Just thought I'd add a bit more information....I'm building (or attempting to build) a 3 frequency Geodesic dome. I don't have trouble with strut lengths, just getting the correct angles on all the pieces so I have a tight fit with all parts without the need to use hub connectors of some sort. My model will be approximately 5' in diameter, with 3 different strut sizes with the longest just a teensy bit over 12" and the shortest a bit over 10 3/4". If I were building this with condiut (or another similar material) I wouldn't need to worry about connecting angles, but with wood, it's very difficult to assemble the geodesic dome unless all the parts are miter-cut to precise angles. Unfortunately, that sort of math isn't in my areas of expertise, making it frustrating to keep hunting for the correct method of calculating these angles. And again, I don't want to go through the trouble or expense of purchasing hubs for the dome (if they can even be bought, of which I have serious doubts). I also feel the structure wouldn't be as structurally sound without tight fitting wood joints. I will be using reinforcing metal straps to reinforce the joints, but I refuse to use hub connections.
Again, any help would be appreciated, especially if it comes in the form of a nice drawing with the precise angles I need to cut detailed on each strut length.