How do u cut a 90 or 45 degree cut in HVAC duct?

Question

How do u cut a 90 or 45 degree cut in HVAC duct?

Answer 1

I am assuming that you don't need rectangular ducts as that is easy.  For round ducts, the intersecting shape for same size pipes is a sinusoid (one cycle) with the height the same as the diameter for the 90 degrees, while the 45 degrees is half the height.  There are also CAD programs that allow you to design any HVAC pipes.  See http://www.cadpipe.com/hvac.html?gclid=C...