http://www.zwsoft.com/forum/viewthread.php?tid=2273 Guys, can you construct any curve with spline? how do you draw a circle with a 3 degree spline? can you do it? [/indent] Profcad 2012-07-11 18:03:10 http://www.zwsoft.com/forum/viewthread.php?tid=2273&pid=15450 As Mentioned above, you can do a trick with Offset inZWCAD. This[url=http://www.zwsoft.com/Service_Support/ser_zwcad/Tips_and_Tricks/Snap_the_Rectangle_Center.html][b]spline[/b][/url] is a result of two offsets from an ellipse. 1) Draw the ellipse 2) Offset 5mm out 3) Delete ellipse 4) Offset 5mm in 5) Delete outer copy ravier 2012-07-17 10:04:42