circle

[kubotaman]

I know this has been discussed before but I can't find the thread. What is the easiest way to find the diameter of a circle when you know how long a chord is and also the rise?? thanks!!!!!

[jdervin]

Assuming the rise to be measured perpendicular at the midpoint of the chord:

Diameter = H + (W^2 / 4H)

Where:
H = Height of the rise
W = Width of the chord

Follow this link for more info...
http://www.mathopenref.com/arcradius.html

[kubotaman]

Thanks John. I found it a little earlier. Thanks again!!!

[bleeth]

This little spreadsheet was posted on Woodweb years ago:
It work perfect for a variety of things including arcs:

http://www.woodweb.com/knowledge_base/_Spreadsheet_Calculation_Program.html

[gc3]

http://search.barnesandnoble.com/Circular-Work-in-Carpentry-and-Joinery/George-Collings/e/9780941936484

link to a excellent reference book

[kubotaman]

Thanks guy's for more information. I got a equation yesterday but of course I figured it wrong but was able to find out what I did wrong. At least now with the spreadsheet the computer will do the wrong calculation!! That is a really handy spreadsheet! Thanks again!!