Issue with Importing DWG

[bailey80x]

Hey, 

I'm trying to import a dwg file but i'm either getting a message "Failed to open file, could not open file" or it crashes and i have to restart the software. 

I'm using the latest version 2.5.7 but this was happening on previous versions.

I've attached the dwg. 

thanks

 

GA_plans_Warford_ (1).dwg

[Gnobelix]

Hello @bailey80x

Welcome to this forum.

I can confirm that Designer crashes when opening this file.

The file seems to be corrupted because I cannot open it with any CAD program.

Which program was used to create the file?

Cheers

[lacerto]

You probably get the best results if you can export your drawings in PDF format from the CAD application itself. I do not think that there is necessarily anything wrong with your DWG file, since the fact that Affinity Designer crashes when it tries to open the file is not an indication of anything else than poor quality of Affinity DWG import filter.

I opened your file with Illustrator CC2025, CorelDRAW 2023 and QCAD, and while none of these apps is a professional CAD application, none had issues in opening the document, but there are many options to be chosen at import time, and missing fonts, etc., so there is significant variance in interpretation of the drawing, depending on the app used, but I hope you have some use of the PDF exports made from these applications when trying to open them in an Affinity app:

GA_plans_Warford_ Illustrator_CC2025.pdf

GA_plans_Warford_ Corel2023.pdf

GA_plans_Warford_ QCAD.pdf

[Kevin B]

Hi All, 

I'm dropping this question here since this is the most recent topic related to CAD, and I'm no expert on the topic myself. 

I want to know if there is any difference in the simple visual content, between 1) importing / opening a .dwg file directly into Designer, and 2) import / open a PDF that was published / exported from the same .dwg file and application? 

In Designer, I need to import and work with only what is visual and nothing hidden in the file like dimensions, simplified and repurposed for training instructions. It would not be exported back to .dwg format or enter the CAD workflow in any way. 

I was thinking that I would have a more pure conversion to .afdesign format if I avoided the PDF stage, but that is something that I made up and possibly (probably) isn't not valid. Perhaps, regardless of the process, Designer is going to put it all in its own format and I probably wouldn't see any difference. 

Like @lacerto wrote above about the Affinity DWG import filter, I have not had much luck opening that filetype and gave up on it all. If a PDF is all that I need then much simpler as I don't have to ask the CAD author for a copy of their .dwg -- they don't like to hand those out to just anybody. 

Thanks for your input on this, any suggestions are appreciated. 

Kevin

 

[lacerto]

Since layer-related information is very often important in CAD files, and PDF as a file format is ill-suited for transferring that kind of information (it is possible but basically relies on custom / app specific implementations, e.g. Illustrator including this kind of information by embedding an AI file within a PDF shell, or Affinity Designer using OCG layers in a specific way), delivering a .DWG file (possibly limiting the content specifically for export purposes) is often the best choice.

If a CAD application could create an AI file, layers and probably some other native features could be included in the exported file, as well, but as far as I know, e.g. AutoCAD only supports .WMF and EPS as vector-based export formats (and PDF only as a kind of output format, rather than a specific export format), and they are both quite limited file formats. Some CAD apps might also be able to export in SVG format, but that does not support layers, either.

[Kevin B]

Hi Lacerto, 

Thanks for your quick reply and good information. Ah yes, I should have mentioned layers and if I need them or not. Basically not needed because the layers that the CAD authors create are aimed at the construction aspect (ship-building here) and of no relevance or benefit to my work. Usually a layer contains objects that I do need and other objects that I don't, so I simply have to delete manually what I don't need. A bit of remaining clutter is not so detrimental, my annotations and symbol overlays stand out well enough for the viewer to see, and they just disregard the background bits. 

The CAD authors will not do anything specific for my work, I'm in another later work-flow that they aren't responsible for, I can't even contact them directly. 

So if layer import is not necessary and no CAD processing specific to me is available, I suppose a simple PDF converted to .afdesign is sufficient, and really maybe I don't have a choice. 

I hope that Affinity can improve their .dwg import process for all of you that really do need that capability in your work. 

 Thanks again for your assistance, it's much appreciated. 

Kevin

 

[lacerto]

Hi @Kevin B -- yes, if layers are not relevant and saving / printing to PDF retains vectors, I think the PDF is the way to go. You could also try if EPS exports (or .WMF, if you are on Windows) make sense in certain cases, but Affinity apps generally open PDF files quite well, so that would be the first choice.

DWG import filter of Affinity apps is indeed very elementary. You can test its capability by trying to open these AutoCAD sample files:

https://www.autodesk.com/support/technical/article/caas/tsarticles/ts/6XGQklp3ZcBFqljLPjrnQ9.html

One possibility could be getting a low-cost CAD app and export from there:

...which, when exported to PDF from QCAD, opens in Designer like this:

This is much better than the DWG import by Designer from the native AutoCAD file, which is this:

 

 

[Kevin B]

Thanks very much @lacerto for your valuable input, I will work with PDFs from the CAD authors as there's really no visual difference that would affect my work. Like you wrote, Affinity apps import and convert PDFs very well so I'll work with .afdesign format and export to PDF or SVG as needed. 

Regards, Kevin