Boll Weevil Brewery

When I first built my immersion chiller, I was thrilled at the cooling performance it gave me, but as with all immersion chiller users I quickly discovered that the performance was greatly assisted by stirring the wort during the cooling process. I would hook up the hose to the immersion chiller, turn on the water and let'er rip. Watching the thermometer it was easy to see how stirring accelerated the chilling, so a pattern of remove the lid, stir, wait, remove the lid, stir, wait was all too familiar during the end of my brewing sessions. Being lazy, and I am lazy, using something to automatically stir the cooling wort was the next logical step. I had read on the internet about using ice cream freezers and other slow revolving motorized items, and decided to build one for myself.

The picture above is of the wort stirrer in place on a turkey cooker that I use for brewing. The pot actually belongs to a friend, but possession is 9/10 of the law, so I guess technically it's mine, heh heh. :-) The cutout is where my immersion chiller tubes enter/leave the pot.

As you can probably tell from the above picture, the wort stirrer is made from an electric ice cream freezer that I picked up from a local thrift shop for $2.00. (score!) I thought this was a great deal, and they had another one exactly like it for $5.00 or so, so you can find these things relatively cheap if you just dig a little bit. As you can see in the label to the left, this particular model is a Rival Model 8210, so if you use another brand or model there may be some differences in the way it's made, so this may mean that you have to modify the way you make yours. Hell, I kind of threw this one together from scrap parts anyway, so you'll probably want to modify things even if you use the exact same model, heh heh.

This is what it looks like with the ice cream freezer pretty much intact. The three bolts/nuts/washers you see on the base of it on the left are what I came up with on the fly for legs to make it stand off of my convex lid for the cooker and they were a pain in the butt to install so I didn't want to remove them just for a photo op, so in this picture just pretend they don't exist, ok? :-)

. I ended up using some scrap bolts that I had, but I'm sure there is a better way of doing this. I wanted it to be "non-slip" so that the motor wouldn't spin around on the lid if things got stuck, so I drilled 3 matching holes into the lid, and these 3 bolts stick down into the holes locking the motor in place with the washers and nuts acting as feet to hold the motors weight. Again, I'm sure there is a better more aesthetic way of doing this, but it works. Ok, let's see what pieces we can use from the ice cream freezer and what else we'll need to make this baby do our bidding...

We will need something to stir up the wort, so why not use the paddle that comes with the ice cream freezer? It stirs up the ice cream, so it should stir up the wort as well. As you can see in the picture, this is a separate piece from the top (gray) part, and it pulls off relatively easily.

We'll also need something for the other end, where out paddle assembly will attach to the motor. This piece shown to the left was already available, it was removable, and it was a perfect match to the gear pattern on the motor, so we'll just use it.

Next, we'll need a shaft to attach the paddle and the fitting above to. I'm sure there are tons of different things that could be used for this, including copper or stainless steel rods or tubing, but I happened to have some #4 bare copper ground wire laying around. It is relatively stiff over short distances, and like the copper immersion chiller it will be fine to boil for 15 minutes to sanitize it, so I'll be using that. Hard drawn copper tubing would also have worked, and would have been much easier to drill into for attaching the above parts. Your mileage may vary though... I measured this piece so that the paddle would be somewhere in the middle of the cooker, but I'll probably shorten it a bit so that the paddle is closer to the top of the wort. Putting it nearer the top should allow the sediment cone that the whirlpool creates to remain relatively undisturbed.

In this picture you can see where I drilled out the paddle so that the copper shaft would attach to it. I used a plastic drill bit sizing guide to determine the correct drill bit size for the copper rod then carefully drilled out the center of the plastic. I also drilled a smaller hole all the way through both the paddle and the copper shaft so that I could insert a small pin or screw (I ended up using a small stainless steel screw) to hold the shaft in place. Looking back, some JB Weld or high heat epoxy would have probably been easier to use rather than drilling through the copper rod, but I wasn't sure about the food-safe aspect of using it. I had a good assortment of very small drill bits, so I chose to drill it out.

I did basically the same thing on the motor end; I drilled out the center of the plastic piece using the same bit so that the shaft hole would be a tight fit, and then I drilled a smaller hole all the way through both pieces for a retaining pin. This end isn't in the wort, and it needs to be removable easily so that the paddle assembly can be separated from the lid, so in this case I used a high tech paper connection device that I modified (i.e., a bent paper clip). This doesn't look too pretty, but it works very well.

Here you can see the top part mounted into the boiling pot lid. I drilled a hole through the lid a couple of sizes bigger than the copper shaft just to give it some "wobble room" and then used a rubber faucet washer between the plastic part and the aluminum lid. The only weight on the washer is the paddle assembly itself, and the rotation speed isn't very fast, so a rubber washer works just fine.

Just pull out the paper clip, and the plastic piece and the washer slid off and the shaft and paddle can be removed from the other side. I leave this all connected during the boil to sanitize the paddle, but I tilt the whole lid over so that it doesn't cover the boiling wort.

This shows the complete assembly mounted into the lid. You can see two of the three feet holes where the motor sits. The motor fits down onto the little gray plastic part, but the weight of the motor is actually held on the legs rather than bearing down on the plastic.

This is the completed assembly upside down on top of the ice cream freezer motor.