Building a large carbon filter - anyone have the instructions from the old OG?

There was a step by step tutorial posted on the original OG that showed how to make a large carbon filter / carbon scrubber. It had duct reducers, duct clamps, flat pieces, chicken wire and pantyhose. Did anyone happen to save this tutorial, or perhaps have your own set of step by step instructions?

I made one and it worked great for many years. It was about 40 inches tall and had an 8 inch circumference. I’m pretty sure it would cost a lot more to buy a similar sized one, so I’m looking to make another if anyone can hook me up with the instructions.

Thanks!

Ps. I’ll post a tutorial if someone gives me the 411

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I believe this is the one you’re looking for here:

6th post down for the tutorial and if you scroll further theres copies of all the pics

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Great work, @ChronicMcBudz!!:clap: That’s definitely what I’m looking for! :+1: Thanks very much!

That was posted to mycotopia.net in 2006, which was a few years after I built mine, but I think those are the same pics and instructions. I wonder if that poster ripped the original post from OG that I followed?

Oh well - problem solved, and I’m very grateful for your help. As long as that link is live, I don’t see a reason for me to do another tutorial - we can all just refer back to your link.

Thanks again!

BTW - is there a site that houses all of our old OG posts and pictures?

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I actually want to say the original poster to OG reposted over there, but it’s been a long time and I could be mistaken. And unfortunately no, a lot of the growfaq and strain guide were salvaged, and you can find reposts of a lot of the most popular posts, but the majority went down with the servers.

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I have plans for one from OG. It’s a wooden cabinet on casters. I have that how-to if you want it.

I made quick n’ dirty one up ages ago with a 5 gallon pail and a hunk of 4" (2’ will do) round duct. Cut a hole in the lid for the duct to pass through and drill a whack of small holes to act as an exhaust, put a stocking over the end of the duct, extend it down to just above the bottom of the bucket. Surround the duct while filling the bucket with activated charcoal.



Leave the duct empty! You only want to surround it with the charcoal. Hook up a fan of some sort however you choose and you’re good to go.

*note - If I recall, I had my wife hold the duct in place while I poured the charcoal in. It was being a real pain in the patience trying to hold it in place with one hand while adding the charcoal on my own.

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Thanks @Schmokey - I would like to see your cabinet carbon scrubber. I’ve already purchased all the stuff I needed to build the one I was asking about, but I can return everything if I change my mind and decide to go with yours.

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@Purple-N-Hairy - I’ll see what I can do about uploading the article for you.

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@Purple-N-Hairy - Not ideal (should probably be elsewhere on the site), but this will serve the purpose.

(Shamelessly ripped from the OG OverGrow) Originally contributed by: GeeO

Building a carbon scrubber for de-odorizing stinky grows.

The design is such that there is no back pressure on the grow box exhaust fan, and there is maximum surface area for the exhaust air to contact the carbon.

The basic parts list:
2"x2"s and 1/4" plywood sheets, cut to the size of the furnace filters being used
4 furnace filters
4 to 5 lbs. of activated carbon
A set of four casters (wheels)
Duck tape, screws and four *hanger bolts 2" long by 1/4-20 with wingnuts and washers to fasten one removable side for filter servicing.
*Hanger bolts are machine threaded on one end and wood screw threads on the other end.

It starts with the frame construction:

In this example, the measurements of the box, furnace/fibre filters etc…
the scrubber is ~ 17" x 26" x 48" tall… the furnace filters are 16" x 25" x 1", though they are really only 3/4" thick. But again, your design dimensions will depend on the furnace filter size you choose based on the design criteria.

Wheels for mobility, and a wire screen on the bottom to hold the weight
of the de-odorizing filter without the filter buckling.
Using 4 furnace filters and 4 1/2 lbs. of activated carbon to make
a dual layer de-odorizing filter. 2 furnace filters on the bottom,
then a layer of carbon, another furnace filter, another layer of carbon,
and a furnace filter on top.

Carbon layer number one.

Carbon layer number two.

Tape up the carbon/screen layers, and then tape to the base,
creating a completely sealed bottom.

Add the walls and top.

Precut the input air opening before attaching the sides,
and add appropriate interface hardware.

Tape up the box seams with duct tape (the metal tape is best),
and it’s ready for action.

Design criteria and further comments
The design is solid and works well at eliminating that smell
as long as the following criteria is observed:
For every one (1) cubic feet of exhaust air to scrub:
Have a minimum of 1.25 ounces of activated carbon.
Have at least 8 square inches of filter surface area.

The concept has been tested for several months with multiple grows of the smelliest stuff available. not only does it work well during the grow, but the same technology has been used successfully in drying chambers to eliminate the odor of drying bud (sometimes far worse than the grow itself).

Ionizers are a waste of money to ganja growers. I did try the design with an ionizer inside the enclosure, no difference.
I have also used ozone and found it to be very effective in conjunction
with carbon for larger grows where the design criteria could not be met (too much air flow for the filters used), but the ozone is after the carbon and not before, since carbon absorbs ozone, and i want the carbon to saturate as much as possible with bud stink, then the ozone to clean up the rest.

The carbon is changed every three (3) months or so, and so far, it has not reached saturation within that time period.

Some Q & A about the carbon air scrubber

Why is the box so big?
To eliminate back pressure on the exhaust fan to maximize air movement through the grow box. I am sure the overall dimensions can be scaled down, though I am not sure to what dimensions.

Could u do this to a regular grow box?
Yes, although you want all of the workings in the top of the box. Exhaust fan, carbon filter, etc., venting out of the top of the enclosure.

Where did you purchase the carbon?
The neighborhood fish/aquarium store has the pricey stuff, at around $10+ per 2.25 lbs. It comes a lot cheaper, though you might have to change it out more often. Mail-order fish supply places over the net are the way to go when purchasing bulk activated carbon/charcoal.

*** I bought a huge (50lb+) bag of activated charcoal through my hydro supply store - Schmokey

Last modified: 06:26 - Nov 23, 2001

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@Purple-N-Hairy - You now have three different designs for carbon scrubbers in this thread, all OG designs. Good luck, and do let us know what you end up doing.

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Thanks for the info on both of those designs. Each is interesting and appealing, and considering your apparent experience with both, apparently also effective. The cabinet style looks large enough to place the inline fan inside of it, which would be helpful for controlling the noise it makes.

As it turns out, I have almost everything at home I would need for your cabinet style carbon scrubber. The only thing I’m missing is the filters (I use permanent/washable filters for my home HVAC). I even have the casters for some strange reason. So I will seriously consider this design before I make my final decision.

Thanks again for sharing!

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To be honest, up until now I haven’t had the need for a larger cabinet style scrubber and found the 5 gallon pail design to serve my needs. I had gutted an Honeywell multi-speed room air cleaner for the fan and used flexible duct to make it all work.

Now that it’s legal to grow here in Canuckistan I’m rebuilding my entire setup (a proper grow room) and I’ll probably build a cabinet scrubber (of some sort) myself. As effective as it has been, that 5 gallon pail is heavy, awkward to move around, and a bit of pain to maintain without help.

These 3 designs you have put together give a pretty sound basis for how to put together a carbon scrubber. How you get it done is just a matter of doing whatever works for your needs.

A couple things to keep in mind - if you want to use ozone to “sweeten” the air, keep your ozone injection AFTER the carbon scrubber. Likewise, if you are running CO2 enrichment, only use your scrubber to treat air you are exhausting from your grow. The scrubber will absorb CO2, removing what would otherwise be available to your plants.

As for the sharing, don’t mention it. That’s why we’re all here!

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