In article DpqAh.3666$Aa5.2325@trnddc01,
Joe AutoDrill wrote:

Make sure to open the chuck all the way in either case so that the jaws are
retracted. You don't want to damage the chuck jaws at all.

Shoot me a private e-mail (anyone) and I'll email you a PDF with the basics
for a Jacobs taper...
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R



Joe,

Some years ago Jacobs had chuck repair procedures on their website.
Their instructions for a plain-bearing chuck (not bottom-end
multicraft, not sure about the ball bearing chucks) were that the
jaws be opened to approximately the half way point and that the _jaws_
rather than the sleeve be pressed or struck. The reasons being that the
jaws are high strength hardened steel, much stronger than the sleeve
and more importantly, the sleeve is simply press fit onto the chuck.
If it is struck or used as the surface to press on, it is quite possible
and even likely that it will move further back towards the end of the
chuck with the taper. If it does move, the chuck key will no longer fit.
If you disassemble one of these chucks for cleaning or repair it's
easy to see how this can happen.







--
There is always an easy solution to every human problem -- neat,
plausible, and wrong." (Mencken)

Larry Wasserman - Baltimore Maryland - lwasserm(a)sdf.lonestar.org