[CE U17] Converting sheets to DWG

Hello,

I think this is a very general question, I tried searching the forum for similar threads but couldn't find any. Let me try to phrase the question:

Our clients request all As Built documentation to be delivered in PDF and DWG. They won't accept DGN because Microstation / Openbuildings Designer / ProStructures (the softwares we use at our company) are simply very little known or used in our region. So that means I have to convert all sheets to DWG.

Unfortunately though, I can't find a good setting to create well structured DWG file. What I would like to achieve is a single DWG file for each sheet where the geometry, annotations, ... from the (DGN) drawing models are placed in the model space and the layout contains viewports. The way it would be if I created the drawing in AutoCAD for example. Other software like Revit and Tekla Structures do this in a good way, in my opinion.

The best I can achieve from Bentley products, without having to use XREF to external files, is to use the option to "merge" references. But this means that all geometry will be drawn in the layout/paperspace of the DWG file and model space will remain blank. This is unacceptable.

I can imagine one of the difficulties is that DWG only supports a single "Model space", which would correspond to the design/drawing models in a DGN file. And one sheet usually references multiple of those models. 

The other softwares I named above handle this by placing all the geometry side-by-side in the model view, then creating the relevant Viewports in the layout. A much more elegant solution, meaning mostly that one can simply measure in the model space without worrying about scale etc.

As it happens I just got a question from one of my colleagues related to this exact problem, while I was typing this post. So I'm 100% certain that we are not the only people struggling with this, there must be others, architects, ... who have the same issue.

Is there a solution for this? Or would it require a big amount of rework for the DWG exporter to create such functionality?

Parents Reply
  • If your goal is to put your sheet into modelspace, you may try following steps:

    1) Activate your sheet model from which you intend to recompose the drawing

    2) Set MS_DWG_SINGLESHEET_AS_MODELSPACE=1 to tell MicroStation to map your sheet to modelspace, as supposed to a paperspace, when the source has no design model

    3) In DWG SaveAs Options select a view you like

    4) Toggle Advanced->Create Separate Files for Sheets on

    Save your DGN as DWG into a clean folder, find a file created from your sheet.  This file should have geometry in the modelspace.



Children
  • I think the real question is how convert a DGN which has a Design Model, Drawing Models, and associated sheet models to some sort of DWG that retains the association between the drawing model and the sheet model. Since DWG doesn't have sheet models, those get saved off as separate DWG files, but they don't include the sheets - those stay as layouts in the "original" DWG.

    Case in Point. OpenRoads Cross Section sheets. There is a Design model, which has all of the relevant design drawings referenced, through which the section views will be cut/projected. Named Boundaries generate Drawing models, which contain the section view through the Design Model, which are referenced into Sheet models. The sheet models are directly dependent on the Drawing models, not the Design model.

    There is this discussion thread about ORD DWG conversion which might have information useful to other verticals.

    What I suspect Johan may be looking for would be a way to translate the file so that whatever is referenced into the Drawing Model is merged in (or maybe kept as an Xref?) so that the Drawing Model becomes the Modelspace, and the associated sheet becomes the Paperspace.

    Putting sheets into Modelspace isn't always useful, as often references have been scaled up or down to fit properly on the sheet border, which makes them entirely the wrong size for the real world. Nice to know how to do it! But I can't see myself using it often.

    MaryB

    Power GeoPak 08.11.09.918
    Power InRoads 08.11.09.918
    OpenRoads Designer 2021 R2

        

  • I think the real question is how convert a DGN which has a Design Model, Drawing Models, and associated sheet models to some sort of DWG that retains the association between the drawing model and the sheet model.
    What I suspect Johan may be looking for would be a way to translate the file so that whatever is referenced into the Drawing Model is merged in (or maybe kept as an Xref?) so that the Drawing Model becomes the Modelspace, and the associated sheet becomes the Paperspace.

    Exactly, well phrased! I'd go for the merging (not Xref, it's always a hassle in my experience when sharing with external people).

    Putting sheets into Modelspace isn't always useful, as often references have been scaled up or down to fit properly on the sheet border, which makes them entirely the wrong size for the real world. Nice to know how to do it! But I can't see myself using it often.

    I totally agree, but you might be surprised how many drafters (in Belgium) work this way. It can get very confusing when using the "measure" tool on a detail that's on a different scale from the main drawing. Huge mistakes can be made...

    Actually that's what I like so much about the DGN approach with Model => Drawing => Sheet. In AutoCAD there is always the difficulty where to put annotations and dimensions. In theory it should be done in the paperspace, but it has certain disadvantages. Using the "Drawing" in DGN as an intermediate step is really a good solution! One that is very similar also to Revit's 2D views as well.

  • What I suspect Johan may be looking for would be a way to translate the file so that whatever is referenced into the Drawing Model is merged in (or maybe kept as an Xref?)

    Not sure if this will help, but 17.1 introduced a Merge Internal Reference option. If I understand the vid properly, this merges any internal Model files into the Sheet model.

    Maybe the same tool can be used to merge any clipped, scaled etc References into the Drawing Model; and the new Drawing model can then be referenced in the Sheet model before exporting to DWG?

  • what  I have done in the past  is use the export  to DGN with merge refs option to a new  folder so I keep originals then I open one of these new DGNs with the merged xref and  then export that to another  new folder  batch process with export to DWG  and this works for me when i check in dwg I have a model space and  a paperspace which has the layout xrefed through the model space to the view port .. I have had to do this for as builts to  DoT Rail many times in v8i and it works  albeit  have to do 2 times

    Lorys

    Started msnt work 1990 - Retired  Nov 2022 ( oh boy am I old )

    But was long time user V8iss10 (8.11.09.919) dabbler CE  update 16 (10.16.00.80) 

    MicroStation user since 1990 Melbourne Australia.
    click link to PM me 

  • Hi Lorys,

    Thank you for the valuable tip! It works perfectly for the situation when there is 1 drawing model and 1 sheet model.

    However I also have quite a few sheets where there is more than 1 drawing model linked (floor plan + some details, ...). I tried the same workflow for one of those files and that doesn't work, unfortunately. Did you have that situation as well? How did you solve that?