Taper Turning between centers

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
Yes, the type illustrated on the sites listed above are not the true BELL type where the whole form that replaces the 60 degree form is curved, not the double angled type illustrated.
 
benmychree said:


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

Exactly, a straight 60 Deg. V with in a counterbore to protect it.

The angles will have little effect unless the taper is great, people have been doing it that way for well over 100 years.

The modern method of turning a taper is to program it (-:
I now run CNC lathes mostly and rarely ever adjust the tail stock, just take a skim cut and measure it then program any taper out, this is a thing of sheer beauty that I never had for 25 years. Once you use a CNC lathe you will never ever want to run a manual again.
 
CNC is great!! But I still get a kick out of making details on my foot powered Barnes equipment.
Don't even have to go to the gym.
But as you say CNC makes it easy and the machinist of today will never know the pride of building things the old way before DRO and counting revolutions!!
 
A Toolmakers Ball would work nicely I believe.
 
But as you say CNC makes it easy and the machinist of today will never know the pride of building things the old way before DRO and counting revolutions!!

Not exactly correct, it does not make it easy merely less tedious.
You may yourself set up a manual lathe/mill operation that virtually anyone can run once configured, you have chosen the work holding methods, the order of operations, the tools, the feeds and speeds, set the stops and adjusted the actual cutting dimensions for the machine used. All that the operator has to do is crank the handles and handle the parts. A CNC or automatic machine does not require an operator.

Think of it as a manual machine that does the laborious handle cranking for you, it will not make the parts itself.
 
Check this YouTube out. Sounds like a good option.

 
CNC is great!! But I still get a kick out of making details on my foot powered Barnes equipment.
Don't even have to go to the gym.
But as you say CNC makes it easy and the machinist of today will never know the pride of building things the old way before DRO and counting revolutions!!

Some different skill sets are required, but those of us who started fully manual, then evolved into DRO users, then added CNC to their abilities know that it's no easier, if you are responsible for maintenance of your own machines and the full cycle from CAD designer through CAM processor to CNC Operator.
It's those who see only the "Operator" bit and haven't learned full 3D CAD/CAM that think CNC makes things easy :D
 
I recently purchased a offset center tool. I wanted to have a MT based die holder. I used this offset center tool, but I had to use a boring bar to clear it to turn the taper. Check out the video


Sent from my iPhone using Tapatalk
 
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