Mash Tun Build – Homebrew

Funny looking mash tun?

I’ve set myself a goal for the coming months, a DIY mission that many homebrewers embark on.  Building some or all of your own kit is something that is likely to save you some money when starting out, but if it doesn’t then hopefully there is knowledge to be banked along the way.  Understanding my kit and being able to maintain it is something I’m interested in, but I understand it’s not for everyone.  It’s also a lot of fun, honest!

To date I have inherited a shop-bought 5 gallon boiler and a few plastic buckets.  Having experienced first-hand what it’s like to use one boiler as a three-in-one; HLT (Hot Liquor Tank), Copper and Mash Tun I was keen not to experience it again.  With some instructions from the folks on The Homebrew Forum I managed to build my own mash tun.  It’s been done and documented many times by other brewers, but here’s my attempt:

I built this back in May 2011 and have used it for three brews.  The pictures aren’t great and I’ve not taken a shot of each stage, but I was concentrating on building the thing and the camera work came second.

There are a few ways to build a mash tun, but I decided to convert a cheap 24L coolbox and a copper manifold.

Total cost including materials:£25

Tools I Used: A drill & circular drill bit, copper pipe cutter, hacksaw (or some sort of angle grinder if you can get hold of one), I also borrowed a pipe bending gizmo which I needed to accommodate my ‘design’, pliers, files and wire wool.

Stage 1: Assembling the Tap

Measured up for the tap and cut a hole through the outer/inner casing of the coolbox. Threaded the tank connector through from the inside-out and using a small section of copper pipe attached the ball valve tap (all 15mm fittings).  I added a copper elbow joint to the end of the tap to form a spout.

Stage 2: Constructing the Manifold

First I measured up inside the coolbox to see what size manifold will fit comfortably and cut the copper pipe to fit. I had to bend the pipe connecting the tap and the manifold to allow the manifold to sit flat against the floor of the coolbox.

Fitted the copper pipes, T-joints and elbows together, secured the manifold in a vice and went about cutting as many slots into it as possible, cutting approx half way through the pipe. I used a hacksaw mainly, but did use a Dremel drill with a cutting tool on it (although it just overheated too often and because of the steamed up safety glasses I managed to cut some bad angles!).

Stage 3: Fitting the Constructed Manifold

Simply connect the pipe from the manifold into the internal tank connector (inside the coolbox, with the slots facing down).  Testing found no leaks and the manifold drained the water effectively with a small dead space of 0.5L  (i.e. the amount of water left in the tun with the tap fully open).  Once happy with your mash tun and manifold, then some people choose to solder a few of the joints to hold the manifold together, but it is possible to lightly nip each of the joints together, which allows easy cleaning.

Hope this is of use to someone thinking of doing the same.

Next up:  I’ll be attempting build an Immersion Wort Chiller and a 30L plastic boiler (can’t really call it a copper can I!)

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