Making a Mash Tun - All Grain Brewing

I've brewed 6 batches of been since January, all have been from extract kits.  Extract kits are great, they make great beer, and cut down on a few complex steps.  I've found it helpful to start with extract kits, it's good to cut down on the variables at first.  Lord knows enough can go wrong in the beer making process, why start complex and get frustrated?  Plus, all grain batches require a few more items, start up cost can be minimized by starting with extract kits.  Once you are ready to get more technical and get a taste of what a all-grain brewing is all about, pick up a Partial Mash Kit.  It uses a mashing process and some extract, you'll get a feel for what all-grain brewing is all about.  Northern Brewers Speckled Heifer is a good partial mash kit.

I'm at the point where I'm ready to make the switch to all-grain, so the first thing I needed was a Mash Tun.
The Mash Tun is a vessel in which barley is steeped to extract the fermentable sugars from the grain.  I consulted Palmers book How to Brew (my go-to source) and did some on-line research before I bought a thing.  Palmer spends a chapter talking about Lauter efficiency, which I would recommend you read to understand how to build your manifold.  There is MUCH more to it than simply putting some copper pipe together.

I am using a simple 7 g/28 qt cooler.  I bought one that had no drain plug, I wanted to determine where to put my ball valve vs. have it dictated to me.  I found that Home Depot had the parts I needed, and Menards didn't.  When I talked to the guy in plumbing at HD, the moment I mentioned a cooler and ball valve he said, 'Home-Brewing?'  He said someone comes in every week looking for parts to build a Mash Tun.

Read up on Manifold designs in the Palmer book and set out to buy your materials. A simple cutting tool is used to cut your pipe.   There are two grades of copper pipe (maybe more), one has a thicker wall, one thinner.  no need to go with the thick wall, nothing will be under pressure. I used 1/2 inch copper pipe, the kind that has the thinner wall.

I drilled a 3/4 inch hole in the cooler to fit a threaded plastic pipe that poks through both sides of the cooler.  I used a 2 inches long, 1/2 inch plastic threaded pipe (I believe it was for a sprinkler system) as the cooler was 1 1/4 inches thick, I SHOULD have gone 2.5 inches!  I had very little thread to spare.  I used replacement garden hose gaskets for my washers.  The hole ended up being drilled off center to accommodate the manifold (see photo below).

It makes sense to have the outgoing hole as close the the floor of the cooler as possible.  But since I only went with a 7 gallon cooler, there really wasn't much room on the floor to keep everything at one height, you'll see why in my manifold design below.

 Outside the cooler, the ball valve attached simply to the threaded plastic pipe.  I used a 1/2 inch x 1/2 inch barbed nozzle as my out.  Every connection was snugged up with a crescent wrench.

14 x 5 

  I cut slots on the copper piping that runs the length of the cooler.  I did this by holding the pipe in a vice and using a hacksaw to cut halfway through.  It takes some time to do this, but if you have some nice music to work to, it goes quickly.  I cut slots every 1/2 inch along the length of the manifold.  The slots will be facing the cooler floor when the manifold is in place.

Don't solder the manifold together!  1) you want to be able to take it apart to clean it, and 2) solder has a bunch of chemicals in it.  I crimped the copper tubing ever so slightly to create a friction fit at every connection.




It all fits together nicely!  This design means that some of your sweet wort will be left on the bottom of the cooler, after all, gravity can't make it all flow up and out.  Not a big deal, I think.  I'll let you know once I've completed my first batch.

Hope this helped...  It's trial and error, I went through 3-4 designs before settling on this one.  Cheers! -Chris