[quote=“CNCInspiration, post:22, topic:15797, full:true”]
I recently destroyed the threads on one of my er20 spindles, most likely either due to too many tightenings or probably just cranking it down too tight. Would like to stop doing it wrong lol.[/quote]
Don’t you mean collet nuts, like shown here?
This kit includes a 22mm wrench (which should fit the motor shaft). But who knows what’s safe and appropriate - maybe @Vince.Fab?