The best way to test things that spin is to increase the RMPs until it explodes.
The people at AXT Turbo in Dandenong Victoria. Australia do a lot of testing so they decided to test the the durability of a fidget spinner.
“At work AXT Turbo, we have to test a lot of our turbos. We were playing around with the fidget spinner after work, seeing how fast and what the structural integrity of the unit is. We first started with finger on it until it got a little hot. Then we put in in a vice. After it let go, we calculated it was turning 50000 plus RPM.”