This is the mash lauter tun. It's just a plain old Igloo ice cube cooler with a 1/2" ball valve.

Inside I soldered some copper fittings together to make this. I just attached some stainless steel hose braid from a toilet supply line.
This is what I used to make the bulkhead fitting on my mash tun. It's a 1/2" ballvalve, 1/2" pipe nipple, 3/4" SS washers, O-ring, and a flair fitting.