drawings ballooning in size

hiya

saved a couple of 2009 drawings back to 2004 in Trueview. the files were originally around the 5meg size but have now growen to 45meg!..any ideas why this would be the case or how to sort it

cheers

The culprit here, or at least one culprit is that you are saving to an older format.

I can't tell you why, I'll leave the technica mumbo-jumbo to someone else - but in my mind, AutoCAD have evolved it's file-saving technique from 2004 to 2009, so the files are smaller now than they where then. That's how I see it, might be complety off the wall.

As far as I know, you can't sort it. You can not save it to 2004, that would be one way. If you have done purge and audit on the files, and removed all unnecessary things, then you can't really do anything more

Files do inflate during normal use, I assume with "undo" information etc.. Often you can do 2 consecutive save and exits and see a dramatic reduction in size despite having done nothing.

but in my mind, AutoCAD have evolved it's file-saving technique from 2004 to 2009, so the files are smaller now than they where then. That's how I see it, might be complety off the wall.

Here are some things which can cause file bloat:

1. Scalelists

2. Layer Filters

3. Layer States

4. Objects which are Annotative

Following on from what Tiger said above, try to ensure that if you use any of the list above, keep them to the absolute minimum when sending out your files.

So from what NBC says, if you have lots of stuff that was introduced in 2009 or 2008 in your files, and then save it down to 2004 - then the file size should increase much much more than if you have a ordinary line-n-circle drawing with nothing else.

that's the way I see it too, so if you are completely off the wall, I'm there with you.

Always nice to have company, even if it's the wrong wall

So from what NBC says, if you have lots of stuff that was introduced in 2009 or 2008 in your files, and then save it down to 2004 - then the file size should increase much much more than if you have a ordinary line-n-circle drawing with nothing else.

Tiger, you were also 100% correct in your first assumption. 2004 saw the introduction of techniques to save your drawing to a smaller file size - albeit not a great improvement, it did make smaller files. 2007 then made even greater advances with compression of the files.

So, your original comment teamed up with the other comments mentioned in this thread have combined to produce the larger file size. One thing to be aware of though is that the smaller file size does not equate to less usage of memory in your computer once you've opened the drawing. The smaller file size is the result of a ZIP style of process and once you open it, the drawing still uses as much RAM as it would have in the original versions (i.e it'll use less disk space, but the same memory once opened).

Going from 5MB to 45MB is a bit over the top though... I'd recommend that the drawing is Audited and Purged, Saved, Opened and saved again. Here's why:

AutoCAD drawings are actually a form of database that can't remove references to objects out of the middle of the file. The first stage (Audit & Purge) will make sure there are no corrupt or unused objects. Saving, reopening and saving again will clear the drawing database of objects that may be flagged as being erased (but still listed in the database).

Basically when you delete something out of the middle of the database, AutoCAD can't just 'pull it out' and just flags the object as being deleted. When you save the drawing, the flagged object is retained. When you reopen the drawing, the flagged objects are ignored and only the live ones are written to memory. Then you can save the drawing without all the deleted objects from the previous session...

Hope that helps you understand why AutoCAD's Drawings can change so rapidly in size without any apparent reason...