File size explosion - Rhino 6

I was adding some chamfers to an object in a file less than 500mb. After 10 or 12 chamfers, the file was still under 500mb. I added a few more (identical in nature to the others) then noticed the file had balooned to 3,131mb and slowed to a crawl. I checked for duplicates and none found. I exited and saved - the file shows as 3,131mb in Explorer. I reopened and Saved Small and the file went down to 3,060mb.

This is crazy… Any thoughts?


Yes, it is crazy, but I don’t think you’ve provided enough detail for anyone to have any additional thoughts. Can you repeat it? How about with the saved small file? How about posting your system info results?

I went back to the mother model and re exported the solid object to Rhino v5 file type. It is 87mb and after doing most of the 70 required edges to be chamfered the model is 87,818kb. Exporting fresh to Rhino v6 file type gives me a starting file size of 87,956kb with no chamfers. The bad file is currently 3,060,371kb after most chamfering and save small.

Same computer for all operations. A few reboots along the way to clear things up. I am currently completing the project in Rhino v5.


Hi Robb - Can you please export some of the chamfered (later ones, where the file blew up) to a new file and send it to us? And can you please run SystemInfo in V6 and post the results?


These chamfered edges are all part of one solid object. How shall I handle that? Not sure what happes if I explode and rejoin just parts of the object for export.That file is currently >3gb in size.

Hmm- for now, can you post the results from Rhino’s SystemInfo and, if it does not take all day, can you also post the results from Audit3dmFile for this file?


Here are the files Pascal. Thanks for your help with this.Audit.txt (6.3 KB)
RhinoV6SystemInfo.txt (2.4 KB)

Hi Robb - thanks… no answers yet but it appears your object is made of anti-matter, as the file size in the Audit output is vast but negative… I am making inquiries.

@rcmcdougle - can you zip and upload both pre and post chamfer models to

to my attention? There is a plausible theory here involving the ability (in V6) to edit previously made chamfers… but it would be great if we can see this happen here.




Could you have changed your meshing settings?
If you saved before and after files as small saves (with new filenames) how do the files compare?

Did you do a check for duplicated objects?

Can you handle a 7z file? It is about 300mb smaller than the standard zip.

Hi Robb - I think that should work, thanks.
@rcmcdougle - if you have trouble uploading the mega file, which you might, just send the unchamfered one for now - if we can see the thing bloat starting from scratch that will be enough to go on.

Yep, I see a failed upload… sorry - can you please try again with only the smaller file? Thanks…


On the way now. I see in the upload page that .7z is supported. Even so, the file is 756mb. I’ll be fascinated to hear what you learn.

As far as I can see so far, the extra file size is related to the ‘editability’ of the chamfers. By extracting a surface and re-joining, orExplode/Join, you can make the object a new one with no chamfer history and cut the file size back to normal - at least that worked here and supports the edit theory - a developer will be able to confirm or deny…


is there a way to purge that editability without explode and join? just to avoid playing with the edge tolerance.

Hi Diego - Explode/Join should not mess with edge tolerances as long as nothing is done in between. (shout if you have an example that shoots that down…) But ExtractSrf one face and then select that face and join it back to the part will also work.


not now but I had some situations like, for example, I have an open polysurface, explode and join and later it shows as closed and vice-versa. It surely because bad or messed modeling but I don’t know haha.
I’ve also read some post here about how exploding and rejoin modify some sort of boundaries on each surface, I will look for it.

Hi Diego - Join, or more especially, JoinEdge can force edges out of tolerance, but once joined, Exploding and Joining should not, I think, change anything - ugly edges will stay just as ugly and nice ones nice. Once joined the edges are pulled to some location and they do not move back to how they were on Explode - that is why Join/Undo is not the same as Join/Explode starting from clean edged surfaces…


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