Fan is supposed to be shrouded. When I put it on it was set exactly to text. Blades in a 1/2" -1/2" out . I can put a paper in front and it will suck it right to the grill . I read a good read by Spall . They claim all electrical fans will loose as much as 700 cfm when in use that means my 2250 cfm fan is only making 1550 , not even enough to keep it cool in the shop.
