08-23-2013, 06:00 PM
This is a perfect example of the dramas associated with mass production of heat treated components.
There is a simple explanation as to why the threads are pretty much always sloppy on these hardened steel collet chucks.
The reason is that as the threads are cut prior to hardening they need to be cut oversize, then the register faces and bores are ground after hardening.
As a result if the spigot is accidentally ground oversize, then the irregular thread always pushes the chuck to one side taking up all the clearance resulting in an offset of twice the clearance.
There you go, text book combination of production errors resulting in a part failing to meet specification, the upside is understanding these errors better means we can avoid them
There is a simple explanation as to why the threads are pretty much always sloppy on these hardened steel collet chucks.
The reason is that as the threads are cut prior to hardening they need to be cut oversize, then the register faces and bores are ground after hardening.
As a result if the spigot is accidentally ground oversize, then the irregular thread always pushes the chuck to one side taking up all the clearance resulting in an offset of twice the clearance.
There you go, text book combination of production errors resulting in a part failing to meet specification, the upside is understanding these errors better means we can avoid them
Whatever it is, do it today, Tomorrow may not be an option and regret outlasts fatigue.