Huge jump in file size: 240MB to 10GB

Rhino Rhino for Mac
1

Hello,

I am working on a 3D model and plans of a warehouse with brick walls as infill walls between the steal structure. The bricks are all in blocks. In general, I have used blocks wherever possible.

I created _Make2D elevations from all wall segments (blocks with nested blocks) but unfortunately the Make2D lost/forgot/didn’t see many internal parts in the wall. The bricks where represented inside the brick-Block only as outlines, so the internal rods should have been visible to the Make2D command. As a workaround I had to explode all wall segment blocks. The created 2D curves where then copied to another file and deleted in the original file, as were the copied and exploded wall-segment-blocks.

Somehow, the original file has jumped from 240 MB to 10GB !!!

I tried all solutions I could find on the forum. I let ClaudeAi compare the Audit3dm for both files. Here’s what Claude has found. My SystemInfo is attached at the bottom.

I’ve tried the solutions suggested by Claude but to me it seems as if the exploded blocks and make2d curves are still somehow in the file although I have deleted them.

What could be the remedy here?

Key Differences at a Glance

240 MB file (V95) 10 GB file (V96)
Archive size 243,190,592 bytes 9,999,467,105 bytes
Object count 210,418 590,238
Plug-in data items 78,474 504,542
Object table size 221 MB 9,975 MB (~9.75 GB)
Properties section 318 bytes 2,892,159 bytes
Revision count 2,076 2,091
User data tables identical (18.4 MB) identical (18.4 MB)
History records 137 (identical) 137 (identical)

Root Cause: Massive Object & Plug-in Data Explosion

The overwhelming cause — ~9.75 GB of the 10 GB file — is the Object Table. Between V95 and V96:

  • The object count nearly tripled (210k → 590k objects, +379,820 objects)

  • Plug-in data items increased 6.4× (78k → 504k items)

  • Crucially, many objects in V96 are very large: you can see repeated objects of 739,039 bytes (~720 KB) and 527,232 bytes (~515 KB) each appearing multiple times in the list. These are almost certainly render meshes or high-resolution meshes baked onto geometry.

The 240 MB file has none of these outsized objects — its objects are all in the hundreds to low-thousands of bytes range.

Most Likely Culprits

1. Render meshes were saved (most likely) Between V95 and V96, someone likely ran a render, shading, or mesh operation that caused Rhino to bake high-density render meshes onto the geometry and save them into the file. The repeated ~720 KB and ~515 KB objects suggest complex mesh data attached to many instances of repeated geometry (e.g. blocks or array components).

2. Block instances exploded into individual objects The object count nearly tripling strongly suggests that block instances were exploded (Explode command) or that a block definition containing many sub-objects was modified, causing every instance to store its own full geometry instead of referencing a shared definition.

3. High mesh density / mesh refinement applied The _RefreshAllTextures, _Shade, or custom mesh settings could have caused Rhino to generate and cache very fine render meshes for all objects.

What Didn’t Change

  • All plug-in versions are identical

  • The history records are exactly the same (137, same structure)

  • User data tables are byte-for-byte identical (18.4 MB each)

  • No embedded images added

  • Same Rhino version, same machine

Recommended Fix

  1. Run _ClearAllMeshes in Rhino on the V96 file — this strips saved render meshes without losing geometry. If that slims the file dramatically, render meshes were the culprit.

  2. Check for exploded blocks — compare the block/instance table between the two versions. If V95 uses block references and V96 has them exploded, that’s a major source of bloat.

  3. Save with mesh settings — when saving, use SaveSmall (File → Save Small) which discards render meshes from the file.

  4. Properties section bloat — the Properties section grew from 318 bytes to 2.9 MB, suggesting thumbnail previews or metadata were embedded in V96 that weren’t in V95. Minor compared to the object table, but worth noting.

    System Info.txt (5.3 KB)

2

Hi Viktor,

Have you run _Purge on the model to get rid of unused elements?

Purge | Rhino 3-D modeling

HTH
Jeremy

3

Hi Jeremy,

I forgot to mention that I’ve also tried to Purge the file. I did both, Purge and ClearAllMeshes which brought down the file size to 5.5GB but still way too big.

Seemingly, the problem stems from the exploded blocks, which have been cut from the file and pasted into another, but somehow the data remains in the old file.

4

Hi Viktor,

It’s hard to know where to go with this without seeing the file. But as a possible workaround, have you considered selecting the stuff you do want and using export selected to put it in a new file?

Kind of like walking away from the problem instead of solving it, but possibly quicker. You’d want to be careful how you select stuff though (‘All’ potentially a bad idea!).

5

This is something common when you explode Blocks.

Let imagine you have a block that weight 1Mb and you replicated it 1.000 times.
The file size would probably increase to 1.5Mb because the block is stored in the memory and then displayed 1.000 times.

If you explode the block you get 1.000 time 1Mb = 1 GB of space.
Simple math.
If you can NOT Explode blocks, if you can’t… try to delete the blocks you don’t need before exploding it.

Hope this helps you.

6

Thank you Jeremy for the suggestions.

Since this is a client file, I cannot share it in the current state. I need to see if I can replace the geometry with some other geometry and show the file then, but that takes some time.

I also thought about copying the the geometry to a new file but the 98 layouts have prevented me from doing so. Can you also copy the layouts to a new file (without having copy and paste every one individually)

I will try to copy the “good” geometry to see what’s left in the old file and wether it’s visible at all.

@skysurfer:
Thanks for the suggestion, but you misunderstood what the problem is: Of course, when I explode the blocks, the geometry and file size increases. But it should not stay at this large file size when deleting the geometry, right?

//edit:

So, I’ve transfered all visible geometry to another file with Cut + Paste. The new file with all the (block) geometry is 150MB, while the old, purged again, file still remains at 5,5GB.

My guess is, that there might be a bug that when you cut and paste objects “out” of a file, somehow the data remains “invisible” but “heavy” in the old file… I need to test it with another file..

7

Yes, use Export Selected to create a new file with your geometry in it. Then open that file, open the Layouts panel and from there you can import all the layouts from the original file in one go.

8

I didn’t know that it was that easy. I will try it! Thank you!