Classic cars forum & vehicle restoration.

[buzzy bee]

Hi

Remotely to do with Transport, as I am making it as a part for a tractor!

I need to make a Frustum of a cone, I have the top circumference (a) and bottom circumference (b), but to make it I need to draw it onto a piece of plate before rolling. I also have the required hight. But:

How do I find the circumefrfence of the two large circles that the parts a and b are a section of?

Hope you understand what I am on about, I just can't work it out, it has baffled me all night! There must be a formula for it, and I need to make it tomorrow. If I can't work it out, I will have to do it differently, the long way round, also I won't be able to impress everyone at work!

Cheers

Dave

[Greeney in France]

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[Greeney in France]

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