TheBitterBrewer.com

After reading through responses to my post on NB forum on "How much is too much yeast?" : http://forum.northernbrewer.com/viewtop ... =1&t=70145 I decided to harvest only a small sample of yeast from my yeast cakes from now on and make a starter using a stir plate.

The photos below show the build process. The entire project could have cost less than $10, but I "splurged" on a project box for $5.99 from Radio Shack.

After this complete I tested it using a paper clip.

OK, two updates. First, the 1" aluminum spacers may have been too far from the surface. So I replaced them with grommets I had laying around (they're probably about 1/4 inch. Second, the 9 volt power supply I was using spun the fan way too fast for the stir bar. I replaced the 9 volt supply with a 5 volt dc supply that I had laying around from a Motorola RAZR phone.

I put everything back together and tested with the flask and stir bar that arrived today from Northern Brewer.

I'm a complete moron when it comes to stuff like wiring a thing like this. It looks like I have the same rocker switch and pot as you're using, so can you give me a run down of what wires go to what please?

TIA,
Scott

Hi Scott, hope this helps:
Step 1: Connect the positive wire (red) from the power supply directly to the fan’s positive (red) wire
Step 2: Connect the negative wire (black) from the power supply to the middle terminal on the rocker switch
Step 3: Using a small wire (about 4 inches), connect one of the outer terminals on the rocker switch to the middle terminal on the potentiometer
Step 4: Connect the fan’s negative wire (black) to one of the outer terminals on the potentiometer switch
Step 5: Make yeast and drink beer.

that's one of the most comprehensive write-ups I've seen Twitt! Nice work!

For those of you that don't feel like flagging down all the parts or want the improved performance of a voltage regulator driven stir plate I finally released this kit:


It runs $14.95 plus shipping and includes almost everything you need but a fan, drive magnet, case and stir bar.

After some minor tweaks to the magnet placement on my fan (thanks to this article: http://www.madzymurgists.org/stirplate.cfm and the photo below) I was able to place the magnet in such a way that it doesn't cause the stir bar to wobble at all. I was then able to upgrade my power supply to a 9v and get great results. I can get my 1000ml flask to vortex straight to the bottom. Will post video soon...

Updated video: