Wanhao Duplicator i3 extruder fan housing and ducting 60mm fan adaption.

housing ducting to fit 60mm fan with circular (toroidal) air duct.

60mm fan gives plenty of cooling.
also the length of the body has been increased 5mm and shifted to give better clearance around the extruder (for my printer at least).
there are two sets of mount holes for optional position.
Printed in two parts and glued.
can be printed as one, but better finish in two parts.

three files:
main body,
60mm adapter
whole piece

adapted from design by : BliNDF123