Not working correctly Z axis umo+

[Rudy102 1]

Hi all,

I have finally assembled my heavilly moded ultimaker, it's running um2 electronics and bed. My issue is that after loading stock firmware the Z axis after, lets say command for move 10cm, only do 1mm. After changing the steps, from stock 200 for Z axis, to 800 and having correct reaction to gcodes for moving, the axis is not able to do fast moves. When for example want to move it from 200mm to 5mm it only scream and stay in place.

Anny ideas how to fix this? :(

I have played with steps, current, microstepping, but it seems to not work :(

[neotko 1,417]

Z microstepping is set by a switch (not firmware) so probably you have it at default (no switch) 1/8 microstepping

Also without knowing more about the mods is hard to guess

[Rudy102 1]

Frame is UMO,

motherboard with lcd from UM2,

heated bed with lead screw from UM2,

igus rails and bearings on Z and XY axis,

aluminium XY carriage,

UM2 style print head with Olsson block dual extrusion.

I can't see anny jumper on motherboard, something is not right because with stock 200 steps the Z axis is doing around 1/4 of normal movement.

Edit. Found the jumper, it was open so in 1/8 step. Using prusa calculator for my acme srew with 2mm per rotation I get 800steps. It's correct for movement but when asking printer for a move from 200 to 0 it scream and not move.. Not sure is it related to hardware issue or too much acceleration for example.

Edited August 8, 2017 by Guest

[neotko 1,417]

Well it should move unless your stepper cables pairs are wrong or not making contact. You can try to printrun/pronterface by usb and just move up/down to see if it’s just moving in reverse (hense the screaming noise) or its a faulty motor?

[Rudy102 1]

The motor is fine, also moves are correct in pronterface. The issue is only appearing in fast raising of the bed, for example at first power up uf the printer when it lower bod to bottom, and then fast raise it up to nozzle. It's look like too much acceleration but Im' unable to find comand for Initial startup of printer in Marlin for Z raise

[neotko 1,417]

JESUS posted the answer 3 times and all erased..

Ok again.. I don't see how acceleration can affect that, you can use M204 gcode to change it to see any effect on it. I think you have the highend/lowend of the endstops inverted and the motor keep's going down to find an endstop that isn't there

[Rudy102 1]

Fixed, changing DEFAULT_MAX_FEEDRATE and DEFAULT_MAX_ACCELERATION for Z axis to smaller value helped.