Originally Posted by
tri4sale
that's how they taught it in the 2 day class at ShopBot I took, basically don't over tighten, that all you really need to do is the one hand squeeze.
I took that same class and got misled. When they said "Don't over tighten" I think they meant Arnold Schwarzenegger type folks. I ruined some wood and one spoil board over that idea. Sure, don't kill it but the collet nut needs something like 77 ft/lbs. of torque to be set correctly (ER25). That's more than a gentle squeeze. For the average non-body builder type, the one hand squeeze should be about maximum effort. Less than optimum and the end mill may migrate out of the collet and cause very unattractive gouges in the work and spoil board. It can also kill the collet.
At the Aspire camp a few months ago, the advice was "The average person cannot over torque the collet."
ShopBot Details:
2013 PRS 96x60x12 (Centroid upgrade)
4hp Spindle
12" indexer
Aspire
Rhino
Fusion 360
Ferrari 360
Prusa MK3S+
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