I swapped the extruder out today for a e3d and that in turn dropped my nozzle down around 6 mm. I set this in panel menu as zmin 6mm. Wrote to eeprom. Go to zhome from panel menu, all looks good. Issue a print and it bed crashes until I power it off. Turn the printer back on and zmin is now back to zero. It almost took me 5 hours to install the new extruder and get everything back together, so I could just be fried. Am I doing something wrong? Is there something else I need to do to set my zhome down further?
Ok, so 6mm was small enough to just drop the bed, so I still dont know how to set zhome to something lower. If someone could post a link oh how to do this I sure would appreciate it.
After working on it all day, Im able to get a tiny calibration print off before I pass out.
Zmin does not change home position, just says home position is Zmin, sensor is still in same place, to solve your issue change sensor position or as someone did on forum add piece on top of Zcariage to make it higher, so bed will be lower when find sensor
Hope it helps
Thanks Luc, I understand now. Zhome is zsensor home and to alter that you have to alter physical location of sensor. Probably safer that way now that I think about it.
Is there a problem with your z-sensor? Even if the extension was removed or placed incorrectly, the bed-frame would trip the sensor prior to hitting anything other than the extruder (if it was over your bed). I did change the z-travel value in g-code to prevent exceeding physical space when travelling down (like when a print is complete, if you have the bed lower to the bottom). I think I also changed the z-travel limit in the eeprom to 172 from 192.
zsensor is good, my best guess is the extended piece didnt line up exactly with my sensor and instead of tripping the sensor it got pushed behind it, and the additional part hit the sensor housing and exerted both upward and downward pressure on Z. The piece that clips onto the bed carriage will inhibit its ability to trip the sensor if the piece that is supposed to trip it, doesnt. I should have printed the piece with PLA so it would have just snapped when flexed. I am spending more time printing than troubleshooting now, so all said and done Im happy that I swapped nozzles, even if my z is a little wobbly now.