Hi there,

I'm experiencing a strange problem with DXF export I never had before.

I've made a 2d drawing in MoI that when exported into DXF seems to be split up into polylines instead of cubic splines.

Export settings are:

Export type: 2D projection
Projection view: Top
Write curves as: Cubic splines

As said, this is the first time I experience this problem. I export regularly into DXF.

Due to confidential reasons I can't upload the entire drawing but a small part is ok to show. But it's not only polylines, the long and straight lines of the rectangles are divided into different segments from arbitrary length as well (red marks to show the problem).



Exported into DXF eDrawings 2016 (and other DXF viewers as well) renders the drawing as polylines.



It's kinda strange. If I use Rhino to export into DXF this problem doesn't occur.

Hi 3image, it looks like it's just how those viewer programs draw general spline curves, it's not unusual for AutoCAD to draw all curves as a series of line segments, there may be an option in the viewer somewhere for the density of lines to use.

Can you also send the DXF file that Rhino exported so I can take a look at why that's working better for your case here? My best guess is that Rhino exports these curves as a polyline entity that has arcs in it, either that or it creates individual line and arc objects, and your viewer program draws arcs in a better way than it draws general spline curve entities.

If you use Edit > Separate inside of MoI to break that long joined curve apart into individual lines and arcs, that will probably work better for you since then MoI will also create LINE and ARC entities for those rather than making a single longer general SPLINE entity.

- Michael

Hi Michael,

Thanks so far. Your tip with breaking all the elements up helped and now the exported DXF is rendered correctly. But I have to make sure if the CAM can use such a DXF file containing only separate elements.

Nevertheless, I've uploaded you the Rhino export, too.

On this topic also - is there a tool in MOI to convert splines into ARC for the purpose of laser cutting as some LASER guys still cant handle splines I currently send to RHINO and convert in RHINO have searched forum but cant find any scripts for same task.

Thanks
Alex.

Hi 3image, thanks for posting the Rhino DXF file. The Rhino file has general SPLINE entities in it, but they are all separated out as one separate entity for each individual arc and line, and they are not being rebuilt as cubics. So yes, using the Edit > Separate step in MoI should give you a similar output from MOI.

- Michael

Hi Alex,

re:
> On this topic also - is there a tool in MOI to convert splines into ARC for the purpose
> of laser cutting as some LASER guys still cant handle splines I currently send to RHINO
> and convert in RHINO have searched forum but cant find any scripts for same task.

Sorry, no MoI doesn't have any tool in it to fit a series of arcs along a general spline curve. I'd recommend using Rhino for that particular type of conversion as you are currently doing.

The other thing that would probably work directly from MoI would be to use the option for "Write curves as: Polylines" from the DXF export options.

- Michael