

I’ve seen this before and I still don’t entirely buy it. If you’re talking about the pattern left by the nozzle rubbing the print, that will not be a reliable identifier.
Most nozzles are brass. Soft metal. It wears down and the pattern in the plastic will change. Because they wear down anybody doing regular prints is gonna replace their nozzle from time to time. New pattern in the plastic.
This is assuming they don’t change a new $2 brass nozzle, print a gun part, then toss the nozzle in the trash. Or the whole printer. My printer right now is probably $150 used at this point, if I was to sell it.
Imo this isn’t gonna do much, and for the people who would do nefarious things it will be easily avoided.
(This is ignoring changing print settings, nozzle diameter, filament type, print temp, etc)
I think my issue is practicality in testing. They have to have the print, and the printer. To test they likely need the file, modified with the same slicer settings as set originally. There are just so many factors, I have a hard time seeing them get all the required pieces, get them all in working order (especially the printer), then have the means to print the same thing in the same way. After all of that, now they have to measure some patterns and prove they’re the same across prints.
I feel like the complexity of the problem introduces more chances for false positives, or just enough of a shift in how the printer is tuned, how the file is set up, etc to make the process unreliable at best.
I guess we’ll see, but idk. A poor tool still has potential for abuse even if it doesn’t work as originally intended.