Home Z axis just go higher and higher. X and Y OK

[sebi9]

Hello,

with G28 X0 Y0 , it works well to home X and Y axis,

But for Z axis : G28 X0 Y0 Z0 it just goes higher and higher

So, when I print, It prints 2 cms above the level.

With G29, it goes higher too.

Could you help me?

ps :
Z axis is in the right sense on the printrboard (checked twice with pictures on the website), and probe sensor is working well.

Thank you!

[frankv]

You have a broken wire between the Z sensor and the Printboard.

[sebi9]

even if the light works well on the sensor?

Other question : if I put more slowly the printing speed, do I need to put the extrusion speed lower?

[frankv]

even if the light works well on the sensor?

Yes.

Other question : if I put more slowly the printing speed, do I need to put the extrusion speed lower?

Sorry, I don't know.

[RetireeJay]

Other question : if I put more slowly the printing speed, do I need to put the extrusion speed lower?

No. The actual extrusion speed is always calculated by the firmware, based on the printing speed, the filament diameter, the layer height, and the trace width (and the Extrusion Multiplier). When you specify an Extrusion Speed in the EEPROM, that's really just a Maximum Allowed speed.

The firmware always figures out which speed is the limiting one (if a Maximum Allowed is reached) and then calculates the other speeds to conform.

If you suspect under-extrusion or over-extrusion, you should check your Extruder Calibration (steps per mm) and the Filament Diameter that you are using in your slicer (it's best to measure the average filament diameter with digital calipers). Then, if necessary, adjust the Extrusion Multiplier.

[Mooselake]

For a test you can manually set the Z position with the power off (like rest the extruder on a piece of copier paper somewhere around the center of the bed), comment out the G29 and any reference to homing Z (like Z0 on a G28), and try to print.

The firmware will assume that the Z position at power on is Z0 (that's how you print without any home switches). You can't compensate for a tilted bed, but it'll help you figure out what's broke, and might get you going until you can sort out the probe issue and/or get a replacement. It could be worth a try.

Kirk

[2Mylent]

To know if this comes from the Z-Probe technician Printrbot made me do:
1) M119 for the state of EndStop (note the results)
2) disconnect switch Y
3) cabler Z-Probe on the Y connector
4) M119 again (compare with previous results)

[sebi9]

It's OK, I use it before Y stop. I remove G28 and G29 on cura, I begin at the right level, and I do a skirt while I adjust manually the Z height to be at the exact height. It works well.

[Mooselake]

Open a ticket with the place you bought it from, and get a new probe under warranty.

Kirk