Reduce model size of imported STP file

I have imported a STP file of a small engine for a client that I need to design several parts for. Having imported the file into Rhino, the file size is 420mb, which really slows down my workflow to an unmanageable level.

Can someone please suggest a way to help me reduce the file size so I can work on this and still retain the necessary information so I can export to Keyshot later.

Thank you!

Well, ReduceMesh can do a pretty good job of reducing mesh size (for rendering,) you just have to be careful not to overdo it.

Best thing would be to split stuff onto layers. Easiest way to do this is actually at the export end - if possible have your client export the model into multiple files, organize as needed. Otherwise you have to manually sort things into layers on your end, which is a total pain. I feel you…I’ve had 1 gig of geometry dumped off on me like this before.

Hi Keenyana - Does the thing come in as a single block instance? If so, you can ExplodeBlock, Purge (block definitions) and then go about deleting the parts you do not need or split it out into separate files.


Thank you for the responses so far . . .

JC - I have never used ReduceMesh, but I still want the geometry there in Rhino. I have several iterations of parts to build over the STP geometry. is ReduceMesh for rendering or still working on the file?

Skyg - I have already done the arduous task of separating it all into layers, for sure, noted for next time . . .

Pascal - It came in several block instances and polysurfaces. I exploded the Blocks and sorted through all the surfaces to work them back into polysurface parts or grouped surfaces that didn’t want to join. that’s how I got to where i’m at and when I saved - 420mb. chug chug chug . . .

So is ReduceMesh my best bet from here? do I select specific parts and use that command specifically on them individually? any other ideas?

Thank you all!

Oh, STEP file, I thought we were talking about meshes. Nevermind!

What are your mesh settings set at? Making sure that less polygons are created for display will speed things up.
Also, extracting the render mesh and only showing this when working on a single NURBS object could also help.

Finally, 420 mb isn’t all that much - you could upgrade your hardware.

After the blocks have been exploded, I’ve found SelSmall to be a real time saver when I’ve received such files.
Depending on the file, it can be used to group similar objects (like fasteners) by size.