Hi Robert, imperial units are currently not supported. However, diametral pitch is reported in the gear data, e.g. in reporting. We may add support for imperial units in the future as we also implement more standards that use them, e.g. AGMA.
After many months of no activity on my part, I just started playing with your program today as I just found how to get to the actual program. Also, just converted a gear I was playing with to metric, however I am still not getting the "module" converted properly from Dp in English. (Help!) Also any chance you could restart or extend the free trial as I am just now getting my feet wet and encouraged so far. Also I did see the DP in the data section so worked backwards in iteration.
Bob, I think you will find the equations here useful:
It appears your current trial is still active. Feel free to contact me when your trial ends if you still have questions.
Can units be changed to imperial?