We used to do similar BS back in metal shop in School . 3D-printed was not invented yet, but lacking that newfound Tech. we still figured out how to fuck with the other people running machines. My favorite was to take a piece of crappy soft pig iron square rod stock . Then using the precision magnetic grinding plane, making it into a nice 'Fake' right or a left hand Lathe cutting Tool . The just leave it laying around for any student to see, pick-up and proceed to use his new found 'Free' tool cutting on their 'to be graded on' project . .. was Fun Times.If anyone actually does this they need to be kicked so hard in the balls that their testicles become their ear lobes.
Seeing as we have both 3D printers and mills, I now know what must be done. What I need to do is bang on the back of the mill at the same time this breaks.
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