This post is interesting.

https://www.askmehelpdesk.com/engine...le-128919.html

I'm going to re-state it as a math problem.

Suppose you have an 8" x n * 2 * PI piece of paper. This paper would wrap around the circumferance of a piece of pipe. Now suppose the pipe is cut at theta degrees. Now draw the cut at theta degrees on the piece of paper.

What is the equation of the curve on the flat piece of paper that would wrap around the cylinder of n diameter that would create the cylinder cut at an angle of theta? How might you draw it

The point of reference is your choice.

Solve it for a 6" diameter pipe and a 45 deg angle.