The idea is very simple: You just need something to support the filter, and obviously, something to filter.
For supporting the filter I used some kind of metallic fence; the only thing is to adjust it to the shape of the cabin air intake. I bought it in a hardware store for 2€ a meter (I couldn't buy less than one). Here some photos of the metallic support:


And finally, here we have the filter. Is some kind of kitchen smoke extractor filter I also bought in the hardware store; It cost about 4€ and the filter was about 1.5 square meters of material. I use two layers to increase the effect; I've tried with three layers and it also works fine, without any noticeable power loss.


Is not the greatest DIY project, but I think is very cheap, useful and easy to build. Thanks for reading; if you want more photos or details, just ask


