Harold and Susan Vordos wrote:

I regularly run my Bridgeport @ 4200 RPM with that setup. No problem.
Even with the tool extended somewhat.

Most of my flycutters are el cheapo crap I bought 15 years ago. None of
the larger ones can run at that rpm without vibration from being out of
balance. Always intended to do something about that, and just did, by
replacing them!

Jon