replying to chris, Elden wrote:
Chris,
I realize that you posted your response more than 2 years ago, but I would
like to ask you a question. Did the chuck you used grip the spindle well or
did it ever slip during heavy use?
The drill press I have calls for the JT#2 1/2 as well. It has worn to the
point that one has difficulty getting it tight enough with the chuck key to
prevent slippage on the drill bit.
I used an online calculator for finding taper angles
(http://www.magafor.com/841/uk.htm) to compare the two Jacob Tapers. Using the
specifications for the JT #2 1/2 and for the JT #6 that I found, they were
plugged into the calculator. The values obtained we JT #2 1/2 2.82°
cone angle or 4.929% taper; JT#6 2.97° cone angle or 5.191% taper. The
differences were 0.15° for the cone angle and 0.262% taper.
I realize that the differences are small, but they are the reason for my
initial question. I would like to know from someone who has actually put it to
a prolonged test whether it is a workable solution.

Thank you for your time,
Elden

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