Problem exporting to previous version

[isaac]

We are surveyors working in Civil 3D 2013.  We sometimes need to export drawings back to previous versions for architects.  This can produce unpredictable results.  It was suggested to me on another forum to use the command PROXYGRAPHICS, change it to 1, and then export to a previous version.  This worked on some drawings.

Yesterday, however, I tried this method and the architect sent me back a PDF saying this is what it looked like in model space when he opened it.  Any ideas what causes this and how to fix it?  

[Jay_B]

Do the drawing units match? Architectural dwgs are often inches and civil in feet.
While it's not always possible to have all units match in a collaborative environment
It's worth checking into whether this is part of your annotation scaling issue.
Verify the units in each dwg by entering -DWGUNITS @ command line and compare the MS scale vs VP scale and they should match if both dwg units match.
Have you exported the file to AutoCad dwg or are they referencing your C3d dwg?

[Neilw_05]

It may be related to annotation scale. When exporting to older versions of DWG that do not suport annotation scale, Autocad creates multiple copies of annotative objects, one for each scale used in the original drawing. It can be a big  mess. I believe you'll see this when saving to ACAD 2006 or earlier.

[JBR-1]

Have you used the export form the file pull down menu

I us it a lots of times no problems

[jtelder · Accepted solution]

I use Dwg True View. It seems to work better than the stock program's conversion and export stuff. You can download it free from here-

http://usa.autodesk.com/adsk/servlet/pc/item?siteID=123112&id=9078813

Once installed just go to the "D" in the top left corner and pick DWG convert. In the dialogue box, you can use their choices, of fix up your own with the conversion setup button. One of the choices is to "Maintain visual fidelity for annotative objects". Keeps things looking the same. You can also bind x-refs and purge the dwg to save space, and clean things up. Once you have it fixed up, it will save your settings, then just drag and drop your dwg into the box and hit convert. Quick fast, easy and clean...

[DaveM]

"It may be related to annotation scale. When exporting to older versions of DWG that do not suport annotation scale, Autocad creates multiple copies of annotative objects, one for each scale used in the original drawing. It can be a big  mess. I believe you'll see this when saving to ACAD 2006 or earlier."

Is this where the savefidelity command comes into play?

[Neilw_05]

I've experimented with the SAVE FIDELITY variable but it doesn't seem to help.

[isaac]

I think it is an annotative scale problem as Neil suggests.  I will try True View.  Thanks for the suggestion.  

[Neilw_05]

Please post the outcome if you get it to work.

[isaac]

After converting in TrueView, I still ended up with two layers of text, one at 20 scale and one at 4 (both of which I had used in the Civil 3d drawing).  But I was able to just freeze the 4 scale text layer and everything else looked fine.  Contour labels, spot grades and bearings/distance were all at the correct scale.  Thanks, JT.

Betsy

[Neilw_05]

Could you check something for me? Is the exported file considerably larger than the original? Also do you find blocks and layers in the exported file that begin with the name "AECobjExplode.."? Are there any AEC proxy objects in the exported file?

[isaac]

Yes to both questions--the original file was 1286 KB; the exported one was 3463 KB.  There were several layers in the exported file beginning with AecObjExplode. It looks like the different layouts we have in our template, each followed by another layer "AecObjExplode_Vport_"

For example:

AecObjExplode_36x24 Horiz_Pspace

AecObjExplode_Vport_702

AecObjExplode_24x18_Pspace

AecObjExplode_24x18_Vport_7F3

[Neilw_05]

This is what we get when use the Export to Autocad tool. Apparently DWGTRUECONVERT does the same thing.

Be aware that those blocks can bloat the exported file to very large sizes depending on the source data which degrades drawing performance considerably. They also add numerous unwanted layers to your list.

Getting rid of those blocks and layers is another major part of the process if you need a clean and efficient file.

[Jay_B]

When Using the "Export to AutoCad" from within Civil 3d as has been suggested a couple times in this thread, the resulting file is usually considerably smaller in size and the layer names  are as they were in the original file with no additional Layer prefixes etc.

[Neilw_05]

That is not true in my experience Jay. Can you run some tests on your end and see if you get those blocks? Try exporting to 2004 using a source file that has C3D objects and anno displayed at different plot scales in the layouts.

[Neilw_05]

Another problem I've just discovered: C3D objects in Paper Space do not get processed when Exporting to Autocad. They come across as proxy entities.

I have a file with C3D labels in Paper Space. After converting I have to explode all those labels. The result is exploded leaders (leaders and arrows are pieces of lines). It's a mess.

[Jay_B]

Neil,

No renamed "blocks" or "layers" but yes the various AECC_* civil 3d objects ie: figures, cogo points etc. exist in the exported file.

My files were exported to 2010 Acad from C3d 2012.

[Neilw_05]

You won't see the problems Betsy is having until you export to an older version that doesn't support annotation scale.

See what happens if you go back to 2004.

[jtelder]

Glad I could help, Betsy. (BTW, My condolences on having to deal with architects)

I had forgotten about the problems with blocks and paperspace stuff. I am in the habit of exporting the points to a text file, then opening the basic acad template and copying all my lines, arcs, plines, text, etc into it. Then convert everything to plines and reg text. That way no paperspace stuff, no blocks, no problems. The file size does increase a little. (the last one I did was 1057kb's and increased to 1138kb's, so no biggie). Then send the file along with the points text files attached. If they need paper space stuff, I just send pdf's.

[Neilw_05]

Betsy,

Would you mind running one more test for me? In my experiments I've discovered those pesky blocks and layers are not created if you export the file while in model space.

So could you please try this to verify:

Open your C3D file and go to model space (not through a paper space viewport), then export to Autocad 2004. Then open the export file and see if the AECobjexplode layers and blocks are created.

Next repeat the process but this time do the export while in a layout tab. Check for the blocks and layers again.

Also note any difference in file size between the 2 exported files. Is there a difference in the results between the 2 export workflows? Does the file from the model space export appear to be complete (no missing data in the layouts)?