Hallo,
i hope, someone can help…
If i print on my Vertex 3D (V1.1 Firmware), all prints are shifted 20 mm on y-Axis. It is unable, to get a print, bigger then 16cm y-Size. I´ve tried thousand of settings in Repetier Host, but this Problem is for me unable to solve.
For testing i´ve tried to print a 18cm Circle-Object, see the Image 
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What can i do? The Printer takes all manual movements fine. I get manually all Positions from 20 - 200mm on y-Axis and 0 - 200mm on x-Axis. I have no idea, why this shifting Problem occurs.
(sorry for bad english, is not my native)
Very sad. today i tried to find another Solution and recompiled Firmware 1.1 with Arduino 1.0.6 (before was 1.6.0). But nothing changed, i got the same results. The Printer Homing works fine… manually i can select all Positions on y-axis but when it prints, the object is shifted 20 mm and i´m unable to print things bigger then 16 cm on y-axis.
Can someone try to print an 18cm cirle object for testing and post the results? It is a generally problem or must i search on my side only?
Next Try…
I´ve generated G-code with another Software (Slic3r) and printed it from SD. I got the same Results. So i think my Problem is Firmware related (Hardware works fine, no Layer Shifting, perfect Homing et c.).
Any help would be fine …
Last Try and Problem fixed 
It is a Bug in the firmware. It sems, that the defined y-Range (Max: 200 and Min 20) will be wrong processed. As workaround i have changed the Range in the configuration.h:
// Travel limits after homing
#define X_MAX_POS 200
#define X_MIN_POS 0
#define Y_MAX_POS 180
#define Y_MIN_POS 0
#define Z_MAX_POS 190
#define Z_MIN_POS 0
//Manual homing switch locations:
// For deltabots this means top and center of the Cartesian print volume.
#define MANUAL_X_HOME_POS 200
#define MANUAL_Y_HOME_POS 180
#define MANUAL_Z_HOME_POS 0
Now my Printer has the Homing at X:200 and Y:180. And the Range goes from X: 200 - 0 and Y:180 - 0
After changing the coresponding values in Repetier Host i got my 18 cm cirle. And the Placement works fine. No Shifting and no Cutting at the end of the y-Range.
Finally a hint for everyone: be shure that the thermal sensor from the extruder has a good contact to the heating Body. Fill the mounting hole with something or stick it in with special thermic glue. this is essential for the thermal regulation and prevents overheating. This can solve many of the printing problems described in this forum.
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