Back to the drawing board

[beerme70]

Well, crap! Bought a 15 gallon and 30 gallon drum to make a mash tun. Used 2 part expanding foam from Illstreet Composites, and I'll tell ya, that stuff works GREAT! Too good, actually. You see, it wound up caving in the sides of my 15 gallon drum, sooooooooo, I have to come up with a plan 'B'. I thought I had thought everything through, but there is always that one instance where you have an "oh, I didn't think of that" moment. I could just go with a 60 quart rectangular cooler from Wally-World, but I would really like to with a round one, for the sake of uniformity (I'm kind of weird that way). Anyway, I just thought I would share.

 

[jakwi]

Any pictures? I bought the exact same barrels to do the same thing. What would you do differently? I was debating about filling the 15 gal with water and putting the plugs in, non compressible fluid. Or possibly just wrapping it in that aluminum bubble wrap to avoid the whole issue.

I have a 10 gal igloo MT, but it is right to the brim for my 10 gal batches. Funny that we came to the same solution.

 

[day_trippr]

Is there a reason why one could not use expanding foam but apply it in successively laid bands of say a few inches high each, allowing each to cure before applying the next? That should allow the foam to conform instead of crush.

Filling and capping the inner vessel sounds like a great idea as a back-stop, but I still wouldn't tempt fate and fortune by filling the entire gap in one or even two shots...

Cheers!

 

[jakwi]

sounds reasonable, Might take a little longer, but I would think it would work. It makes you wonder how they put together coolers? I have to imagine they dump the mix in and put it together, otherwise production time would be to long.

 

[LandoLincoln]

...or just take a bunch of 1x1 pieces, cut them to length to fit the inside diameter of the drums and use those to brace the walls of the drum while the expanding foam does its thing.

 

[day_trippr]

sounds reasonable, Might take a little longer, but I would think it would work. It makes you wonder how they put together coolers? I have to imagine they dump the mix in and put it together, otherwise production time would be to long.

It seems likely they use a non-expanding foam.

Cheers!

 

[jakwi]

You know I don't know for sure, but it looks like expanding foam, it's hard to say I guess

 

[Onkel_Udo]

Well, crap! Bought a 15 gallon and 30 gallon drum to make a mash tun. Used 2 part expanding foam from Illstreet Composites, and I'll tell ya, that stuff works GREAT! Too good, actually. You see, it wound up caving in the sides of my 15 gallon drum, sooooooooo, I have to come up with a plan 'B'. I thought I had thought everything through, but there is always that one instance where you have an "oh, I didn't think of that" moment. I could just go with a 60 quart rectangular cooler from Wally-World, but I would really like to with a round one, for the sake of uniformity (I'm kind of weird that way). Anyway, I just thought I would share.

What is the quoted expansion and temperature at cure for that stuff. Two-part foam tend to be either highly exothermic or massively expansive or both. For example, two-component closed cell foam in the the two 20# tanks is designed to expand 8-to-1...which is why the nozzles are normally calibrated for an 1/8" coverage.

Heated line commercial closed cell is normally formulated for a 14:1 expansion rate so that a normal two-coat application slightly over-fills a 3 1/2" stud bay.

Low pressure and low expansion foams exist but you still much better doing multiple lifts.

 

[beerme70]

I can't recall what the stated expansion rate was. The problem was is that it was a little chilly in the garage, so the expansion was going to be less than advertised. No worries, though. I bought another drum, cut the old one out, trimmed the foam down, and inserted the new drum. Fit like a champ, and it works great! Zero degree heat loss after an hour mash, so I definitely can't complain.

 

[jakwi]

Wow, it looks really good. Just a couple of questions. I was looking at Illstreet foam; did you get the 2lb density or a higher density? and Why did you insulate over the outer barrel? Was the foam insufficient by itself? oh and what did you use for the lid?

 

[Spartan1979]

The stuff you buy in the cans comes in two types, regular and minimal expansion. The minimal expansion is for around doors and windows so that the frames aren't pushed out of square causing the door/windows to bind. Maybe you should try that type.

http://greatstuff.dow.com/products/window-and-door/

 

[beerme70]

Wow, it looks really good. Just a couple of questions. I was looking at Illstreet foam; did you get the 2lb density or a higher density? and Why did you insulate over the outer barrel? Was the foam insufficient by itself? oh and what did you use for the lid?

I used the 2 lb. stuff. I put the reflectix on the outside purely for aesthetic reasons. I had a small chunk of 2 inch foam padding that I put on the bottom to keep the inner barrel raised up. I cut the center out of the lid of the 30 gallon barrel, which just so happens to be the same diameter of the 15 gallon inner barrel. One kit of the foam will not fill the void completely, so you'll have to mix up the second kit. My mistake, I believe, is that 1) I poured too much in the second time, and 2) I put the lid on to keep the inner barrel more centered, and the excess foam had no where to go, thus collapsing the inner barrel. If I had to do it all over from the beginning again, I would use about 1/4 of the second kit, and if I needed more, mix another 1/4, etc. until the cavity was filled.