As Gerry mentioned, try DXF V12. Does the drawing look right when you load it into SheetCam? If it looks OK then the problem is probably due to a layer mixup. In SheetCam go to View->Layer tool. Now click on the tick marks next to the layer names. This will turn off all of the layers. Now turn on each layer in turn. This will show you exactly what lines are on each layer. You will probably find that some of the drawing is on a different layer to the one you expected it to be on. You can correct this in Rhino or SheetCam.
To move entities between layers, switch to contour properties mode (the button with an arrow and a C). Now hold down the <ctrl> key and click on the entities you want to edit. Once you have selected them, right click and select move to layer.
The warning you got about open objects is perfectly OK for a spiral. Lines that don't form a closed shape cannot be offset because there is no way for SheetCam to figure out which side of the line to cut. It is a common mistake to have lines that nearly meet but don't quite. If you have an outline that looks closed but in fact is open because some lines don't meet the warning will let you know SheetCam thinks it is open.
Les  |