Need help in editing a .mdl file

[Matrix7689]

So, I made a prop in hammer using Propper software and converted the brushes into a .mdl basically.

But now I want to edit the .mdl file (delete/add brushes) because I made a few mistakes in it and I also lost the original item made out of brushes...

So is there a way to decompile it or I am just screwed for life?

[Squad]

You can decompile a model using Crowbar, but the decompiled file can not be opened in Hammer (the file format is for 3DSMax and maybe other packages too).

I think in your case, given that you lost the original vmf, there's not much to do except to rebuild the whole thing in Hammer, I'm afraid.