A while back I released a spreadsheet to do some math for things that might crop up during model and part editing. I recently unearthed it and converted it to a Google Sheet. While there are online calculators out there for most of this stuff, I like having one stop shoppoing. Note that this a is work is progress so there may be errors and other things wrong. Hope someone finds this useful.
https://docs.google.com/spreadsheets/d/1...sp=sharing
https://docs.google.com/spreadsheets/d/1...sp=sharing