Save as DXF increases file size dramatically???

[james 172]

Hi all

Haven’t been on here for a while but have recently started a new job and am having some issues when converting a dwg to dxf.

I have a dwg which is around 300kb but when I save as a dxf the file swells to 2-3mb sometimes more.

I have used PURGE, -PURGE, FILTERS to remove everything possible but it still bloats the file size when I save as dxf.

Does anyone have any ideas as to the problem?

Thanks

[ReMark]

I thought that was normal (i.e. - saving as a DXF file increases the overall file size).

[eldon]

And if you zip a DXF file, it shrinks to smaller than a zipped DWG file

[irneb]

Yep, the DXF file is a text file with lots of waste in it. E.g. instead of a number (say 2,147,483,657) being saved in binary format in a DWG as 32bits (i.e. 4 characters in length) it's saved as a string of characters (2147483657 - 10 characters long). This is just a small increase in what usually happens to DXFs.

 

The reason a DXF zips to something smaller than the original DWG is that Zip works a lot better with text files than binary files. The DWG is already in binary and the Zip then has trouble trying to compress that as efficiently.

[rkmcswain]

The DWG is already in binary and the Zip then has trouble trying to compress that as efficiently.

 

Plus, DWG files have been internally compressed since the 2004 release.

 

http://www.caddigest.com/subjects/autocad/select/grabowski_dwg.htm