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?
Johan De Cock said: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.
For this case, I recommend you directly use DWG format rather than DGN format. MicroStation natively support DWG file format.
Thanks for your reply, but that's not a solution. Like I stated I am using Openbuildings Designer and ProStructures. I'm quite certain they don't work in DWG mode.
Anyway, even in plain Microstatoin, it would defeat the purpose of using MS, wouldn't it? In that case I could just as well draw everything in AutoCAD.
Different file formats have their own concepts. Except your mentioned DWG can't support multiple design models, DWG has not drawing model concepts. If you simplify your DGN only contain one design model and multiple sheet models(every sheet model references a saved view from design model), then converting to DWG will keep well.
Well, that's not a solution. We need drawing models when going from 3D to 2D.
I'm not even sure if the method you propose would work in OBD or PS. Both software do some kind of resymbolisation in the Drawing model.
I don't believe it would work for OpenRoads Designer either - those rely on Drawing models to generate profiles and sections for sheets. There is no "model space" representation of either profiles or cross sections.
I suppose a workaround might be to create drawings where you could reference your drawing model into the empty design model, merge it to master, and import your sheet model. You'd probably have to drop the intelligence of everything, but since it is a one-way drawing solely for submittal, it may do. Unfortunately, depending on how many plan sheets (and corresponding drawing models!) you have, this could be time consuming and labor intensive. There is probably a way to automate through programming, maybe, if you have or can pay someone to write it.
The forced use of drawing models in vertical product sheet production really throws a wrench into any file sharing with DWG.
MaryB
Power GeoPak 08.11.09.918Power InRoads 08.11.09.918OpenRoads Designer 2021 R2
Remember that Drawing models export to DWG as model space so technically separate DGNs with one Drawing model and Sheet model would export as a complete DWG "system".
If you were to set up your dgn files to use external attachments for the source design model and a single dgn per drawing/sheet. You could technically then get the export to retain your external reference and convert it (for the design xref) and then the drawin/sheet would be exported as a DWG with the drawing model in model space and the sheet in paper space.
This is probably the best you can do with the limitations of DWG format.
Regards,
Mark
OpenRoads Designer 2022 R3 (10.12) | Microstation 2023 | ProjectWise CE 3.4
Thanks Mary and Mark for the replies.
As long as there is only one "drawing" on each sheet, I think this workaround would work just fine. But that's really the issue. I have a 'plan' view on each sheet and then some sections, details, ... In DGN these are simply different drawing models. But as stated DWG can't contain more than one.
Currently I already have a separate DGN file for each of my sheets where I reference all the drawing models from the original DGN into one single drawing model. Then I can export a DWG containing all the "geometry" in a single model space:
For the "model space" this works OK. But I don't have a link with the sheet model. Maybe I could indeed create a sheet model in this file. But as Mary says, it would require quite a bit of additional work. And it's not something I look up to ...
The reason I ask here on the forum is to know mostly how other users deal with this. Or don't you have to deal with it for some reason?
As I stated in my original post, we came across the exact same problem in files that we received from an external organization. It appears they also are working with DGN. The result for that project were DWG files with all the geometry in the sheet model / paperspace. It's unusable from our perspective.
Other software, like Revit, deal with it by doing more or less the automation that Mary described above in the background. They don't treat the DWG file as a design file, but rather as an export/deliverable like also PDF and IFC files are. I think that's the problem with the Bentley approach. They try to keep as much as possible the compatibility and treat the DWG as an equal version of the design file. But that's not necessary. We are happy with a "dumb" version of the DWG that looses any association with the original design file.