Perfecting DWG Export

[Andy Thomson]

I am just having to get at this again. I had everything working pretty nicely in 9 (especially from Plotmaker), and now my settings/translators have to be rethought.

I would like to ask what problemmatic issues people are having with their DWG exported ArchiCad files in an effort to learn workarounds and tricks towards better export.

Some examples of many that I intend to cite here is this:

Units, when exported from AC10, in feet (1 foot = 1 drawing unit)
On opening in AutoCad, gives engineering units in decimal feet. AutoCad shows exported DWGs in decimal feet (when measuring/working). On changing units to 'Architectural' (fractional inches) - the whole of modelspace requires to be scaled by a factor of 12 - why? How can I export with architectural units so that rescaling is not required? (is it as simple as exporting 1 unit = 1"?)

Rescaling presents a host of other issues (WB3.5 parts eject redundant lines all over the place that need to be cleaned up)

Also, when ArchiCad flattens drawings, there are a bunch of redundant fills and lines - over and above those that can be thrown on to specific fill layers, and exploded complex elements seem always to create an elaborate mess of blocks - not exploded primitives.

What I am after is a light, simple, clean DWG, with 'purged duplicates' as it were, and more or less WYSIWIG export/import. Why can't I 'purge' BEFORE export! (wish?)

Images - why do some have frames, and others do not?

Pens - why do all pens, while preserving pen colours, never show anything but white pens in the layer list? Bylayer export doesn't change this. The convertpstyle tricks also haven't remedied this....has something to do with everything being blocks, not actual linework.

As I am not an AutoCad user, forgive me if I sound like I am talking out of my a**, I am. But I am just repeating common complaints about my 'inferior' ArchiCad DWG export, and I'd like to get to the bottom of all of these issues. Your thoughts, elucidations are valued. Thanks in advance!

[Thomas Holm]

andyro wrote:
I am just having to get at this again. I had everything working pretty nicely in 9 (especially from Plotmaker), and now my settings/translators have to be rethought.

Sorry for being late to this. But I guess we'll have to live with these issues for years to come. When is the first Revit translator coming? Or do we really believe that the dwg format will suffice? Or that Autodesk will bow to a true IFC implementation in Revit?

...Units, when exported from AC10, in feet (1 foot = 1 drawing unit)
On opening in AutoCad, gives engineering units in decimal feet. AutoCad shows exported DWGs in decimal feet (when measuring/working). On changing units to 'Architectural' (fractional inches) - the whole of modelspace requires to be scaled by a factor of 12 - why? How can I export with architectural units so that rescaling is not required? (is it as simple as exporting 1 unit = 1"?)

Well, yes. When you export you should always set the Drawing Unit in the translator to what you want it to be in the resulting DWG, to get a correct model space 1:1 drawing.
But in later Autocads, there is an INSUNITS setting as well. (I'm not sure, but I guess it's intended to handle situations where you XREF a dwg with a different DWGUNITS setting than the master file). In Archicad9, there was a translator bug that didn't set this correctly. It' supposed to be right in AC10. I haven't got any problem reports from my consultants, yet.

...What I am after is a light, simple, clean DWG, with 'purged duplicates' as it were, and more or less WYSIWIG export/import. Why can't I 'purge' BEFORE export! (wish?)

I hope GS is working on this. I also hope we get a 'total explode' setting back - I think there was one some years ago.

Images - why do some have frames, and others do not?

No idea.

Pens - why do all pens, while preserving pen colours, never show anything but white pens in the layer list? Bylayer export doesn't change this. The convertpstyle tricks also haven't remedied this....has something to do with everything being blocks, not actual linework.

I guess you mean the pen list in Autocad? If so I don't know. But I've run across a similar issue when I'm importing into Archicad. I've solved that by have two identical pen tables with different names. If I switch between them, the colors come back.
It may be that Archicad has problems producing a true BYLAYER export, since in Archicad, every entity has it's own attributes. In Autocad, the old default is that the attributes belong to the layers. Of course this multiplies the number of layers. I simply refuse to export BYLAYER, since it makes round-trip translation impossible, unless I completely change my work process. (I had the same problem in the Microstation days - that program is/was also a lot smarter than Autocad).

But I have stretched as far as using the old default Autocad pen table as standard. While a bit illogical, it makes fairly simple translations possible if I use the KEEP PEN INDEX NUMBER translator both ways.

As I am not an AutoCad user, forgive me if I sound like I am talking out of my a**, I am. But I am just repeating common complaints about my 'inferior' ArchiCad DWG export, and I'd like to get to the bottom of all of these issues. Your thoughts, elucidations are valued. Thanks in advance!

Thanks for this initiative, Andyro!

Edited:
I should add that being a compulsive Plotmaker hater, my experience mostly comes from exporting from Archicad to model space for consultants.

[Andy Thomson]

Thanks for the ray of Stockholm sunshine 😉

I will see if export units as 1" = 1 drawing units solves this, but I suspect not. It is when units are changed from decimal feet to fractional inches (in AutoCad), so that rescaling is required, don't ask me why. 1'-6" is the same as 1.5' if you ask me. It enters autocad at 1:1. I am asking how to export with fractional inches, rather than decimal feet, so it is a different issue than a question of units or scaling.

The issues with messy flattening for autocad (lots of unexploded junk, redundant linework and fills, and blocks) - is more of a wish. There is no workaround for this afaik. Ideal would be on the ArchiCad side:

1> exploding ALL blocks except furniture and possibly windows/doors.
2> flattening, then running a 'check and purge duplicates' filter/apx, then..
2> 'unifying' grouped linework of same pen+layer as polylines (to make working on this stuff further in AutoCad relatively painless)

As for pens, I wish I could get the kind of bylayer export our partners expect.

What I am after is the kind of export that our parnters in architecture can continue to work on, as we often see models 'exploded' in late DD to be turned into CD's by other firms using autocad, and they are hating me/ArchiCad and working with us because of crummy DWGs.

I'd like to differentiate my ignorance from ArchiCad issues here.

[Anonymous]

We noticed that many times the scale in the dwg file is right, but AutoCAD units are set to decimal inches instead of "Architectural" (feet and inches.) Simply opening the dwg file in AutoCAD and changing the units to "Architectural" often solves the problem.

Changing the units in Architectural Desktop is tricky because when you type UNITS to check the settings, they usually already say "Architectural" when in fact they really aren't. Clicking Apply will reapply the "Architectural" units so that the drawing reads right.

As far as we know, there is no way to make the translator choose "Architectural" units instead of decimal inches. If someone knows how to do this, please post it here!

[TomWaltz]

andyro wrote:
Thanks for the ray of Stockholm sunshine 😉

Or Stockholm Syndrome, perhaps...

[Anonymous]

Hi,

Our firm is multidisciplinary with Architects working in Archicad, and Structural/MEP engineers working in Autocad based products.

Our setup is that the Archicad translator is set to explode complex elements, and exports all colours/linetypes ByLayer.

We also direct some special Archicad pens to specific Autocad layers to avoid having too many layers in Archicad.

The translator also refers to a template DWG file which has all the standard Archicad layers included, with the corresponding colour/linetype/linethickness set correctly. It also has the units variables set to millimeters to stop drawings opening in Autocad as inches.

This setup seems to work fine for us, only new "non standard" layers that the Archicad user adds to the project come through with colour/linetype/width set to white/continuous/default.

Perhaps you could ask your partners to send you an example file set up how they want it, and use that as a template.

[Anonymous]

I think the Translator works quite well. We have to remember that this is an application exporting to a file format which is not its own! And that dwg is the most conservative file format because it belongs to the most conservative CAD application! This is an application that still has problems to use Windows fonts!
We have to be thankful there is a Translator at all! And I am frustrated that every AutoCAd user expects me to send him the drawings in dwg! Because he uses AutoCAD and I have to adapt to his way of work! When will I be able to ask for drawings in pln?!?

P.S. I have never had such problems with Engineers who use Allplan. Perhaps it is a matter of education? And humbleness?

[Andy Thomson]

kliment wrote:
When will I be able to ask for drawings in pln?!?

Perhaps when US currency is no longer the international standard?

[Djordje]

andyro wrote:

kliment wrote:
When will I be able to ask for drawings in pln?!?

Perhaps when US currency is no longer the international standard?

Ever heard of Euro? 😉

[Andy Thomson]

There is hope!