Chuck Reverse Safety, Part One

It has long been a problem risking reverse with a threaded spindle nose, and so a plan was hatched to try and add a method of stabilizing/locking the chuck. This in order to either prevent loosening in reverse or at best, safeguard things such that chuck could not undo dangerously. Here we make a split collar out of Al to be an exact fit on a very limited spindle nose area behind the chuck backplate boss, such that when locked up, a "drive" pin threaded into a backplate could engage.
One earlier plan was based on an expanding arbor inside a chuck, with a draw bar - but this would limit material lengths and also require two arbors to cope with two different chucks.
Part Two is now available - • Chuck Reverse Safety, ...
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