Internal taper question

Assuming a taper length of 2", the major - minor diameter is 1.940" - 1.874" = .066". Half that is .033. That divided by 2" is .0165 which is the taper in in/in. This is also the sine of the half angle and the arcsin .0165 = .945º. If the taper length is 1.5", then the taper would be .022 "/" and the half angle would be 1.261º.
EDIT: Actually, it would be the tangent, not the sine. but the angle would still be .9453º for the 2" length and 1.2603º for the 15" length.

In SolidWorks, here is the solution.
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You must have a math or engineering degree. I am always amazed with your math knowledge. I just have basic HS math so I am always challenged in this area.
 
You must have a math or engineering degree. I am always amazed with your math knowledge. I just have basic HS math so I am always challenged in this area.
Yes, I do have a math degree amongst others but I learned the trigonometry in 3rd year high school math sixty years ago.

I can appreciate that you find dealing with the math difficult. I added the SolidWorks drawing for that reason. With a parametric CAD program like SolidWorks, you sketch out the part, add the dimensions you know, and the CAD program does the hard math for you. It took less time to make th sketch than it did to run through the math calculations. While SolidWorks isn't economically feasible for most, there are other CAD programs available for little or no cost. They require a bit of effort to become adept enough to use them, but IMO, it is time well spent.
 
Pethagoream's Theorum ...................Siney of the Hiney = the Angle of the Dangle . ( from what I remember)

I made about 30 of these sine bars for the apprentices as a project years ago . Pretty easy to set compounds to exact angles .
 

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Tom Lipton, OxTools, did several videos on setting up angles on the compound using a sine bar and on measuring internal tapers using a double ended gage.
 
This has been a great discussion, thank you. The cat got skinned in another way that my head could comprehend. The gap from the base of the flange was 3/32 over 1.5", I angled the compound, set the start gap at 3/32, then marked the bar at 1.5". When I got the start to finish exactly at 3/32 to 1.5" my angle was set, and it worked, thank God. I guess where there is a will there is a way, even a dull knife in the drawer will still cut, and I'm not the sharpest. Thanks again for all of the support.
 
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