[modeleng] Releasing chuck taper

Gentlemen
   
  Yesterday, I thought that I would try to make a simple (!) drilling jig, by 
drilling some holes accurately in a piece of 6mm thick mild steel that I had 
machined in the ML10 to fifteen-sixteenths of an inch square.  The next step 
would be to hold that piece of steel in the nippy vice on the old, very old, 
Dore Westbury mk.1, but before I could do that, I had to remove the Clarkson 
type milling chuck so that I could install the drill chuck that is normally 
installed on the tail-stock of the lathe.  The fun is about to start.
   
  The Clarkson type milling chuck, a Vertex, is on a Morse Taper No.2, and has 
a tapped hole in the end, 3/8" Whitworth for a drawbar.  As the bore through 
the spindle of the DW is smaller than 3/8", I had to make a drawbar from 5/16" 
ms, plus an adaptor (5/16" - 3/8").  I had removed the milling chcuk from the 
DW once before, and it had needed some persuasion.  Even more persuasion was 
needed this time.  I tried hitting the top of the drawbar (protected with a 
piece of wood) with a small hammer, then I tried a bigger hammer, then i tried 
hitting the drawbar directly with the hammer, only to damage the thread on the 
end of the drawbar.  After re-cutting the thread with a 5/16" die, I put extra 
nuts on the top of the draw bar, and belted these with the heavier hammer.  The 
morse taper would still not shift.  Finally, I took the drawbar out and 
squirted WD40 around the top of the milling chuck and down the bore of the 
spindle.  After leaving the WD40 to penetrate for five
 minutes, I put the drawbar back in, gave it a tap, and the chuck morse taper 
released quite easily.
   
  Is there an easier way to remove a stubborn morse taper?
   
  Jem Harrison
  battling with basics in Basildon, Essex, UK !

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