Duplicator 4X Fan_Duct_ mod

This is actually a modification of an exelent design, found on a page by SmartBlug.
Since it lifts the fan out of the box, it's possible to use a 60mm fan.
A 40mm fan typically delivers 12m3/h, while a 60mm fan gives you more than 30m3/h.
(Thats in open air whithout back pressure, but the difference makes it worth a try.)

NOTE: There is a modified and improved version of this thing!
You find it as "Vertical_Fan_Duct_Wanhao4S"