Yeast Stir Plate

One item I've been planning on building for a while is a yeast stir plate. The purpose of the yeast stir plate is to boost the cell count in yeast starters resulting in higher pitch rates and healthier starters. This should reduce lag time before active fermentation begins and theoretically should improve the final product.

Commercial yeast stir plates can be fairly expensive so I'm going the DIY route. I wish I could claim I came up with the idea for the stir plate, but it's basically modeled after others on the web. The components and prices are as follows.

Disclaimer: I'm not an electrician and I can't guaranty the safety of this device. If you choose to build a similar device, do so at your own risk.

• (1) 80mm PC case fan - $2.49, Electronic Goldmine



• (2) Rare earth magnets - $2.00, Electronic Goldmine



• (1) 8x6x3 Project box - $6.99, Radio Shack



• (1) 25K Ohm 3 watt rheostat - $3.99, Radio Shack



• (1) Knob - $1.99, Radio Shack



• (1) Power supply - free



• (1) Switch - free



• Miscellaneous screws, zip ties, etc. - free



• Stir bar - approx $5 (yet to be purchased)

Here is a very basic wiring diagram that even non-technical people should be able to understand.

Click here for Steps 1-2