Ok my first attempt at a simple carbon filter failed miserably....It just didn't have enough surface area to be effective and stacking more active carbon just slowed the volume of air to an unacceptable level. I was sitting around last night and decided that I already had all the materials I needed, just need some pantyhose from the old lady...A nice pink pair at that!
I cut the flange end off the 4" vent elbow I already had and wrapped the 1/4" mesh wire around it and secured it with self tapping screws. I taped the seam to keep the sharp edges from tearing the nylon stockings.
I then made a second cage slightly bigger than the first, again taping the ends and the seams to protect the stockings.
I then installed the nylon stockings on the inside cage, starting at the end opposite the flange.
The next step was to slide the outside cage over the inside...again from the end opposite the flange.
The nylong stockings were then stretched over the outer cage and pulled down to the end opposite the flange. The created a pocket in the nylons between the inner and outer cage.
With the flange resting on the table, I filled the cavity between the two cages with active carbon, you can see in one of the pictures where it is partially filled.
Once I completely filled the gap, I pulled the end of the nylons over the fill area and then taped the whole thing completely closed.
It is working great! Now my plants aren't that smelly yet so we will see down the road how effective it remains!
It completely removed the mj plant smell and there is no noticable reduction in air volume....
Oh yea, it is about 12" long and 4" diameter.....