homemade fume hood

I have created the fan case, as you can see in this picture i had also separated parts of it to make it fit in the bed of my printer. I had struggled for about 30 minutes (which I had not logged even though I did take a lapse of it because I don’t think that time really counts) trying to find software to model the airflow of the fan but I was unable to find any software that was simple, free, and working on windows. I do hope the fan case works and it is able to be assembled. I am not able to print these parts at the moment because my 3d printer is currently printing an unrelated project for my mother.

I am creating a homemade fume hood so that I can do soldering with less worry of having negative effects in the future on my health, currently I have made the fan model, which attaches to motors I have, but have not simulated air flow which I will do later. I still need to make the frame and the housing for this. (btw this fan is a large fan like one you would find in an air purifier or dehumidifier for your basement)