Possible to reform buckled cooler interior?

[TimpanogosSlim]

I have a 10 gallon rubbermaid cooler mash tun that i bought used from another local member here (thanks!) that has buckled inward, like they all seem to.

There seems to be some sentiment that this is what happens to all of them, and that eventually it will split. It came with a backup cooler so I'm not losing any sleep over that, but I'm annoyed that i have to remove the valve from my mash tun to remove the false bottom for cleaning.

I searched but did not find specific references to repairing the buckle, just references to the impossibility of repairing the eventual cracking.

I wonder if i can just heat it up with my heat gun and use say a stainless steel salad bowl or something to push it back to a flat position?

Has anyone tried this?

 

[DeafSmith]

I don't know if you can reform the interior, but if you try it, I think you will have better luck if you can very slowly heat up the entire cooler first so that the heat can soak into the exterior and expand it as much as possible before trying to reform the interior. I believe the buckling is mainly due to people dumping hot or even boiling water into a cold cooler to preheat it. The interior lining expands from the heat and has no where to expand to because the middle and exterior of the cooler is still cool and unexpanded. Since the interior lining is now bigger (greater diameter) than its enclosure, it has to buckle. So trying to reform the lining by heating it in an otherwise cold cooler is probably doomed to failure (and may not work even in a hot cooler).

I never dump hot water into my cold cooler (also a 10 gallon RubberMaid). I heat it very gradually. My kettle where I heat my water is lower than my MLT and HLT, so I use a March pump to move the water, and I have a switch to make turning the pump on and off easy. I start heating the water, then pump almost all the water out of the kettle to the cooler, then turn off the pump and let the water slowly drain back through the pump into the kettle. By the time all the water has drained back, the water in the kettle is about 20º F hotter than before. I repeat the pump and drain until the desired strike temp is reached. This process heats my cooler slowly, giving it time to expand gradually. So far I have seen no signs of buckling or cracking, but only time will tell if this works in the long run.

 

[TimpanogosSlim]

Well, it was buckled when i got it, which was probably why the seller only wanted slightly more for that one than the cost of the fittings it came with. He said he'd only been using it to store strike water.

So far I am batch sparging. Typically i just dump 170f(ish) water into the cooler, then dump in the grain, stir a bit, then take a temperature reading (usually mid to high 150's after adding grain), and lid up.

When i say dump, i mean dump. I use a 1 gallon pitcher to transfer the first couple gallons and then just lift the kettle and pour. I have weldless kits for the kettles but have not installed them yet.