a= the edge length
The circumference RADIUS is found by Rc= a / 4 * The Square Root of (58 + 18 * The Square Root of 5)
(I had to change the Square Root sign to text because the forum just couldn't understand the Ascii character.....
So if you want a diameter of 60" set your Rc equal to 30 so....
30= a / 4 * The Square Root of (58 + 18 * The Square Root of 5)
30= a /4 * 9.912074636
30=((9.912074636 * a) / 4
120=9.912074636 *a
12.106446370386269153593165094888 = a
so your side length should be 12.106 inches.
To simplify the process, multiply the desired RADIUS by 4 and then divide by 9.9121 .
I just KNEW my love of algebra and geometry would pay off eventually!
![Laughing :lol:](./images/smilies/icon_lol.gif)
Or just use this online calculator to find all the other fun specifications like surface area, volume, and mid-sphere radius.
Truncated Icosahedron Calculator