Ed Would, Managed to get a mk2a bed 300x200mm amended the settings to
#define X_MIN_POS 0
#define Y_MIN_POS 0
#define Z_MIN_POS 0
#define X_MAX_POS 281.5
#define Y_MAX_POS 157
#define Z_MAX_POS 248
limited by the extruder movement
#define BED_CENTER_AT_140.75_78.5
in S3D
Build volume
X 281.5
Y 157.0
Z 246
Origin Offset
X 140.75
Y 78.5
Z 0.0
Still went to the rear right to start print, but after 2 days off changing settings in the F/W and S3D I finaley sorted it out and it was so simple
Put all F/W setting back to what they were apart from the above bed/print area and in S3d put the Origin Offsets to
X 0.0
Y 0.0
Z 0.0
and hay presto its printing in the middle and the print preview is also in the middle.
But once again thanks for All the help and suggestions from all off you
#define X_MIN_POS 0
#define Y_MIN_POS 0
#define Z_MIN_POS 0
#define X_MAX_POS 281.5
#define Y_MAX_POS 157
#define Z_MAX_POS 248
limited by the extruder movement
#define BED_CENTER_AT_140.75_78.5
in S3D
Build volume
X 281.5
Y 157.0
Z 246
Origin Offset
X 140.75
Y 78.5
Z 0.0
Still went to the rear right to start print, but after 2 days off changing settings in the F/W and S3D I finaley sorted it out and it was so simple
Put all F/W setting back to what they were apart from the above bed/print area and in S3d put the Origin Offsets to
X 0.0
Y 0.0
Z 0.0
and hay presto its printing in the middle and the print preview is also in the middle.
But once again thanks for All the help and suggestions from all off you