What is the taper

[kd4gij]

Doesn't match anything that I can find on the web. It is about .035 per inch taper. Only markings is H1 and P&W

 

[NCjeeper]

Maybe P&W is Pratt & Whitney so maybe google them and see it they have some proprietary tapers?

 

[Martin W]

Are you sure it’s not a Morse taper?
Martin

 

[MrWhoopee]

Looks like some B&S taper endmills I was given. They look very close to MT2. I turned them straight and shortened them.

 

[benmychree]

End mills are commonly Brown & Sharpe taper. Morse taper does not hold well with side thrust, and even B&S sometimes can work loose.

 

[Illinoyance]

.035 x 12 = .420 taper per foot. B & S is .500 per ft. Morse is about .625 per foot. Ether you measured wrong or you have a really bastard taper.

 

[benmychree]

As I remember, all the B&S tapers are slightly different in taper than each other, the result of lack of fine measurements when they were made. One of them, #9 or 10 was not even close, as the result of a mistake and it had to be initialized because the machines had already been sent out.

 

[kd4gij]

I am sure it is Pratt & Whitney as it has Hartford under the P&W. Is doesn't match anything Morse, Brown & Sharp, or Jarno. As found in these charts. I found a manual for a Pratt & Whitney mill that used a B&S #9 with a drawbar in the spindle. It must be a custom taper for either a tail stock on a P&W lathe or a screw machine. It is a 1 inch 2 flute endmill or a counterbore

Dimensions of Standard Tapers

This page give the dimensions of Morse, Jacobs, Brown & Sharpe, and Jarno tapers.

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