BeerMumbo: Try this simple homebrew mash tun box cooler conversion

Stepping your brew game up from extract to grain is a smart choice. Not only will you find it much cheaper to brew a batch of beer, you will also find the beer tasting much better too.

After all, beer is a product from extracting grain. Buying a commercial mashing system can prove expensive and is not within the budget of your average home brewer.

What is the solution?  Bust out that old 50 quart cooler and make it into an efficient mash tun cooler.

The total investment will only be $40 if you already have a cooler and $100 if you do not.

Savings?  How about $10-$20 per 5 gallon batch of beer.

Step 1:
Find a 45-55 quart box cooler that has a drain plug.

Step 2:
Buy a 1/2 inch ball valve and a 1/2 male/male extension piece from your local Home Depot or Lowes.  Measure the thickness of the cooler wall before buying this piece.  You want it just long enough to create a snug fit from both sides when its all said and done.  A little thread on each side is ideal.  Stainless steel would be ideal but brass works just fine.

Step 3:
Remove the drain plug and its components.  It should be a simple threaded piece.  Save the rings because you will need them.

Step 4:
Install the new ball valve and former fittings.  Your cooler should look like the one below.

mash tun conversion

Now that you have the exit piece in place you need to put together the inside of your mash tun OR as I call it…the balls of the mash tun.

Step 5:
You have two options for this piece of your mash tun and both are considered efficient.

Option 1
a. buy a stainless steel washer hose and snip both ends of the hose.
b. work the stainless steel coil off of the hard plastic hose on the inside.  Be careful to not cut your hands doing this.
c. on the inside you will need a 1/2 “T” splitter with two 1/2 nipples.
d. coil a copper wire small enough to fit inside of the washer hose and then connect to your T splitter

mash tun conversion

Option 2
a. go to your local homebrew supplier and buy a boil pot strainer.
b. hook it up to the extension piece that is connected to your ball valve on the other side of the cooler. 
c. buy some rubber weather stripping and line your lid all the way around with it.  This is much better at holding in heat than the plastic on plastic connection.

mash tun conversion

You are now ready for some all grain beer brewing.  Welcome to the world of brewing real beer. Cheap investment yet a good one.

mash tun conversion

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