DXF R12 Export problems

[FLS]

Hi, 

I have a problem exporting to DXF R12 fortmat from VW 2019.

As you can see in the files attached when exporting my drawing to DXF R12, the polyline contour of the drawing "breaks" and i have tried everything i can think of and i can't export it correctly.

I don't have this problem while exporting to any other format. Even in R13 (see files attached) it works fine. 

I need to export it to R12, as the workshop i'm sending the file, needs specifically DXF R12 for machining ....

Can anyone help me and explain me how to avoid this issue? 

Many Thanks in advance!

F 

 

Archive.zip

[Art V]

10 hours ago, FLS said:

I need to export it to R12, as the workshop i'm sending the file, needs specifically DXF R12 for machining ....

If you are on Windows you could download DWG Trueview from the Autodesk website, then export to any DWG version that gives a proper output (e.g. even DWG 2018 should be ok) and then use DWG Trueview to convert the file into DXF R12 format.

 

The ODA (Open Design Alliance) has a DWG converter too that should be able to do this conversion. That converter is available on Mac and Linux as well as on Windows.

An alternative could be to use e.g. the free version of Draftsight to convert from e.g. R2018  to DXF R12 and it is also multiplatform.

 

I'll take a look at the files and convert to DXF R12 in the meantime.

[Art V]

A few things I noticef after looking at the VW file and doing some test DXF/DWG exports:

- The DXF R13 is not correct either, the entire outer outline is missing

- Exporting to a more recent version gives the same result as for the DXF R13

- "Unclosing" the outermost polyine in VW results in only the right half of the outermost polyline to be exported, as it is now in the DXF R12, it does close that part and that is why you see that diagonal line. The left half of that outline is missing. My guess is that the number of vertices is too large or there is something in the missing segment that causes it to not get exported.

 

The outermost polyline consists of 4500+ vertices. Simplyfing the polyline with a tolerance of 0 reduces the number of vertices with approx. 800 but does not solve the issue as it still generates the same result as in the DXF R12.

 

I think that the only way to solve this is to do two things if you want to export this from VW to DXF:

1. Simplify the polyline as much as possible, and do the same for all other objects because may of them use more vertices than strictly necessary. This should make it easier for the machining as well. Then try exporting again.

2. If the above still does not give you the outermost polyline in the DXF then break the polyline into segments of 500 vertices max., then export to DXF, then use e.g. Draftsight or another DWG based CAD program to connect the segments again into a closed polyline if required for the machining. If there are still issues with missing  parts of the outermost polyline you may need to break it into segments with even less vertices (e.g. 300 max. or whatever it takes to get all segments exported)

 

In other words: clean up the drawing as much as you can by reducing the number of vertices in polylines and breaking up polylines with very large number of vertices into smaller segments without affecting the shapes/contours and then combine the segments in a DWG program if necessary.

Edited March 17, 2019 by Art V

[FLS]

Dear Art V.

Thank you so much for your help.

You are totally right, it seems that the problem is the number of vertices that has to be reduced.

I'll follow your indications and thanks for the software tools i didn't know about!

You have been really helpful ! Thanks !

F

[Art V]

@FLS During a break I did a test by converting the outermost polyline to lines in VW, export that as DXF and recombine it into a polyline  in BricsCAD and then inserted the DXF R13 file into it.

 

The decomposing ot the outermost polyline resulted in 51,000+ lines but it could be recombined into a polyline in Bricscad with the same number of vertices. Despite the the resulting DXF R12 file it generates is almost half the size of your DXF R12 so it seems to me that something isn't going right with the VW to DXF R12 export.

 

Attached are both an ASCII and a binary DXF R12 export of the above. Though the machining workshop might not like that outermost outline with 51,000+ vertices.

 

It might be an option to decompose the polyline to lines in VW and then compose it into a new polyline and try to reduce the vertices from there if possible. Just in case it is an issue with the polyline itself.

 

@Jim Wilson is there an upper limit in VW for the number of vertices when exporting to DXF R12 or any DXF/DWG version? (Or importing for that matter as that is more common for me to run into but I don't recall objects imported in the past that hat 4500+ vertices in a single polyline).

DXF R12 ASCII.zip

DXF R12 Binary.zip

[PVA - Admin]

On 3/18/2019 at 8:23 AM, Art V said:

@Jim Wilson is there an upper limit in VW for the number of vertices when exporting to DXF R12 or any DXF/DWG version? (Or importing for that matter as that is more common for me to run into but I don't recall objects imported in the past that hat 4500+ vertices in a single polyline).

 

@Nina Ivanova do you happen to know the answer to this?