Part center Y position not matching drawing

[jim1108]

I have drawn the following part up on 2 totally separate CAD programs on 2 different computers and everything is identical. When I import the DXF file into Sheetcam, the lower right toolbar part center box always shows the y center as being -.0137 where as the part was drawn with a center of xo,yo. The position numbers in the generated g code look good. I have compared it to the actual drawing numbers. I cannot replicate the problem on any other drawings.
I used the fillet command for all the corner radiuses. The cad programs used were Draftsight professional and BiiCado Pro touch for and Android tablet.

[Les Newell]

When the part centre is calculated SheetCam first finds the extents of your drawing then uses the middle of those extents. It does not use the drawing origin. If you look at your drawing the distance from the circle centre to the highest point is less than from the centre of the circle to the lowest point, hence the offset. The drawing is placed where you drew it even though this is not the calculated centre point.

[jim1108]

I figured that is what it was doing. I drew up several other circles with the top .125 drawn straight and saw the difference in the Y position. Thanks for the response.

[jim1108]

I noticed that in the above posted program and others I have written the next tool called up will return to the previous tools last position of cut, then rapid to where it will actually cut. If you post the code look at the last xy coordinate a tool makes a cut or drill. The next tool will rapid to a predetermined xy by me, then the previous tool's last coordinate, do nothing, then to where it should start cutting/drilling. Any ideas why it does this? Otherwise, the program is correct with no errors, crashes, etc.

[Les Newell]

SheetCam has no idea where the tool is after a tool change so the next move it makes will specify X,Y and Z coordinates so the tool ends up in a known position. Try turning on 'No move to safe Z after tool change' in Options->job options->tool change. In that case the next move should be to the start of the next cut.

[jim1108]

Thanks for the timely response. Checking the no move to z box solved the problem. I did not think that box affected x,y coordinates, but now I do. So basically sheet cam was just referencing its last known position.