[BackPorchChoppers]

Poster board and duct tape. Make a templet first. Once you get what your looking for take the poster.board tank apart and trace the panels out on your metal. This will give you your braking points. As for degree you will be able to get that from your ma h up. Trust me it is the best way that way you can be positive of the style prism you are wanting.

 

[BackPorchChoppers]

You can use cardboard if you choose. I prefer to use poster board I think it works better and gives sharper lines on the templet.