I can't believe I waited this long to build one of these things. I followed the 'Son of Fermentation Chamber' plans you can find online, unmodified. Given the effort to build one, I built two of them from the start, probably should have built a third right away.
I just fermented a hefe @ 60 with no problems (house was ~75-85) and there's a strong red ale (Gordon Clone) in one now. My brewing friend has a Mead in the other one.
- I got 2" polystyrene (a nice blue) from a local roofing place. The stuff is messy as can be, but machines great with a skill saw, table saw and hole saws.
- Everything was glued together with liquid nails, and then all the seams were sealed up with silicone caulk. The ice chambers can actually hold ~10" deep of water when I tested it without leaking.
- I glued some corner round molding on, again with liquid nails for the front/top to push against.
- To get a good seal with the doors I laid down ~3/16" bead of silicone on all the surfaces (against the front/top) -- waited 30 minutes -- and then squished it flat with the front/top and weighted it. This made a great silicone seal on all the edges. I did the front/top separately and left it a few hours to harden.
- Home Depot carries RiteTemp 6022 thermostats. They go down to 35 degrees. A friend de-soldered the thermistor and relocated it on a 4' length of lightweight extension cord. This way we can mount the thermostat on the outside and plunk the thermistor into a thermowell.
- The 6022 thermostat has a hold feature so you can plunk in a temp and just stay there. If you're really into a temp ramp, you can setup the 7 day program to slowly ramp the temp.
- Radio shack sells male/female plugs for power. You can wire these up to an existing 12v adapter and off the chamber to make it easy to plug in the power supply.
- Finally, I traced the fan a couple inches down from the top of the chambers and used a hole saw and hacksaw blade to cut out a perfect hole the fan just slides into.
Best thing I've added to my brew collection yet and it has amazing temperature control. Each one cost ~$50.
pics in next post.