Intro: Automated All Grain Homebrewing System
Use computer controllers to automate the brewing process
Combine our mash tun and boil kettle into one container
Use motors to automate grain immersion and removal
Have a stirring mechanism built in during mashing
Include a chiller for quick cooling and moving into fermenter
Step 1: Brewing Process and Objective
The main two processes we are focusing on are mashing and boiling. Mashing is when you take malted crushed grain and immersing it in warm water to convert the starches to sugars. The important part of mashing is to maintain the heated grain and water around 153˚f for about an hour. Different recipes can call for different times and temperatures. The next part to brewing beer is the boiling phase. Before we bring the mash up to a boil we need remove the grain. Leaving the grain in during the boil will add unwanted flavors in your beer. Once the mash is brought up to a boil we add our hops in. Usually boiling lasts around an hour with different times of adding the hops in. After these two processes we will cool the beer down and put it into a fermenter where the yeast is added and the beer is sealed up and let sit for a couple of weeks.
Step 2: Parts
Kettle – Any stainless steel kettle can come with a valve on
already. We made our kettle out of stainless steel sheet metal. Our kettle is around 20 gallons. Remember that you will have however large batch you want to do plus the space that the grain takes up. This would probably be a pretty good one.
Support arm – We built the support arm with 2 inch diameter and around 64 inches tall stainless steel with a 2 x 2 square stainless steel beam that is about 24 inches long welded on top of the pole.
Stand – We build the stand using sheet metal and 4, 1 inch diameter, stainless steel poles as the legs.
Wheels – We used caster wheels to make it easier to move the system around. These are similar
Tubing = running between the pump and kettle – needs to be rated to withstand boiling temperatures. Silicone is usually a good choice. Make it same size to fit your valves.
Spud for Heating Element
Pump – make sure it can withstand boiling temps
Transformer for pump
14-3 Wire - might look for something different
40 A SSR x6
Electrical Box similar to
Wire 22 gauge – we used black, multiple colors would be helpful something like this would have been great!
Hoist - We got our hoist from harbor freight but here is the link to the same one
Step 3: Tools
We used a Makita polishing wheel to smooth and clean all the surfaces of the kettle.
Makita angle grinder was used to cut any of the different pipes.
Soldering Iron – used to make the circuit board.
Tig welding – used for all of our welds
Drill Press – used to drill multiple holes in the kettle
Always use the correct protective gear. Face shield and safety glasses for angle grinding. Also a face mask with a filter while grinding/polishing any metal.
Step 4: Fabrication
Drilling on drill press
The first thing we did after building our pot was drilling all of the holes we needed. This included a hole for the heating element spud 1” diameter about 2 inches from the bottom of the pot, one for our drain we used a 1” bit again 2 inches from the bottom 90 degrees from the main drain. We then drilled a hole for the temperature probe directly across from the heating element. For the 2 valves for the pump we put them on either side of the heating element leaving a little space between them and the heating element.
We made our own basket out of stainless steel mesh and some pieces of pipe. We cleaned up all of the holes with the polishing wheel. We then welded on all of the valves and spud. For the “out” valve for the pump we put it at an angle to help us get the liquid moving in a circle around the pot. We then welded our supporting arm together. We used a 2 inch diameter pole that was around 72 inches tall to a 2x2 square bar that we used to mount our lift to. Next we welded together the stand. This included a piece of sheet metal with a small lip just large enough for our pot to sit inside it. With three 1” diameter poles that were around 24 inches tall as the legs. We then welded the legs of the stand to the bottom sheet metal stand. On the top of the bottom plate we welded a 24 inch tall pole with an inside diameter of 2” for the support arm to sit in. On the bottom of the bottom support plate we welded on 4 caster wheels to make it so we could move the system around. We made our own basket usinga 400 micron 316 stainless steel mesh. In order to keep it together we ran rings around it vice gripped it and welded the rings together along with the stainless mesh. The seam of the stainless mesh was held together by soldering. Across the top of the basket we ran a thin piece of stainless steel with a hook that we could use to pick up the basket.
Drilling holes into electrical box
We drilled two large holes around ½” diameter into the box one on each side. One was for the power coming in and the other we used to run our wire from the computer to the Arduino. We also had to drill holes for each of the SSR’s and the arduino to mount to the back of the box. We did this by laying out everything where we wanted it to go and marking each hole location. We then found a couple different nuts and bolts that we were going to use and made the holes large enough for them to slide through. We then mounted all of the SSR’s and the Arduino/Circuit board.
We removed any burrs and polished all surfaces that would have any welds. Since we made our pot using a 16 inch pipe and some sheet metal we polished the whole kettle, inside and outside, this might not be necessary if you purchased a kettle that is already clean.
For the temperature sensor a 4.7kohm resistor has to go between the 5v (red) and the data (yellow) wire. We soldered the 4.7kohm resistor into the board across the red and yellow wires. We ran all of our wires from the Arduino to the circuit board mostly just to keep them from coming out of the Arduino so often. Refer to the schematic to wire the Arduino to the 6 SSRs and the temperature probes. We combined the wires from the SSRs for the hoist together so that they would send the signal to both of them at the same time. These were both mounted to a small wood piece which could then be attached to the electrical box.
The lift came with 2 brackets and bolts that easily attached over the support arm.
The plate chiller easily screws onto the drain valve.
Step 5: Wiring/Electrical
To control the hoist we have to use 2 sets of 2 SSRs. When 2 of them go high it will allow the hoist to go up and then when the other 2 go high it will make the hoist go down. Refer to the drawing to see how to control the hoist. I found a lot of good information about controlling the hoist at https://www.instructables.com/id/How-to-hack-an-Electric-Hoist-AC-motor/ . The hoist comes with a large capacitor. We put a 200k ohm resistor across the capacitor and used electrical tape to secure it. We also ran the power from the wall through an SSR and connected it to the heating element (5). We connected power from the SSR to the heating element and the negative to the negative from the wall. We also ran power from the wall through another SSR (6). From that SSR we went through a transformer to drop the 120V from the wall down to 12 for the pump. From the transformer to the pump. Refer to the drawing for how to wire the project. Watch out for that capacitor it can give you a nasty shock. We mounted all of this in our electrical box that is below the kettle to allow for easy access to all of our electrical components.
Step 6: Code
The Arduino code uses a lot of Boolean variables. This helps keep program only running specific loops during the brew based on what phase of the process you are in. The only parts that should change in the code are the MashTemp, BoilTemp, BoilTime, and MashTime. Attached is the code. We use a computer to power the Arduino and also use it to track the process using the serial read function in the Arduino coding.
Step 7: Conclusion
I'll be adding some more pictures the next time I get it out to brew. Make sure to always use the correct PPE. Be careful when working with electrical.
You can see a more formal write up here https://drc.libraries.uc.edu/bitstream/handle/2374...