This tip will save you a huge amount of money

Prepare 2 additional nets and coconut fibers;
Place them between the 2 networks and close them with zip ties;
Drill another circular hole just in front of the vent mechanism;
Install the mesh you just made and fix it with screws;
Place a tube along the edge of the mesh;
Place one of the 2 parts of the tube on the motor;
Make the electrical connections by preparing an ignition system and a plug to connect to the power. Don’t hesitate to call a competent person if you are unable to do so;
Attach the cut-out top to close your DIY fan;
Plug it in and try it.