Hi, this is a simple mod. The basic idea is to use aquarium areator instead of fan to cooling printed pieces. This config have some advantage .. Extrude and Bed temp more stable and power consumed is some less. My max power consumed is around 80w.

The STL file you find on download page  
The external diameter of tube is 5mm, internal 4mm.  I flattened one of the ends.

On video below the expletation ..

Areator Mod, Fan on/off

Hi, this is a simple mod, it consist in insert relè into areator.

The fan on reprap system is controlled with 12V PWM signal. The relè it is not possible to direct connect to PWM signal, it is necessary to adapt the signal.

 

For this signal adapter, you can procure  two  component:

- 1 bridge diode

- 1 condenser of 16V 100microF

The bridge-diode have function of decoupling from PWM signal. The condenser have function of stabilize PWM signal.

obviously another component that you will need to have is the relè. You find a relè that have voltage around 10~15V, the best is 10~12V.

This circuit accept various signal to activate relè like these: 12V PWM, 12V AC, 12V DC

The scheme is very simple, see below ... but ..

Be very careful because you do not mess with 220V