3DM : 2,7MB, OBJ : 170MB, why?

I have made a simple door, for a new architecture model, and duplicate many time with a bloc definition. The 3DM file has a size of 2,7MB.

The model is very simple :

Exported as OBJ (mesh and less polygons as possible), the file has a size of 160MB. It’s just a part of a big 3DM file… Is this possible to reduce the size or is this normal ?

Jerome

Hi Jerome -

As block instances are not exported as instances to the OBJ format, I would say that this is normal behavior for scenes with a lot of identical objects like that.
-wim

Hello,

Just a thought - you have lots of slender elements : if you allow high aspect ratios in your mesh or export as nurbs objects then you may have a smaller file size …?

Graham, probably but It seem Twinmotion 2020 I used as renderer do not import obj file with nurbs object. Somebody can confirm this ?