Luk---

Thank you :) The funny part is that it's not easy to get the reflex to use it even if it is next to you. you often forgot that you have a drink in it. It's quite useful when the table is very crowded.

It is 3mm plywood. Maybe 5mm wood be sturdier, but this 3mm plywood looks nicer.

hello, I already tried. It didn't worked and made strange noise and bad smell...

Thank you. I realy need to study electronics...

I corrected it. Thank you.

around 250€, a bit more maybe. a little more than 100€ for the fan, 60€ for the filter, around 20€ of wood, around 20€ for the electric gears, 20 to 30 for different other things. I had other ideas, too complex so I spent more than that but the model itself should not be more than 250€, probably less.

If I read correctly, PM2.5 are particles that are smaller than 2.5µm. H7 filters are stopping 98% of 3µm ir bigger particles. It's not very efficient for smaller particles (only 25% of 0.1µm particles are stopped).A thiner filter would be necessary, E12 or better I guess. I'm not an expert.

I answered than on a another topic : I don't know electronics and very few about electricity.

It's very loud. The fan constructor is announcing 70db. I strongly recommend to chose a variable fan. I clearly made a mistake on this.

I'm using the laser cutting machine from a fablab so it's not intended for commercial use. I'm also in France, so it could cost you some money just for sending it. There is some online commercial services that might help. I know (but didn't test) https://www.sculpteo.com/en/ I'm pretty sure there is other companies alike. If you choose this solution, you may print on paper and cut it by hand first to be sure that you pieces are adjusting correctly.

I have very limited knoledge in electricity and none in electronics (I've just searched PWM). I guess the fan has an induction motor. It was featured with a control device (the black thing in the electrical box). Maybe it is controllable by PWM but it's far from my skills for now. Thank you for your concern.

I bought it on ebay from a british company : http://www.ebay.fr/itm/Centrifugal-industrial-extractor-fan-blower-1700-RPM-600-m3-h-230-V-/322237641871?hash=item4b06dc348f:g:YRQAAMXQNo5TWpqE

The rules are in the wikipedia article in the link in the begining of the text.Here's a video about how to play : https://www.youtube.com/watch?v=G90o0ai57EM

Thank you everyone for your comments and advices.

thanks for your comments.

thanks everyone/merci