i3 Mega FAN Covers for Noctua 40x40 fans

After finding some nice 40x40 fans from Noctua, for hotend cooling and stepper cooling, I tried to find fitting covers. The ones I found were mostly producing a lot of extra noise. As the fans themselves are *verrrry* quiet, I thought that would be a pitty. So fired-up CAD and designed some that fit the airflow-philosophy of Noctua.

I left the original metal cover in place, just made some big holes in there to have optimum airflow. Now there is hardly any difference with or without the cover