[scoperoller]

The end mill holder will not unscrew. I have had this problem before; I actually sold a manual Sherline mill last year because I could not remove the end mill holder. I have used as much force on the rods as my hands can supply; I have put some oil down the interior of the spindle; I have tapped the bottom of the holder with a brass hammer (end mill removed of course); I have used a hammer on one of the rods to try and break it free. Do I have to replace the headstock? One of the reasons I have bought non-Sherline end mill holders is that they have a hex fitting allowing use of a wrench.

[awerby]

Try heat. A propane torch should do the trick. Play the flame all over the endmill holder for a couple of minutes, trying to keep it off the shaft. The expansion of the metal will allow it to unscrew, as long as there's a heat differential between the holder and the shaft.