why doesn't my printer obey the max table size? (confusing question)

all my stepper motors work but they don't obey the size of my table (The max position) and they continuously just go to the end of the rail without stopping when i want to print something even though i have adjusted the max size.
Here is marlin code ive been using


#define min_software_endstops true // If true, axis won't move to coordinates less than HOME_POS.
#define max_software_endstops true // If true, axis won't move to coordinates greater than the defined lengths below.

// Travel limits after homing
#define X_MAX_POS 200
#define X_MIN_POS 0
#define Y_MAX_POS 200
#define Y_MIN_POS 0
#define Z_MAX_POS 200
#define Z_MIN_POS 0

#define X_MAX_LENGTH (X_MAX_POS - X_MIN_POS)
#define Y_MAX_LENGTH (Y_MAX_POS - Y_MIN_POS)
#define Z_MAX_LENGTH (Z_MAX_POS - Z_MIN_POS)

why don't they stop, why do then just keep going?

What software are you using (Repetier Host, Pronterface, etc.)?

The software usually has printer settings where you configure the build area size. The slicer program might also have these params. I know Slic3r and Cura do.

The software i am using is Pronterface.
I made my Gcode using Slic3r and i made sure to configure the max bed size on both the slic3r and Pronterface but i still get the same problem.
I am also using ramps 1.4 and mega Arduino 2560 with Marlin firmware on them.

Edited 1 time(s). Last edit at 07/28/2014 11:10AM by bardiaesm.

Did you also configure the bed center? If it thinks the center of the bed is a corner or something it would try to go off. Also are your end stops in place and working?

you need to set the software you are using for its limits as well. and set if it is a max or min switch it is set for.


the software tells the firmware during a home to reset its distance. it is likely that somewhere the machine is told that the center of the bed is zero. this is often not true.


also in your slicer profile, like cura or repetier host, look for bed settings and set middle of bed to half of your machine distance.

if you indeed want the center of the bed to be zero, then you need to change your min and max on x and y to reflext so,

so for example change
#define X_MAX_POS 100
#define X_MIN_POS -100

only if you want the center of bed to be zero.