Z Axis home position [solved]

[russellz]

Just got my Acrylic Prusa I3 pro B working and tried my first test print.

I homed all axes and leveled the bed then loaded my stl file, sliced with Slic3r and hit print.

The printer tried to print the first layer about 2 mm above the bed - disaster. Searching the forum I found a number of posts regarding strange homing behaviour on the X axis. So I started to plough through the firmware source. In the file "Configuration_adv.h" I found this section:

Code: Select all

//homing hits the endstop, then retracts by this distance, before it tries to slowly bump again:
#define X_HOME_RETRACT_MM 5
#define Y_HOME_RETRACT_MM 5
#define Z_HOME_RETRACT_MM 2

The idea of this is that, if homing is done at high speed, the axis might overstep the switch actuation position with inertia so it retracts and tries a second time more slowly. The software assumes that the retraction is enough to de-activate the end-stop switch. If the switch is not de-activated by the retraction the software assumes that it has reached the activation point and stops any advance.

Changing the last line to

Code: Select all

#define Z_HOME_RETRACT_MM 5

and reloading the firmware fixes the problem.

It must be about time that Geeetech updated the firmware on the website and installed in supplied kits to fix all known problems - please.

Russell.

[William]

Thanks for your sharing.

[ZCC]

I have the same problem. I just upload the firmware with value 5 on Z retract and it still happens. I tryed reupload with "2" on Z retraction and the problem persist on the same way



My printer is a Aluminium I3 A Sanguino

[William]

Can you attach a video about your problem？

[ZCC]

http://www.youtube.com/watch?v=29qzheZEon8

I tryed other slicer and the same problem. I will test update a new firmware changing the printer name, just to test if the arduino is really updating correctly

[William]

Thanks for your video showing the issue，you need to update your firmware version，and here is the link：
http://www.geeetech.com/forum/download/file.php?id=2819

[ZCC]

Thanks for your video showing the issue，you need to update your firmware version，and here is the link：
http://www.geeetech.com/forum/download/file.php?id=2819

Thanks for support.

This firmware don't fit in my sanguinolu board (At least, i cound't upload it).

I tryed upload the version "Plusa_I3_A_sanguinololu(for the upgraded kit using lead screw).zip" and it worked. Problem solved.

[William]

you are welcome，your problem solved that was the best.