The Auto Brewer is a life saver for the home Brewer who just doesn't have the time they used to have.  You love to brew but you have small children? Or just can't seem to find the time because of work or other life changes? This is the solution.  It's not a short cut, it's a time saver that drastically cuts down on your active time brewing.  It can be used for all grain or extract, your still boiling, and your still adding hops and other additions just as you would if you were standing next to your kettle, but you don't need to be there.  The AutoBrewer takes care of as much of the brewing process as you want. 

With the auto Brewer your day is broken up into three 15-30 minute blocks of time, which for me is usually further broken down between 2 days.  

1. Collect water, add metabisulfite and other water additions and weigh out hops and put them in bags in the freezer. Like so many Brewers I usually do this the day before and set it to be hot when I plan to brew the next day. 

2. Manually mash in, set up the fermcap injector, fill my hop scoops and plug in my hoist controller.  Press some buttons on my phone and walk away for about 6 hours on average.  (If you are not incorporating a relay controlled hoist or you are using a mash method other than BIAB you will have to manually mash out as well.  The hoist simply lifts the bag, and is simply a "no squeeze BIAB method")

3. Transfer and clean up. We have not figured out how to automate the cleaning process yet! 

This means the auto Brewer still takes about 6 hours to make wort, but my active time brewing on brew day is only 30-60 minutes! 

THE AutoBrewer has three parts.

1. The hoist or gantry crane has been a part of my brewery long before the AutoBrewer was a thought.  I have always used it for transfers, and for picking up and moving heavy objects like full kettle and fermenters.  The hoist is wired to 2 relays so the Arduino can tell it to lift the bag to end your mash.

2. The main base, where the Arduino, fermcap injector and scoop arms are mounted so that they can make additions during the boil 

3. The glycol chiller. We chill the boil with our glycol chiller, as well as using it for the usual fermentation process.  

Since building the first AutoBrewer we have simplified the build process to make it much easier for the average DIY Brewer with just a few tools.

We have reduced the wiring aspect down to just powering the Arduino and wiring relays by using an "Arduino nano relay shield module" with 8 pre wired relays. 

We have replaced the relatively complicated scoop arm with a simple, cheap T hinge.  The release mechanism was changed from having to precisely bend wire with a push pull solenoid, to using door lock solenoid.

The AutoBrewer build

1. The base

For the base we used a piece of 4'x4' by 3/4"thick  plywood, but any sturdy and flat material that is big enough should work, as long as you can screw things to it.  

First, we will make all our cut marks on the base (Fig 1.1)

Mark a line 12" from two sides so the lines are perpendicular to each other.  This will create 4 squares on your base, 3x3, 1x1, 1x3 and 1x3.

In the 3x3 square, draw an X to find the center, this is the center of your kettle. Using a string or other tool Mark your kettle diameter in the center of this 3x3 section.

You will make 4 cuts so that you end up with the base shown in Fig 1.2

First cut 12" off one side, then cut out your kettle diameter and finally make 2 cuts and remove a section as shown in Fig 1.2 so the base has a "keyhole" shape.

Hopefully you have something already the right height to place the base on otherwise you will have to put legs on it or otherwise support it over your kettle.  We use an old table saw table that's just right for us.

2. The scoop arms

Now it's time to make the scoop arms for your additions, this is the assembly that holds and drops your hops and other additions. With the Arduino nano and 8 relay shield module you have some options depending on your end goals.  If you are planning to incorporate the relay controlled hoist to automate your mash, 3 of your relays are needed for the hoist and the fermcap injector, detailed later in this section to prevent boil overs.  The 5 remaining relays can be used for your scoop arms.  

If you don't plan to incorporate the hoist, and plan to manually mash out, and manually add fermcap, you can use all 8 relays for scoop arms.

First, find enough large scoops that will hold enough hops for the largest addition you will need to do.  cut the handles off the scoops and sand away the excess material.  Measure the total length of your scoop and cut a 1"x2" to that length.  Using 1/2 inch screws attach the scoop to the 1"x2"

Next, using 1/2" screws attach the long arm of a 2" T hinge to the scoop arm.

Cut a 2"x4" 4" long for reach scoop and attach as shown in (Fig 2.1)

Arrange all the scoops as shown in (Fig 2.2) and screw down using 2" screws

Repeat for all scoops.

If you hinge is getting stuck it may just be rubbing on the wood, notch the wood out so it doesn't touch the moving part of the hinge. (Fig 2.3)

Solenoid position

Mounting the solenoid

We used 1/4" rod couplings to stand off the solenoid from the 2x4 base and mounted the locking ring low on the scoop arm.  Very little holding power is needed to hold the arms in place so leverage shouldn't be an issue.  (Fig 2.4)

First, start by attaching the locking ring to the solenoid.  Hold the scoop arm vertical in the position it will be in when loaded, place the solenoid flat on the 2x4 base with the locking ring plate against the arm.  Ensure everything is strait and in line.  Using your 2" screws, screw them down into the 2x4 through the solenoid mounting holes to mark where the solenoid will be mounted. See (Fig 2.5)

Using the 1/4 rod couplings and 2" screws, Mount the solenoid in the marked locations. See (Fig 2.6)

Raise the arm and position the locking ring base, while locked into the solenoid, on the arm so that everything lines up, Mark the mounting holes and attach the base using 1/2" or 3/4" screws. See (Fig 2.7)

Test, press the manual release to ensure the scoop falls as intended, and lift to make sure it locks in place. 

3. Fermcap injector

The final part of the physical build before we start wiring is the fermcap injector.  This is an important piece to prevent boil overs when your not going to be present for the brew day.  However, if your planning not to use the relay controlled hoist, and plan to manually complete your mash, you can skip this section and add fermcap yourself.

The injector is basically a 1/4" bolt that is spring or rubber band loaded. 

You will need a 3 to 5ml syringe, your scrap plywood, scrap 1"x2", 4" long 1/4" bolt, springs or rubber bands, and a door lock solenoid.

Any syringe that has about a 1/2 inch or less of travel for 1ml should work fine.  For example, the small yellow syringes that come with childrens medicine. See (Fig 3.2)

Injector cut list

1. 3/4 - plywood 3" wide 12" long

2. 3/4 - plywood 3" wide, your syringe + (see beow) long

3. 3/4 - plywood 3" wide 3" long, cut to fit solenoid

4. 1x2 - 3" long, 1/4 hole drilled on flat side, 1" high to center

5. 3/4 - plywood three pieces 1" wide 2" long

6. 2"x4" - cut at 45° angle see (Fig )

Putting the pieces together

#1 on the cut list is the base for the injector where everything will be attached 

The length of #2 depends on how your pressing the plunger.  If your using a spring on a bolt like we did, place the spring on the bolt and the syringe up against the bolt head.  Measure the total length from the end of the syringe (empty with plunger pressed fully in), to the end of the spring, this is the length of cut 2.

If your using rubber bands the measurement is just the syringe pulled to 1ml + 1/4" for the bolt head.

Using 1 1/4" screws, line up cut 2 on one end of the base and screw together.

Drill 2 pilot holes in the 1x2 and screw down with 2"screws as shown in (Fig 3.2, 3.3, 3.4) the 1/4 hole should be above the 3/4 plywood you just attached.

Insert the 1/4" bolt and spring into the hole, put the syringe in place and attach the two 1" x 2" x 3/4  plywood pieces as shown to hold it.

Test: pull the syringe plunger to 1ml.  Pull back your bolt and spring, place the syringe and let it go to ensure the syringe plunger is fully pressed

Find the center of the 3rd 1" wide 2" long plywood piece.  Using a 1/2" drill bit make a counter sink hole so a 1/4" nut will be flush with the face.  Then drill 1/4" hole in the center.  Attach this to the end of the 1/4" bolt. (Fig 3.6)

Using a miter saw cut the base at a 45° angle as seen in (Fig 3.5)

Attach your solenoid locking ring. (Fig 3.7)

Cut the 3"x3" plywood as shown to not interfere with the locking ring. Attach the solenoid to the 3" x 3" plywood as shown, lock the ring into the solenoid, pull the solenoid back so that the spring is fully compressed and mark the base where the 3"x3" should be attached.

Remove the solenoid, screw down the solenoid base and then reattach the solenoid.

Test: pull back the locking ring and ensure it locks into the solenoid securely.  When locked is the spring still fully compressed?  Draw 1ml of fermcap into your syringe (fermcap is thicker than water and therefore harder to push out, the injector should be tested with fermcap) put it in place and test.  It's a good idea to actually put 12v on the solenoid to test it, to ensure it's strong enough to release the spring.  

Attach to your AutoBrewer base. We used a 2x4 cut to a 45° angle on the flat side using a miter saw.  We shaved about 1/4" off each side to square the board and make it the same width as the base. Use 2" screws to attach to the AutoBrewer base about 1/2" from the edge.  Use 2"screws to attach the injector base to the 2x4 so that the syringe will push into the kettle.

The electronics

We are using an Arduino nano with a "relay shield" which has 8 relays attached.  This all in one board can control the whole complete auto Brewer once it is paired with temperature controllers. We use 2 inkbird Wi-Fi controllers, these are a perfect fit with their integrated online programming platform.

Other things you will need

Black and red 22 gauge wire

A phone charger block and cable

A 12v power supply

Look around the house for the power supply, or even a thrift store at the electronics section.  Our 12v power supply is from a dehumidifier we were throwing away.  You may be able to find one you already own and are not using.  

4. Wiring 

Using the 8 relay shield module with the Arduino nano makes wiring the whole system pretty strait forward and easy.

Make absolutely sure you know which wire is "positive" and which is "common" on your 12v power supply.  The "common" is also referred to as negative and or ground.

First use red 22g wire to connect all of the "common" relay terminals together, this will be a constant 12v feed to the relays that will be used for the solenoids. See (Fig 4.1)  For us this was relays 1 through 5.  This included 4 trays and the fermcap.  If you are also controlling a hoist, that wiring will be on 7 and 8, and will be explained in the hoist build page.

Next use the 22g red wire, attach 1 wire from each solenoid to one of the relays being used. See (Fig 4.2) We did them in order to keep it neat with the fermcap being the 5th relay.

Next, using the black 22g wire attach all of the second solenoid wires to the power supply common. See (Fig 4.3)

Finally, using a red wire attach the power supply positive to the vcc terminal on the Arduino, using black wire attach the common to the ground terminal. see (Fig 4.4)

Now for the signal, the Arduino looks for 5 volts on its "input" terminal to tell it to "do the next thing.". We are getting that 5 volts from our phone charger, which will be turned on and off by the inkbird temperature sensor.  

Again, it's important to be absolutely sure you know which wire is positive and which is common.  

Tie the common wire in with all the other common wires (yes, from the 12v source, all common wires from the 5v and 12v go together under the same wirenut)

Attach the positive 5v wire to "IN1" on the Arduino relay module. See (Fig 4.5)

Your all wired up, time to get to programming!

The Arduino program

Arduino programming is very strait forward, below is the program we use, you will have to be sure the correct pin numbers match the correct input and relays. Below is a guide, copy and paste these lines in the correct location in the Arduino IDE software, make the necessary changes and upload. 

We need to do a little investigating and probably change the program slightly here.  Hopefully your relay shield module came with a diagram or directions that show which pin is controlling each of the 8 relays, that would make this very easy.  And hopefully it tells which pins are connected to the "IN" slots as well.

This program as written assumes pin 1 is connected to "IN1" and the relays are connected to pins 2 through 9.  This is most likely not the case so below I'll walk you through the programming assuming you have instructions.

download the correct Arduino IDE for your computer from https://www.arduino.cc/en/software/

And follow the instructions to select the correct Arduino your using.

First you will see "void setup" at the top. Under void setup Copy and paste-

pinMode(1, INPUT); 

And change the "1" to the pin number that your "IN1" is connected to.  Thus is where your 5v will send the signal.

If your AutoBrewer is going to control a hoist then the first block of code under void loop should be the hoist control below, be sure the pin numbers match relay 7 and 8.  If your not using the hoist skip this

Hoist control - copy and paste under void loop

The next block is for the fermcap injector.  Copy the code below and paste it next under void loop and under the hoist code if your using that.  You must change the #2 to whatever pin is controlling the relay you decided to place the fermcap injector on.

The next block of code is for the scoop arms.  Copy this code and paste it under the injector code, paste it 1 time for each scoop arm you have. Change the #3 to the pin number of the relay for reach scoop arm

**Important reminder**

The Arduino program happens IN ORDER that it was written. Each time 5v is put on the input pin the Arduino will do whatever the next step in line in the program is.

Be sure you know the order that your trays will drop, they will drop in that order every time, no matter what delay you set. The timing and delays will be covered in the inkbird section below. 

Inkbird programming

The inkbird Wi-Fi devices have 2 kinds of smart programming, they call them "tap-to-run" and "automation" in this section I'll lay out exactly what each sensor does, what's plugged into it and how it interacts with the auto Brewer.

For the auto Brewer we will use both kinds of smart automations, we will create 2 "tap-to-run" and quite a few simple "automations"

For this example we are going to call our sensors

Sensor 1

Sensor 2

Sensor 3 (this is the glycol sensor if you are using it)

Sensor 1 - the relay that controls the heating element is plugged into the heating plug, the glycol pump is plugged into the cooling side.

Sensor 2 - the phone charger is plugged into the heating side, the cooling side is left empty

The first tap-to-run is very simple:

Name: signal Arduino

Control sensor 2 - set temperature to 212

Delay 3 seconds

Control sensor 2 - set temperature to -40

This will be used by the other automations to signal the Arduino.

The second tap-to-run is what kicks off the brew day, you tap this after you have mashed in but BEFORE you plug your heating element into sensor 1.

**EXTREMELY IMPORTANT** after heating your strike water, make sure your heading element is turned off or un plugged before you mash in, otherwise it could turn on and burn your bag. You will plug it back in later.

**IMPORTANT** after you press "start brewing", the first thing that happens is sensor 1 has its heating and cooling difference set to + or - 30 degrees, this ensures the heating element won't come on during the mash, unless you lose a ton of heat. At this point you need to look at sensor 1 CURRENT temperature and manually set the setting temperature to the same value.  If done correctly both relays will be off (the red and green lights on the front of the sensor will be off), sensor 1 will not be trying to heat or cool unless there is a 30° swing.

If your NOT using the hoist part of the Auto Brewer you can skip the "start brewing" tap to run.  This is basically your mash timer, it tells the Arduino to wait a specified amount of time and then pull out the mash bag and start heating up for the boil. If your doing the whole mash manually, including pulling the bag out, you can simply set sensor 1 to 212°F when your finished and your auto Brewer will take it from there.

Name: start brewing 

Sensor 1 heating difference 30

Sensor 1 cooling difference 30

Delay 1 hour (main mash timer, up to 5 hours)

Sensor 3 setting temperature 28°F

Delay 1 second (secondary mash timer, if longer than 5 hours)

Sensor 2 setting temperature 212°F (this signals the Arduino to activate the hoist the lift the mash bag, you can't put a tap to run inside a tap to run)

Delay 10 seconds

Sensor 2 setting temperature -40

Delay 2 minutes

Sensor 1 setting temperature 212

Automations

In the inkbird smart settings automations are not something that just happens 1 time, they are turned on until they are turned off and they function each time their "if" statement is true.  That can actually cause issues here because we only want the 60 minute addition 1 time! So at the end of every automation is a command to turn itself OFF so it doesn't repeat. In order to have an automation turn itself off you must create the automation without the command, name it, then go back into the program and add a line at the bottom telling it to turn off. The following is a list of automations for a 60 minute boil in the order they will activate and what the program looks like for each.

Push fermcap

If: 

sensor 1 current temp > 194

Then:

Tap-to-run - signal Arduino

Send a message

Control automation push fermcap disable

60 minute

If

Sensor 1 current temp > 205 (205 is where my system starts to boil, my sensor never gets above 209)

Then

Tap-to-run signal Arduino

Send message

Control automation 60 minute disable

45 minute

If

Sensor 1 current temp > 205

Then

Delay 15 minutes

Tap-to-run signal Arduino

Send message

Control automation 45 minute disable

30 minute

If

Sensor 1 current temp>205

Then 

Delay 30 minutes

Tap-to-run signal Arduino

Send message

Control automation 30 minute disable

5 minute

If 

Sensor 1 current temp > 205

Then 

Delay 55 minutes

Tap-to-run signal Arduino

Send message

Control automation 5 minute disable

60 minute boil

If

Sensor 1 current temp >205

Delay 1 hour

Sensor 1 setting temperature 68°F

Send message

Control automation 60 minute boil disable

You will notice all of the automations that rely on timing in the 1 hour boil, all activate at the same time, and have different delay counters.  The 60 minute timer before sensor 1 starts to cool, and all 4 scoop arm solenoids all begin counting down when my system hits 205°F, this value may be different for you, it's whatever temperature you feel is a good enough boil to start you additions.

Also, all automations include "send message" this is basically just a time stamp for you.  This way to can see exactly when each thing happens and get a better idea of how your system works.  

That's it! Your AutoBrewer is programmed and ready for its first brew day.