Pimp My System: Geek Stir Plate
Let your geek flag fly! Daniel Schreffler, Pennsylvannia native, Wyoming Valley Homebrewers member, and AHA card-holder, took some old computer parts and set out to save some money on yeast by building his own stir plate. A few odds and ends, one wireless router, and $5 later, and Dan no longer worries about his starter while at work. So put your magic cloaks on, grab yourself a fermented elixir, and see what Dan has to say about the project:
Ensuring a proper pitch rate for your beer has been drilled into my head over the past few years. I've managed to do so by buying many smack packs or vials (you're welcome Wyeast/WhiteLabs!). But there comes a time when you need to make a starter—checking the viability of older packs, dealing when the local homebrew shop did not have enough of the yeast you need, or just being frugal.
Ok, yes, I'm the frugal one—ingrained in me by my grandparents who reminded me often, "Waste not, want not."
Building a good starter requires keeping the yeast in suspension—so in the past I had simply shaken up the mason jar every few hours. That's ok if you are home, and don't mind the occasional foam up and mess, but not so good when at work. I needed a stir plate, but did not want to buy one. So using that new fangled internet, I found a number of good documents on building your own stir plate using old computer parts.
As a computer geek, and borderline hoarder, there was enough old-tech parts around my house: CPU fan, hard drive for the magnets and a power supply. The challenge was what to use for a base. At first I considered the pure minimalist approach with just attaching the fan to a piece of Plexiglas. Then I saw the old router in the electronic junk pile. This would enhance both my brewing and geek "cred," even more than my homebrews named after D&D terms. "Roll For Initiative" was the first beer I made.
I pulled the router apart, removed any diodes/chips off the circuit board that were in the way, glued the fan on the board, and attached (just wrapped, did not even solder) the fan leads to the power adapter port inside the router. I should of taken a picture of that, but I forgot, and I'm not pulling it apart now. Trust me, it will be obvious, and you can use a voltmeter to confirm the right points of contact.
I cut out the top of the router, where the air vent is to allow clearance for the fan/magnet. I only had to buy a $5 stir bar—thanks Simply Homebrew, and sorry I did not buy that $80 stir plate.
A 1-liter Erlenmeyer flask sits nicely on top and the variable power supply allows me to throttle up with no issues. I have to try a 2-liter flask next, as I learned at the 2012 AHA National Homebrewers Conference from White Lab's Neva Parker (members can view/listen to Neva Parker's presentation here) that a 1-liter starter is really not worth the effort. That may mean I'll need to scavenge my e-piles for a bigger piece of old technology!