Posted on **Building a Dust Collector Cabinet**

#1 posted 886 days ago |
Area of a circle (pipe) is Pi X®^2. So radius of a 4” pipe is 2” so: area = 3.14159 X 2 squared = 12.566 square inches Radius of 6” pipe is 3” so: area = 3.14159 X 3 squared = 28.27 square inches -- Michael :-{| “If you tell a big enough lie and tell it frequently enough, it will be believed.” ― A H |