Step 2: Add hot water to grain and insulate for at least 60 minutes. This allows for the capture of sugars from the grains.

I was really only looking for two specific things when I selected my ice chest. It needed to be at least 60 quarts so that I had the option in the future of larger 10-gallon, high-gravity batches and I hoped it didnt look like a "cheap" piece of camping gear or something taken off a high school football field. This means I didnt want it to be orange or red, come with wheels or huge handles/hinges, or have large logos. One added bonus is that mine came with cup holders so I have a nice place to hold a glass of water and a brew while I am working.

Items needed to create mash tun:
  • $40 Cooler
  • $30 Stainless Steel Ball Valve
  • $4 1/2" Stainless Coupler
  • $10 Stainless Bazooka Screen
  • $9 1/2" Stainless Quick-Disconnect
  • $2 Teflon Tape
$95 for a great 10-gallon mash tun! And all pieces are food-safe
I went with a Coleman 70-Quart Xtreme Cooler (Blue) for $38.99 and that included free shipping. You might have to check now and then on Amazon for this item. I have seen it up as high as $80, which is way too much. And be sure not to get the version with silly wheels - you dont need it moving when boiling water is going into it. It is thick enough to hold ice for 5 days so I thought it would be good for holding mash temps too. And I wasn't disappointed. I also like the low placement of the outlet and the drainage channel so there is little liquid waste.
I literally took my ice chest to the store and laid out all the pieces so I could visualize the set-up. Also, the wall is thicker than many coolers (which is why I wanted this one). You might want to do the same to make sure you aren't going back and forth or returning things. I really dont like the "conversion kits" online because this is a better, thicker set-up than what most start out using. You might also think about buying a "Long Bulkhead Extension" - Make sure it is long enough as the cooler wall is much thicker than a standard round cooler. Also, be sure to get a stainless steel piece with National Pipe Thread (NPT) so your fittings are all compatible. I found this at my local homebrew shop but I know they have one at for the same price.
You also can save a little money if you go with a cheaper ball valve. The one I selected was higher grade steel (316 versus the standard 304) and I am more confident it will last. You can find a 1/2" Ball Valve for as low as $10
Gently remove the drain plug - these are only finger-tightened so take your time and twist it free. It will seperate into three pieces. SAVE the middle washer. YOU NEED THIS FOR LATER

This is threaded. Hold the outside firmly in place and loosen, counterclockwise, from the inside.

Lay out all pieces - the fermometer is in the photo below to indicate where the cooler wall will be

From left to right: Bazooka Screen, 1/2" coupler, stainless washer, plastic cooler washer, ball valve, and threaded quick-disconnect w/nipple (shown detached)

Insert Ball Valve into cooler drain hole. This should be a tight fit. If it isn't, you may need to use a gasket (hopefully, one or two came with the ball valve). Remember, you don't want a leak on the inside of the cooler because then liquid can go up into the walls of the cooler. This isn't really a big deal because the liquid will be so hot it will kill bacteria each time, but why chance a little extra mold flavor in your brew?

Add Cooler Washer around threads of Ball Valve and then add Stainless Washer. The cooler washer lip should fit snugly inside the cooler wall.

Tighten Coupler to Ball Valve. Use a little Teflon tape and slowly secure. Remember, tape should go on in the same direction you are going to tighten (clockwise). I only needed to hand-tighten this and it hasn't leaked. Over-tightening could crack the cooler washer or cause the cooler wall to bend too much.

Quick-Release. Apply Teflon tape to outside threads and secure quick-disconnect attachment to ball valve. Remember, tape should go on in the same direction you are going to tighten (clockwise). 

Thread Bazooka Screen into Coupler.

Fill cooler with water (outdoors, just in case) and check for leaks. Only hand-tightening should be required. If you think you have a good snug fit, but it leaks, simply take it apart and try one more time, checking pipe tape. If it still leaks after a second attempt, you may need a rubber gasket or additional washer. My ball valve came with a rubber gasket and 2 washers, but I only needed the one washer outside the original cooler washer to get a good tight fit.

Other items needed during this brewing step:
  • Stainless Steel Spoon
  • Strainer
  • Food-grade hose - this will be cut to length once you have your stand and set-up all in place


You are done with a safe and effective way of handling larger grain bills for less than $100