Hello,

SETUP: My question is about calculating the length of a cable wrapped around an elongated cylinder fig. (A). I’ve found on-line calculators that will give me that data for a coil around a cylinder fig. (B). http://deepfriedneon.com/tesla_f_calchelix.html however I don’t know if that’s the same surface area as fig. (C).

I did a physical test with a string around a can (D). Made a mark on the can and wrapped the string around two times and cut the string at the same mark were the string started. Then squeezed the can to shape an oval fig. (E). Then rewrapped the same string around the squashed can. The string started and stopped at the same place as on the round can. I guess no surprise that the surface area didn’t change.

MY QUESTION: But squashing the can fig. (E) and the shape (A) seem to be two different surface areas. How can I calculate the surface area of (C)?

GOAL: My ideal would be to make a calculator that I could change the shape profile and get the wrapping calculation as in http://deepfriedneon.com/tesla_f_calchelix.html

RELATED QUESTIONS: 1.) Is there a geometric name for fig. A or C?

Thanks for and help in this matter.

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