Revit 2018 DWG Export issue

[Anonymous]

Hi guys,

Just wondering if anyone out there is having some issues with Revit 2018 exporting to DWG files?

It used to be fine when I have used 2017 to export, however, now that I have upgraded the model and revised my sheets, it took almost forever to export one single sheet. During the export, the memory process rose used to over 15gb at some point. Current working file is on 50mb large.

I am working with generic models that contain theme park props with complex forms generated in 3Ds max and transferred into Revit and Revit structural steel members (along with Structural Connections from 2017) for support. 

Failed tries:

1. Exporting into other dxf files

2. Running in high priority mode and older stable system compatibility

3. Purging all files and re-exporting

CPU Specs:

Windows 7 Professional 64-bit Operating System

HP Z420 Workstation

Intel(R) Xeon(R) CPU E5-1620 0 @ 3.60GHz 16GB RAM Installed memory

Please help.

Warm regards,

Jason

[ennujozlagam]

@Anonymous hello, try to audit your file and install latest updates for Revit 2018 maybe could fix your issue and see if helps. thanks

[Anonymous]

Hi @ennujozlagam

I have tried that too. It didn't work so far =(

When first installing, I have already made sure all the latest updates are installed. Especially after learning it the hard way from Autocad moments in the past.

[Anonymous]

bump

[Anonymous]

UPDATE:

I have managed to figure out the issue myself despite having no solution still.

Apparently there's an issue when complex mesh linework is involved.

Revit 2018 seems to have more trouble than 2017 trying to flattening those 3D mesh lines.

Please fix this as it is quite a big issue for larger scale projects.

Very concerned as this is an official job where I have already converted my files into Revit '18 but unable to provide official DWG documents.

My company has a number of licenses registered but I am just using my own account for posting on this forum. I hope official administrators could jump in to assist this.

[Viveka_CD · Accepted solution]

Hi @Anonymous

I see that you are visiting as a new member. Welcome to the Autodesk Community! 

• Please click HERE for the link which describes features that need to be addressed during an upgrade.
• Some new and changed features of Revit 2018 result in certain behaviors for upgraded models. Review this information before upgrading your models.
• You mentioned about the long duration to export one single sheet - I recommend that you minimize the size of your Revit® files in order to optimize project performance.
• A critical factor in the speed and performance of your computer is the amount of Random Access Memory (RAM) that is installed.
• Since you memory process >15GB, looks like you need to change your virtual memory settings. See HERE for more information

Let me know if you have any questions.

Click on the ‘Accept as Solution’ button if you found this post useful and help users identify similar solutions for their issues. Kudos are welcome!

[Anonymous]

Hi @Viveka_CD

Thanks for the list. That will help me in the long run. 

There's no use crying over spilled milk as all I am trying to do now is exporting it to CAD. Regardless of whether it's 2017 or 2018, it SHOULD perform its tasks of exporting to DWG because that is the most important function of all since no other third party programs are available to help out with this dilemma. Especially when the consultants are still using AutoCAD for the job. MY file sizes have been optimized to be very lean and mean @ 50MB. This shouldn't cause an issue when my 2016 are working on files which are larger than 500MBs and still able to export dwgs. 

I will give the memory process change a try and hoping it works but currently my export is still running in the background with what's left of the memory for 2 hours.

Also, I am hoping to know if there are any recent updates that addresses this issue that I am having.

Once again, thanks for the help. I really appreciate this 

[Anonymous]

Please check on this again. I've tried all of the above but still no solution.

I have tried exporting over the weekend and not ONE sheet was converted to dwg.

Frustrated as this is a job with actual clients and this affects my submission.

[Anonymous]

I have managed to resolve this issue.

None of the above solution helped. 

It seems like Revit 2018's exporting capabilities have been limited due to (I assume) a lot of the new features be it structural connections etc while Revit 2017 exporting function works better without the new features. I assume this needs to be looked at. 

While the new 2018 solves quite a number of problems 2017 has, being able to export CAD drawings with heavy linked files need to be prioritized I hope. 

[Viveka_CD]

Hi @Anonymous

Glad to hear that you managed to resolve your issue. Sorry that it took a while to get back to you.

I recommend that you look at the following link to modify a dwg export setup.Click HERE

Click HERE for general options to specify settings for DWG/DXF export

Before exporting a Revit model, limit model geometry to improve the performance of the export process.

However, It is important to keep an eye on your virtual memory settings. See HERE for more information

REVIT 2018 has enhanced features apart from using geographic data from a linked dwg

Thanks for your suggestion to prioritize export options for heavy linked files.Please note that we always welcome feedback to improve workflow.

Tell us what you think about our products and any improvements you would like to see HERE

If you looking for a feature to get implemented, I suggest you post your idea at the Ideas-page

Please mark this response as "Accept as Solution" if it answers your question. Kudos gladly accepted.

[Viveka_CD]

Hi @Anonymous

Please note,I have unmarked the reply, since it is not the solution. Since you mentioned that you have managed to resolve the issue, did you optimize the model and implement certain settings that you can share with the community? This will benefit many users seeking similar solutions.

Thank you.

[Anonymous]

@Viveka_CD

The solution I had was downsizing the CAD 3D model import from about more than 10mb down to roughly 2mb or less. 

That way it actually completes the export which is frustrating because some of the quality or shape of the 3D had to be compromised whereas Revit 2017 could perform the task.

Having said that, after exporting it, I've encountered a couple more issues:

1. Missing structures that were within the 3D model
   hypotheses - I'm guessing having transparency caused it to not export when the structure is deep within the model
   solution - had to export the sheets twice with and without structure and superimpose both
   
   
2. Viewports on the sheets had been zoomed out and had the wrong UCS showing nothing in them
   - had to manually fix in CAD which caused more time loss
   
   
3. All transparency settings set up on the sheets are lost after the export.
   - nothing i can do as they have been all flattened to lines

I do not know if this can be considered as a solution but I hope this helps other users and that autodesk will fix this issue.

[Viveka_CD]

Hi @Anonymous

We wanted to check back in with you on this post. How is everything working out? As mentioned before, I would be happy to take a look if you would like to post a sample file for troubleshooting. Please let us know if further assistance is needed from the community on this post. We are happy to help wherever possible. Thank you and we look forward to your reply update.

[Anonymous · Accepted solution]

@Viveka_CD

Yeah that was annoying. I had posted a reply earlier about this and somehow it was lost after editing it.

Having said that, the way I resolved this issue was to downsize the 3D Cad model from 10mb+ to 2mb-ish.

It is very weird as 2017 could export those files but 2018 could not.

Post export, there seems to be further issues that arised:

1. Viewports on my sheets were zoomed out and UCS was reset
   - had to reconfigure the entire sheet in AutoCAD
   
   
2. Missing structural framing within the transparent 3D model
   - identified that it only happens if the structure is deeply embedded into the transparent model
   - had to export the affected sheet twice with and without the 3D model and superimpose both
   
   
3. Transparency abilities are lost after export
   - cant resolve this as everything was flattened

I hope this helps anyone else who's having issues with this situation. I have spent way too much time on troubleshooting this myself.

Conclusion is.. Autodesk needs to look into the export capabilities of Revit 2018 and hopefully provide a patch that fixes this issue.

Also, there's a confidentiality disclosure that I am bound to so I can't send any files over unfortunately. 

Jason

[Viveka_CD]

Hi @Anonymous

No worries, both your messages are saved and I hear ya

Great to hear that downsizing your 3D Model from 10MB to 2MB helped resolve the issue! As recommended earlier before exporting a Revit model, it is highly recommended that we limit model geometry to improve the performance of the export process. 

I also suggest you take a look at the model performance technical note HERE

It is likely that you will experience loss of data during an export.

Since you mentioned a few issues related to loss of structural framing post export, it is recommend that you modify settings on your Solids tab as follows:

1. Open the 3D view of the project to export.
2. Click File tab ExportCAD Formats (DWG files).
3. In the DWG Export dialog, click (Modify Export Setup).
4. On the Solids tab of the Modify DWG/DXF Export Setup dialog, select Export as AutoCAD Architecture and AutoCAD MEP Objects.
   Note: This option and the Prefer drop-down referenced in the next step are only visible if the ExportACAObjects key is present in the Export section of your Revit.ini file and is set to 1.
5. If you want the exported DWG to keep its structural properties intact, select AutoCAD Architecture objects, on the other hand if you want to maintain the geometric accuracy, select geometry.
6. Regardng your zoomed out viewports, please try changing the UCSFOLLOW system variable setting to '0' in AutoCAD

I understand that Revit 2017 export capabilities worked fine for you compared to Revit 2018. We will test export capabilities in Revit 2018 and troubleshoot for errors.Thank you for posting about this issue in the forums. I have logged this issue with the development team for further investigation. Please do not hesitate to reply to this thread with any additional questions you may have in regard to this issue or any message that you want me to share with development that we haven’t already discussed.

You are also welcome to contact the product team directly. If you have additional comments specific to the software or its functionality for future consideration, please use the Product Feedback page. How to provide feedback on Autodesk products goes into more detail.

Please accept as solution if my post fully solves your issue, or reply with additional details if the problem persists.

 

Good luck with your projects!

[Anonymous]

Hi @Viveka_CD

The problem still persists with the results of the export despite all the steps you've mentioned being taken.

One of the viewport remains zoomed out and ucs set to world value.

Steel frames still disappearing once exported if it is still covered by a transparent generic model structure. Having said that, exporting to ACAObjects created more problems as the steel frames do not retain its cross section angles and all beam/column joins will be lost.

I think the transparency will never be shown if the exports are from sheets. Only 3D views

Do send me a mail if the bug is fixed and there's a release patch for this. 

Thank you!

Jason

[Viveka_CD]

Hi @Anonymous

I would be happy to take a look further into the issues that persist, if you would like to post a file for troubleshooting. 

Let me know if you have questions regarding sending the file.

Thank you and we look forward to your reply update.

We are happy to help wherever possible.

[Anonymous]

Hi @Viveka_CD

Sorry it took awhile for this reply.

Because it's an intellectual property i cant send any files.

Please see the images below for some of the exporting issues.

I hope this is enough for you to proceed to fix the issues.

Regards

Jason

[Viveka_CD]

Hi @Anonymous

No issues if you cannot send the file. We will re-create the issue and test. Thanks for taking the time to send the images. I'm trying to understand the images and the discrepancies. I know you mentioned Steel frames covered by a transparent generic model structure. Can you please label the parts/layers in the images for clarity and resend?  

Regards,