file format differences

[Anonymous]

I have been asked by one of our engineers if we can set AutoCAD to default to save in earlier file formats.

However, before I do that I would like to understand the diferences are between the files.

What differences are there between the different file versions of DWG files? eg 2013, 2010, 2007 etc.

What would we be losing by simply saving all our drawings to a very early version?

Cheers

Kenny

[Alfred.NESWADBA · Accepted solution]

Hi,

>> What differences are there between the different file versions of DWG files? eg 2013, 2010, 2007 etc.

The DWG file format is not public, so at the first point of view only Autodesk developers have that info.

There is one site >>>click<<< from different members trying to be compatible with DWG format, maybe you can get there specific informations.

>> I have been asked by one of our engineers if we can set AutoCAD to default to save in earlier file formats.

My opinion to that: never ever 😉

Besides of performance issues (destroying objects to make them available for old AutoCAD releases as well as "healing" them to get them back to current state when opened with current AutoCAD) you might experience sometimes file-defects (objects that are defect then).

So I would never save back files I'm working on, if anyone else needs files I created with current AutoCAD I would create a copy of my file in an old format or the partner needing my files in an old format can use >>>Autodesk Dwg TrueView<<< to open my current file and create a copy in the old format by himself.

>> What would we be losing by simply saving all our drawings to a very early version?

All geometry types not available in that old AutoCAD releases are converted to "compatible for visualization" objects and the older the DWG format the more objects are converted. That depends especially what types of objects you are working with. But even the simple object like a LINE might have issues if you used something like e.g. transparency. There is no list available which object changes it's properties/internal data-structure when saved back. But the older the format is the more problems you'll get with that.

My last words to that: save back only copies of your files, but never your working file.

- alfred -

[imadHabash]

Hi,

yes you can set your autoCAD to save your drawing in earlier format from OPTION command line (see attached)

regarding differences between versions for DWG . The DWG format of AutoCAD drawings is regularly updated after a couple of releases. New AutoCAD release always supports reading of all older DWG file formats and writing of some older DWG formats. and as you know softwares -generally- always improve to follow new technology for hardware and programming languages. AutoCAD as one of these always make changes and improvments to walk with these technology and to improve the performance for the user and software it self.

it's a long story to discuss ... BUT anyway Thanks for your good question.

Good Luck..

[jggerth]

to quote Alfred...

"My last words to that: save back only copies of your files, but never your working file."

This is important.  Depending on how far back you go, you lose capabilities and can increase file sizes.  As well, if any verticals have been used, the inormation in the AEC objects is not backwards compatible.  Even if the dwg foirmat has not changed, the AEC information may, and mau be incompatible/unusable in earlier formats.

Save back when you absolutely need to, but that should never be your default.

[pkolarik]

Kenny,

All of the above is good information to know. Yes, there are changes from versions to versions that may have affects from saving backwards. Yes, there is always the possibility of even more incompatabilities if you're using a vertical product.

That being said, until about 4-6 months ago (when everyone in our office finally got on 2015 versions) it has always been standard practice in our entire office to save back to the previous file format version. We've has this practice in place for as long as I can remember (been here a looong time now) and have never had a single issue with any of the content of the drawing files.

The reason we had to do this is most times the consultants we send files to/work with have been on slightly older versions of autocad than we have (mostly not the case anymore these days).

They've never reported any issues with our "saved-back" files, and we've never noticed any issues on our end with saving the files back one file-format version (i.e. - saving 2013, 2014, 2015 files back to 2010 format).

Every now and then we'd run across someone using a really old version and we'd use the "export to autocad" feature (we run vanilla, c3d, aca, mep, and electrical versions in-house) to explode everything for them, but that's it (and that has nothing to do with what file format we're saving back to)

[Anonymous]

Thanks for the responses.

I think for the moment I am going to keep saving into the most recent version and only back save when necessary.

cheers for the input.

Kenny