Quote Originally Posted by WashougalWonder
If folks have positive info, we could turn this into a good thread about how to calculate and make a DIY, as those out there are similar, but getting the right size is important to not cause other issues. There are few, all similar, but only the one I quoted from has info about calculating proper size.
I love this fan stuff. I spent a ton of time researching the ins and outs of calculating fan needs. However, for the carbon filter I never considered DIY, in part due to need to get sizing right and in part due to the mess and hassle of DIY. And I DIY most of my home improvement needs. For this discussion it is important to note that the carbon that you use is important; good carbon is a must.

Note that you should not mess with carbon unless you have a well ventilated work space and a GOOD dust mask - not one of those quickie $1.50 masks but a proper, fine particulate respirator (plan to spend $50 on the mask). You do not want this stuff anywhere near your lungs. If it goes in it ain't coming back out...

I do understand the urge/need to DIY one of these. A good, long lasting scrubber is not cheap by any stretch.