DXF export of POLYLINE entities

tom_hrabchak

Hi, 

I want to share a problem/inconvenience that I ran into yesterday and am interested in any suggestions for how I can avoid the problem next time.

I made a simple model of a ping pong paddle that I was planning to cut out of plywood using a laser cutter. The laser cutter is a lasersaur and has an application that can import an svg or dxf. When learning to use the laser cutter it was recommended that I use an svg created by inkscape as that had been known to work the best. So I exported the main curve of the paddle as a dxf and was planning to import it into inkscape, save to svg, and send to the laser cutter. However when importing to inkscape I got an error message saying that the POLYLINE entities could not be imported. The imported graphic was unusable because most of it was missing. Inkscape is open source so I read through inkscape's dxf import code and it looks like it doesn't support POLYLINE entities but it does support LWPOLYLINE entities. Similarly, the lasersaur app doesn't support dxf POLYLINEs but does support LWPOLYLINEs. 

I was able to workaround the problem by exporting to dxf from onshape, importing the dxf into NX, exporting a new dxf (which used SPLINE instead of POLYLINE), importing to inkscape, and exporting as SVG. But this workflow seems unnecessarily long.

I would image that importing dxf POLYLINEs isn't a problem for more sophisticated CNC machines but I only have access to the lasersaur. I don't think onshape is exporting incorrectly although it would be better for me if dxf export (release 13) exported my curve as a LWPOLYLINE. From what I gather, LWPOLYLINE is a more efficient entity in release 13+ for conveying 2D polylines than POLYLINE is, and apparently it is better supported by other applications.

I'll try to look into contributing a POLYLINE parsing enhancement to inkscape and lasersaur because it'd be cool to contribute to their open source projects. I just wanted to convey my experience with this to the onshape community because others might run into it also.

Any thoughts or ideas?

Thanks for reading!

viru

@tom_hrabchak, Please refer below thread which will be helpful to you,
https://forum.onshape.com/discussion/1421/dxf-dwg-import-from-illustrator-not-working

tom_hrabchak

@viru, thanks for the link. It's relevant, but I am going in the opposite direction- exporting dxf from onshape, rather than importing it into onshape. I agree with the last few posts however. If onshape was able to import an svg into a sketch, it would be a major improvement.

viru

@tom_hrabchak, Please raise a improvement request for this. I hope that in future Onshape will definitely provide this type of capability.