I’ve always struggled with chattering. It’s always been good enough but I never got a truly smooth surface. Then I stumbled across spiral flute countersinks that: a. Promise a perfect surface and b. Promise to empty my wallet.
https://www.mcmaster.com/countersink...ks-for-screws/
https://www.guhring.com/BrowseProduc...s/Countersinks
thoughts?