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In this series, I will use SOLIDWORKS to design a keezer for use in delivering cold homebrewed beer from several kegs at a time. The goal is to design and eventually build the best delivery system possible to meet our requirements. One could even say that we will be following an adventure in beer engineering.

The following will be in store:

Part 1: Requirements & Modeling – Setting design requirements and using SOLIDWORKS to model all the core parts.

Part 2: Keg Layouts / Analysis – Putting all the pieces together to select the optimal equipment for the project.

Part 3: Framing the keezer – Using SOLIDWORKS Weldments to turn it into a wooden work of art perfect for any rec room.

Part 4: Connecting our Lines – Using Piping & Tubing to connect all the beer line in addition to CO2 line components.

Related YouTube Videos:

Global Variables and Configurations

Welcome to Oktoberfest at Hawk Ridge Systems! To kick off our Oktoberfest series let’s start by facing the facts and owning up to a little something that we all do here. When you know how to use SOLIDWORKS and have a project in mind at home things can get outright nerdy, and you can and will make use of its tools to plan out every little detail. It’s not that we like to swat a fly with a hammer so to speak, it’s that we absolutely love spending time in SOLIDWORKS. Combine that with a hobby or passion you have at home and we really see how truly nerdy things can get.

In my case not only am I a SOLIDWORKS expert, but I am also home brewer. At home I love crafting beers and developing my own recipes, and I do so with equipment I’ve personally put together for all grain brewing. When you brew beer all grain you are brewing with pretty much the same process every functional brewery has to do. It’s a very satisfying hobby not because I can make beer for a few dimes a bottle, but I get to flex my engineering brain in numerous ways. Being a home brewer is a lot like running a manufacturing facility that subscribes to lean manufacturing principles. You are always planning your next big upgrade with the goals of achieving:

 a) Higher yields – it’s nearly the same effort to make twice the amount at once.

 b) Higher quality – making tastier beer, normally involves new equipment and processes.

 c) Less effort – spending less time for the same results, a brew day can be a very long 8 hours.

With that said, my next adventure in home brewing is to build my ultimate homebrewed beer delivery system, a keezer! For the uninitiated, a keezer is essentially a chest freezer that has been converted into a refrigerator to not only keep kegs of beer cold, but to serve the beer using taps as well. To avoid confusion, a keezer is a much larger and beefed up version of a kegerator. In Part 1 of this series I will get things started by setting up some design requirements and bringing the pieces together into SOLIDWORKS.

1.0  Design Requirements

First off, these are the requirements of my ideal keezer:

  • Capacity must hold 4 to 6 Cornelius (aka “Corny”) kegs of 5 Gal capacity each. Think big, remember you can always use a tap for soda pop and another for white wine even.
  • Must have the option to include a 20 lb. or 10 lb. CO2 tank inside. The 20 lb. tank would have to sit on the floor, and the 10 lb. would have to go on the compressor step.
  • A very nice to have is some space for one 5 Gal carboy for the purpose of lagering
  • The ability to deliver two unique carbonation pressures

 

2.0  Data Collection

I traveled out to some big box and appliance stores with my handy measuring tape and a pen and paper and collected the following critical information from a couple of freezers. Our goal here is really to find one that fits corny kegs as efficiently packed as possible. We really only care about the inner dimensions for this, but future articles will require all dimensions.

We are presented with the following options based entirely on what I actually saw in the store.

  • Kenmore 5.1 cu.Ft
  • Kenmore 7.2 cu.Ft
  • Frigidaire 9 cu.Ft
  • Frigidaire 11 cu.Ft

3.0  Modeling It All

We will need models of all the freezers, a 5 Gal corny keg, a 5 Gal glass carboy, and a 10 & 20 lb. CO2 tank. Let’s begin with the small pieces.

3.1  Corny Kegs

Luckily for me I was able to locate a spectacular model of a 5 Gal corny keg on www.grabcad.com, import it into SOLIDWORKS and essentially just assign a few colors to sharpen it up a bit. Checking on the dimensions, this looks exactly what I would expect, so this is a great model. As a huge bonus, it even has the ball lock connections for both the CO2 and beverage lines. Something we will really make use of when we use SOLIDWORKS to do the piping and routing later.

3.2  Carboy

For the carboy, I was not so lucky finding a good one online and will have to model this myself. Throwing together a quick model of a 5 Gal glass carboy I end up with this. I am okay with this not having every single detail, since it’s really just the overall dimensions I’m interested in representing. But if I actually needed every little detail, I would probably have to go into using the surfacing tools. Remember this requirement is a “nice to have”. If I am brewing a lager it is very nice to have the option to use the keezer to double duty as a lagering chamber. Lagering by the way is the process of holding your beer at close to 0°C as possible typically for a given duration after fermentation is complete. It drops all sorts of small particles out of the beer and drastically smooths it out.

3.3  CO2 Tanks

The CO2 tank was similar in that I had to model this myself, and since I have 2 sizes guess what? We can use configurations! Because I am doing piping and routing further down the line, I will definitely want to spend further time building a better model with a gas valve and connection point. But for now I think this looks very similar to my 20 lb. CO2 tank I already have at home.

3.4  Chest Freezers

And now for the main focus of our sizing analysis, and that is the freezer itself. All chest freezers have the same basic design, so we actually have a perfect way to utilize configurations again. One thing is I absolutely love is using global variables to control overall parameters in SOLIDWORKS. If you take the time to relay your major design parameters through a global variable it will give you a single nice spot to come and change everything. Yes, you could just configure the dimensions directly, but this is just a way you can do that with global variables. And here is a huge tip, this is also the best way to tackle parameters which will change for when you take your CSWP exams! The second you see a value that you know may change on you, stop what you are doing and head directly into the equations table. Before I even model a thing, I open my table and enter the values for the 5.1 cu. Ft Kenmore freezer.

Then as I model the freezer, I make sure to set my values equal to the proper global variable like so:

My freezer really only has 2 features, a boss extrude to define the whole freezer itself without the lid and then a cut extrude to hollow it out. But it’s the configurations where all of the SOLIDWORKS magic happens. I create a configuration for each freezer and then insert a design table where I can fill in all parameters. Unfortunately, when it comes to global variables, you pretty much have to use a design table right now. I say that because it works, but it’s not necessarily pretty. Here is the 11 cu. Ft Frigidaire to see the final product.

 

If you are interested in seeing a video I did on setting up these configurations and tying the global variables into them, please CLICK HERE.

Well, thanks for joining us in to this first installment of Oktoberfest at the Ridge, I hope you’ve enjoying this as much as I am. Stay tuned for our next piece in this series where we put all the pieces together to do some keg layouts in SOLIDWORKS and pick the optimal equipment to move forward with.

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