I am a regular over at www.homebrewtalk.com and found this forum to be a great resource for everything related to the homebrewing hobby. I’ve been wanting to hack up my beverage cooler after the first use when I did the Arrogant Bastard Clone. Give it a bit of an overhaul so to speak. I found a great thread with vivid instructions on how to assemble your own mash tun, here are the results:

Tested with plain water (4 gallons for 3 hours) no leaks! May test with rice hulls or oatmeal flakes next.