Welcome to the SeeMeCNC Community

When I use G1 Z0 F1200 or G1 Z50 F1200 my printer gets about a foot from the bed and stops.

I'm manually lowering the printer using the controls in Repetier Host then doing a G28 and executing one of the two commands above. No matter how many times I do this, nothing changes. I also increased the Z_HOME_POS a few times, compiled and uploaded but that changed nothing. What am I doing wrong?

EDIT: I've increasd my Z_HOME_POS to 600, still not getting within an inch of the bed but getting closer now.

EDIT2: G1 Z0 F1500 almost touches the bed. I'm stopping here. But I had to increase the Z_HOME_POS to 726. Is this right?

If you do say
G1 Z50 F1200
Then
G1 Z60 F1200

How far does it move, if it's 5mm instead of 10 then you have a newer RAMBO board, apparently the new RAMBO boards support 16x micro stepping and the firmware values are calibrated for 8.
You need to edit configuration.h and double the steps/mm for the axis.

Thanks, I'm using these values and it seems to be where it should be at Z50 now.

#define DEFAULT_AXIS_STEPS_PER_UNIT {106.666, 106.666, 106.666, 292.0}

I'm getting the same issue with it stopping half way. How do I change it so it matches?

You have to edit configuration.h and double the steps per unit for the 3 axes AND don't forget the extruder! It is configured lower down in the file in the extruder configuration section.

Thanks, I did forget the extruder. I don't see an extruder section, what is the variable's name?

Right below STEPS_PER_UNIT I do see "DEFAULT_MAX_FEEDRATE {200, 200, 200, 60}" set to but my old STEPS_PER_UNIT was 53.3 and there aren't any other variables with that value.

So I changed the the following but I too don't see the extruder conf. section.

#define DEFAULT_AXIS_STEPS_PER_UNIT {106.666, 106.666, 106.666, 292.0} // default steps per unit for rostockmax

Also with this setting when I change the Z_Home_Pos by 10, I get a movement of about 7.0mm.
Isn't it suppose to move 10mm?

#define EXT0_STEPS_PER_MM 584

In Repetier firmware. It was originally set to 292.

supra89vang wrote:So I changed the the following but I too don't see the extruder conf. section.

#define DEFAULT_AXIS_STEPS_PER_UNIT {106.666, 106.666, 106.666, 292.0} // default steps per unit for rostockmax

Also with this setting when I change the Z_Home_Pos by 10, I get a movement of about 7.0mm.
Isn't it suppose to move 10mm?

The 292.0 is the extruder steps per mm.