What do you use for a mash tun?

Coleman 70 quart Xtreme. My 52 quart Xtreme did the same delamination thing, but it was still usable (I just upgraded to bigger so I could do bigger batches.

 

10 gallon Igloo round cooler. It seems to be doing well, and the top is a press fit, rather than a screw-on type. It still seems to seal well.

 

Coleman extreme 36 qt. perfect for 5 gal batches as it has limited head space, but easily accommodates 17 lbs grain for big beers. I always warm it up with half gallon of nearly boiling water and it only loses 1 degree over 60 min mash. Great purchase.

 

I have seen the 10 gallon Rubbermaid get kind of wavy on the inside after a period of use as a mash tun. Mine has yet to do that after a couple of years and many batches (please don't make me try to count). Although I picked the Igloo brand mostly because it had the press-on lid and not the screw top lid at the time, and I am happy with it so far.

 

However, I will also add that you can go larger than 40 quarts with the rectangular coolers, and do so less expensively.

 

Converted keg with false bottom-I've mashed 42 pounds of grain at a time for a 10 gallon batch of Imperial Stout but sparging takes forever and I lose a lot of efficiency.

 

All I can say is wow...that is a lot of grain to sparge.

 

Now I split it into 2 batches-30 pounds in the keg, the rest in my cooler mash tun that I've used exactly 3 times in 3 years.

 

I have a 10 gallon Rubbermaid...there's a small bulge ( about 1" in diameter) on the inside that runs from top to bottom, but I've had no issues. The other 10 gallon Rubbermaid I use for sparge water has had no issues.

 

I use a 10 gallon coleman round cooler. I average 1 batch per month and have been using this for 3 years. It is still in very good shape. The most I have put in this is 23lbs. Take care.

 

I used to use a 10 gallon Home Depot cooler. Now I mash in a steel kettle and use the cooler as a lauter tun. I did this to avoid having to add boiling water for mash outs and step infusions. With a thermometer in the kettle I can maintain and raise temps without altering the grain:liquor ratio. It also provides a greater headroom for sparging.

 

60 gt cube cooler, used it twice yet, with 20 pounds of grain, thinking about using something smaller for normal sized beers. I have access to a five gallon igloo cooler, not sure if I can modify it though.

 

Converted keg w false bottom, direct fired, 90% of the time.
I still go back to my 50qt xtreme cube cooler tun occasionally, with braided hose. It has many many batches in it, but it has never bulged or anything like that.

 

Converted keg with false bottom. However, we also have a rectangular cooler (40 qts I believe) that we use to make 5 gallon batches on the side when doing 10 gallon batches simultaneously. If just doing a 5 gallon batch (no 10 gallon batch at the same time), we use the keg with false bottom as we get a more predictable efficiency out of that.

 

I use a green 50qt rectangular coleman. I can fit 30# of malt in it, uncomfortably. However I do not have a warping problem. In my previous coolers I did get some warping. On this one I don't get any. It's probably about 5 years old now. I plan to build a round SS mashtun or a wooden one for my next tun.

 

I using 5 gal Lowe's cooler, for 18# of grain you can use Igloo 10 Gallon
If you like I can upload some pictures of the inner piping.

 

Blichman Boilermaker 20 gallon W/ False bottom (Can't beat the button louver desing for efficiency and plug resistance in my opinion) and autosparge ball.

It can handle all the grain I can throw at it, the autosparge ball is incredibly easy to set and forget and it is a very efficient system.

 

Coleman XTreme 52 quart. Probably about 50 batches with this tun, with no warping (since you mentioned you've had that problem with rectangular coolers).