Gear and Timing Pulley Design Resources
I was wondering if any of the more experienced folks out there knew of a good online resource that explains gear and timing pulley design.
In the past Ed Sparks had a good spreadsheet on his website that detailed the various dimensions of a sprocket. I'm looking for a similar resource for gears and for timing pulleys.
...I've been trying to make a timing pulley in Inventor, working with specifications from F.N. Sheppard, and I can get it close, but it never turns out right. For 1/2" pitch belt and a 2.81" outer diameter, I end up expecting 17.655 pitches -- and the specifications call for 18.