Taper Turning between centers

Tinkertoy1941

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This post is for discussion about turning tapers between centers with the dead center in the spindle and the live center OFFSET in the tail stock.
The material to be turned 12L14 with centers made in the lathe chuck with a center drill
The shaft to be tapered being driven with a lathe dog
What are the thoughts on the effects of the male centers being at different angle than the shafts centers affecting concentrically?
Or taking the part out of the lathe to check mating fit with a known tapered sleeve and being able to replace the part on centers exactly from the previous cut?
 
I have been thinking about making a tail stock center with a small ball on the end just because of that. The ball rides inside the center.
 
I believe the angle is limited (not sure what the maximum is, the tailstock is one limiting factor) but yes you can remove and replace the part.
Mark
 
The core is a "bell center drill"; instead of the 60 degree angle, the bell center drill has a curved cutting edge roughly bell shaped; that being said, I have no idea if they are still available, I have only ever see/owned one. I doubt that a small offset such as a Morse taper or similar taper would have much effect on center wear or part geometry.
 
They are still available. Last time I looked Jack Hoying had three for sale.
 
The core is a "bell center drill"; instead of the 60 degree angle, the bell center drill has a curved cutting edge roughly bell shaped; that being said, I have no idea if they are still available, I have only ever see/owned one. I doubt that a small offset such as a Morse taper or similar taper would have much effect on center wear or part geometry.

Yup, still available.

http://www.shars.com/15-hss-bell-type-center-drill-combined-drill-countersink

https://www.amazon.com/KEO-18-Combined-Drill-Countersink/dp/B0034KY7PM

https://www.richardsmicrotool.com/product/802-0018/
 
Also a ball end mill would be a good choice me thinks.
 
I think that Jimsehr has the right idea!
My thoughts were to use balls that I have center drilled on the ends of both centers.

Center drill a ball the appropriate size for the center drill in the shaft a drop of Super Glue when setting up should solve any tolerance error.
When done a warm light to soften the glue a little cleanup and ready for the next time
 
benmychree said:
The core is a "bell center drill"; instead of the 60 degree angle, the bell center drill has a curved cutting edge roughly bell shaped; that being said, I have no idea if they are still available, I have only ever see/owned one. I doubt that a small offset such as a Morse taper or similar taper would have much effect on center wear or part geometry.

We always called this type of center "Protected Center Drill"
The 60 degree edge was protected from being damaged by the shoulder left when the center drill was drilled about an 1/8" deep from the end of the shaft
 
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