Dear all,
Had a part scanned with a 3D scanner, got the .igs 3D dwg after scanning, then .dwg 2D converted from above 3D.But all the lines on this 2D dwg are spline,could not be taken directly.
Question is how to convert spline to solid line in AutoCAD?

If you mean convert spline to a polyline, a few ways to do that. If you want line segments, you could explode the polyline.1. Export to ver R12 dxf2. use Express Tools "flatten" command3. Use the lisp routine, "spl2pl.vlx"at http://www.dotsoft.com/freestuff.htm

Thanks for the reply.
But it seems not working in this way or maybe I did sth wrong.Can you show more details?

Which method did you try?And I wasn't real sure what you are trying to achieve. The methods I showed would convert  a spline to a polyline, which would still be a single object and contain arc segments. It would look about the same.

Thanks for the explanation.Quite clear how to convert spline to polyline,but what I actually need is to convert the spline to solid line or arc,which are the same as those drawn by [CMD]LINE[/CMD] or [CMD]ARC[/CMD]. 

Use "explode" to convert a polyline to segments (arcs and lines).

[QUOTE=CarlB]Use "explode" to convert a polyline to segments (arcs and lines).[/QUOTE]
With this method,segments are available,but they are all very short sections,just like cutted from a long line or curve.That's not enough for me,is there any way to connect these short segments to a long line or curve?

I thought your request was to make objects ARCS or LINES, thus the need to EXPLODE. Before you exploded the polyline, those objects were connected.  Exactly what AutoCAD object can you work with? Spline -no, polyline- no, arcs & lines- too many...