Hi,

I'm often working with files that were created in AD Inventor and then exported in the IGES format. The file sent to me today was in a zipped format at just 3MB in size. Unzipping it gave me a 32MB IGES file which I was then able to import (very slowly) into MoI. I saved this file without any changes using the 3dm format and was surprised to see it had grown to over 174MB!

Why does this happen? Is 3dm an inefficient file format? Where did all the extra data come from?

Mark