The Fermentation Chamber Update

The construction phase…  I started with the base frame of 2x4’s on 1/2” plywood with casters.  At this stage it doesn’t look very imposing at 4 feet wide and 3 feet deep.  Filled with R13 insulation and covered with 5mm fascia board.  From there I added part of the back with two 6 inch holes for the squirrel-cage fan motors.  The holes are lined with stovepipe duct to prevent the motors from sucking in insulation and burning up.  The picture are right shows the wall at 48 inches high where the compressor motor will sit so that this area can be reinforced.  It will be continued later to the full 72 inches.  Some trial and error in this area caused me to have to use a hand saw to remove the center of the top 2x4 and replace it with a 2x6 to fit the depth of the compressor.

The side walls go up in much the same fashion with 2x4 frame secured with drywall screws, the inside fascia board installed, the insulation cut and inserted and finally the outer fascia board.  The frames were pre-built at the same time and then fastened to the base with 4 inch deck screws before using a pneumatic stapler to secure the fascia board.  This 5mm plywood from China isn’t exactly structural material, but it is fairly easy to work with and although lacks some of the depth and warms of true hardwoods or birch, it doesn’t look bad.

This next image requires some explanation.  This is what the inside of the chamber looks like without the front on it.  Two 5 gallon water bottles are shown sitting in the bottom to give some perspective on the scale.  The compressor “hump” can be seen 2/3rds the way up the back wall with the chiller plate fastened to the top with a machine screw and a spacer.  The air is handled by the two squirrel-cage fans and using 2x3 plastic downspout for rain gutters.  Very inexpensive and because the air never travels outside the box, I only used friction fit to secure the downspout.  If a little air leaks at the joints it isn’t big deal.  I designed the air movement to pull from the bottom and push to the top assuming that the cold air will fall if nothing moves it around.  The concept is to have one fan on all the time and the other turn on when the compressor kicks on. 

The 2x4 box sitting on three 2x4 legs is a mock-up of a 14 gallon Blichmann Fermenator, which I plan to purchase next year.  The rails fastened to the side walls are supports for the shelf.  The chamber is designed to accommodate a 14 gallon Fermenator, two 6.5 gallon carboys on the bottom and four, 5 gallon carboys or Corney kegs on the top shelf.  I also wanted to be able to put cases of bottled beer on the top shelf.  The bottom being for fermenting and top being for controlled temperature ageing. 

The shelf, shown at left is constructed of 2x4 pine ripped to 1.5x1.5 square lengths with 1.5x1.5x1.5 square spacers to allow for airflow from top to bottom.  I wanted to make sure that  I didn’t have to worry about putting 200lbs or more of fermented liquid on it and not having a catastrophe.  The shelf weighs over 20lbs once finished with spar varnish.  The entire inside of the cabinet is finished with spar varnish to prevent moisture from wreaking havoc on the wood.  Almost a gallon of varnish was used in the construction of the cabinet.  Notice the space left at the front of the shelf, this is for the front which at the time of this picture had not even been designed yet.  This was as far as I got with the “on paper” design phase of this project.  Wait till you see what happens next…