120,000 RPM spindle - video

[metric_taper]

When things get up those high RPMs I have no use for them.
I don't know what is going on in the nearly 3 minute video showing a wobbly spindle spinning

Comments at the youtube page, asked this as well, one was funny to me:

silv425 9 years ago
It was machining air, which, let's face it, is a pretty easy medium to work on. The problems start when trying to check that the results meet the required specifications, both dimensionally and the surface finish.
I think that we were not able to see the finished part because some dork opened a window and it blew away. };-)