Blocklayer
Member
You can use your iPhone as a hand tool to set a bevel gauge from the calculated rafter cut angle results and diagrams from this roof calculator.
http://blocklayer.mobi/roofeng.aspx
Heres a demo video http://blocklayer.mobi/Video-Roof.aspx
http://blocklayer.mobi/roofeng.aspx
Heres a demo video http://blocklayer.mobi/Video-Roof.aspx