERT_Z_DIR false

which matches the orientation of my stepper connectors on the PICA. And I wonder if this is the cause of the weird autolevel behavior - some assumption in the autolevel routine (which I have not yet looked at) assumes ‘false’.

Can someone point me to a link on build instructions for Marlin? I’m hoping someone can save me an hour or two search when I get home from work today. I have gcc/Eclipse, Atmel Studio, and the Arduino Software on various machines.


Edit: answering part of my own question: http://reprap.org/wiki/Marlin


Here’s a crappy iPhone vid of the issue.

First, I show y-motor direction, then second, autohome. Then things get weird on the autobedlevel. I shut it off because it’s pressing into the glass, and depressed the springs fully.

Then you can see my right sock. :flushed:


OK - I’ve failed to read the hex Marty shipped on the arduino Mega 2560 clone using the usb.

I did succeed in reading/backing up the original by using a USBasp programmer and the ISP pins on the board, so we’re in business.

Will report back later what tweaking firmware does… wish me luck :slight_smile:


well, things went south.

I tried to flip the #define INVERT_Y_DIR true

The LCD does not display.

I tried to reprogram Marty’s .hex file.

The LCD does not display.

I’ve tried with usbasp and arduino -cwired. Programmed for a Arduino/Genuino Mega 2560, usb port (solved that at least).



Sorry for the confusion in private chat… I didn’t realize the Github was only showing the latest version on Marlin.

There is nothing pre configured in the latest version. you have to set everything up from scatch. I suggest you go to the original version version till someone makes a writeup of all the changes needed to give you a 100% working Wilson.

You have 2 options. 1 trailblaze you way through the new latest and get it to work. or 2 re flash your PICA with the original mostly pre configured… make the few changes like what board you are using etc and do some printing.


Thank you! I’m back to the starting point with working firmware (except the bed-leveling).

I will try tweaking things.