Active coal filter holder for 120mm computer fan

3D printers melt plastic and it doesn´t smell so nice. To tacle this problem I have always had active coal filter by the printer. After moving the printer to a new place it was time to make a better filter holder.

This one is a big one with a big area for the filter material. I use a active coal sheet made for over the oven fans. A sheet costs a couple of € and lasts for years. Thickness is 7 mm.

In the bottom of the holder is a standard 120mm computer fan which is drawing air in through t