Jacobs Taper 3 Machining

[pzzamakr1980]

I just purchased a Tormach tooling system to use with my Sieg. I got everything I want with one little problem. I have a high quality keyless drill chuck with a JT3 mount. The problem is that Tormach doesnt sell a JT3 adaptor for use with their system. I believe I could make one since I purchased a great deal of tooling to go with my new lathe but I dont know the taper angle or how to figure it out. According to the wikipedia the small end is .7461 inches in diameter and the large end is .8110. The overall length is 1.2188. I know with this info you should be able to algebraically figure the angle out but I don't remember how. Anybody remember?

[Crashmaster]

Well, I am in the process of making one and you just let me know the dimensions
I needed. Dont quote me on this, but I believe the angle is 1.5251. I will let you
know for sure in a few hours after I make it and test it.

[Crashmaster]

Using those measurements you listed with a 1.5251 angle, sucker fit perfectly. I machined it using a CNC lathe so I was able to hold a .001 tolerance though. Good Luck.