I was looking for a project that combined my three favorite things - working in my shop, building cool stuff for my bar and of course, drinking beer. After a couple of weeks in the old country drinking "the Guinness", I decided my I'd put a keg of "Moothers' milk" in my kegerator and prolong my vacation until the next visit...which led me down this path.

Despite conventional wisdom, the Guinness is usually NOT served warm on the Emerald Isle -  there were few places I drank in that relied on "cellar" temp to cool their beer. According to the Guinness Storehouse, the Guinnness should be served at 8° C (46°F), which means it needs to be colder than that in the kegerator, as the laws of thermodynamics definitely apply to beer kegs. A guy in Donegal (where they serve the finest pints!) told me he keeps his kegs at 3°C (37.4°F), figuring by the time the pour ends it'll be close to factory specs. 

Usually we keep fine homebrewed kegs of ales, pale ales, barley wines and stouts on tap at the Check 6, but lately the Guinness has become de rigeuer. The problem is, I never really paid that much attention to the temp of my kegerator. My beer always seemed cold enough and no one ever complained, but when I stuck an old school fridge themometer in there recently, I was shocked at how warm it was :-)

So why build this? Fridge thermometers work just fine but you have to open the kegerator every time you want to check the temp. And every time you open the door it screws up the controlled thermal environment. Using this little guy allows you to track inside temps which will help you find the proper setting for your kegerator thermostat.

Enter the Arduino + DS18B20...

Step 1: Find a Project Box

Any old project box could do, but not at the Check 6 Saloon - we need something a little more elegant. v1.0 was hacked out from a hunk of Eastern Cedar, which has some nice character but didn't match the dark woods in the Check 6 Saloon. A few days ago my partner (no, not that kinda partner) and I went over to his Grandad's house to pick up some walnut that had fallen and been roughly boarded. Absolutely beautiful stuff to work! After several runs through the table saw, planer, chop saw, router and mill, we came up with project box v2.0, which is roughly 4"x 3.5". This oughtta fit the guts nicely.
Awesome! Another good site I found for great prices on parts to make stuff is BGMicro.com
Nope, your Bacon Fat Cookies recipe beats this by a mile :-) I'm making them next weekend!
You're a good man! Combining Arduino and Beer! It don't get better than that! Thanks for posting.

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Bio: Just a guy who likes to build cool stuff...
More by spikec: Ammo Can Speaker Insanity: The MOAB *duino Keg Temp Monitor, or the Quest for the Perfect Pint Arduino-powered A-10 stick grip remote w/Emergency Party Button!
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