File keeps making four empty named layers when re-opened

Dear people!

I have a file with a lot of layers in it. Using blocks and regular objects/curves. Yesterday I noticed that my file is getting 4 layers which I don’t need/want;

*- New
– Layer 02

  • Standards
    – M-Thread_Base_Curves*

I can delete the layers, but if I save the file, and reopen it, the layers mysteriously have returned. I can not figure out where they came from, and why they keep reappearing.

Hope someone here knows the cause.



Just a couple of shots in the dark - are any of the blocks referencing an external file? Or, on looking at the layer names, they look like they might be created by a plug-in like BoltGenerator…?


Hey Mitch,

It might have been Blocks that are containing other blocks, but i’ve just removed those cases, yet no change in behaviour of the file.

The names are all hand named, we created the bolts ourselves with custom made curves. So it’s model related not caused by any plugins as far as I can tell.

Assuming they áre coming from a block, how would I be able to derive what block layers are coming from, when the layers don’t have objects in them to trace back.

I don’t know really… If you run BlockManager, does say if the file has any hidden or reference block definitions?

It did before, but not anymore, I’ve edited all the blocks (as far as I could see) that had blocks nested in them.

The block manager is now ‘clean’ but the layers still return to my file if I open it.

I’ve now been trough a part of the blocks manually and found a block that contained said layers. So the assumed cause was correct, but i’m wondering if Rhino supports any options to backtrack a layer’s origins.

So in my case:

  1. A layer comes into the main file from a block
  2. I did not notice what block it came from
  3. Does the unwanted layer contain any information on what block is it’s origin?

OK, if you said

A layer comes into the main file from a block

so the blocks you are referring to are externally referenced files…? Any time you import files the files’ layers are imported with them, even empty ones. I don’t think there’s much hope in this case, as I don’t believe layers have a memory as to where they came from…


Yes I could at least in the file find no reference of where the layers originated from. I did manage to find them by manually opening around 80 (out of 300+) blocks, checking them for the layers. I’m glad I was able to find them so ‘quick’.