Expandable foam insulation

I'm looking for some insulation that i can "inject" into the lid of my 12gal cooler MLT. Currently it's hollow and i can feel the lid heat up significantly during a 60min mash.

So my plan is to inject some expandable foam or some type of insulation which would harden/dry. Does anyone know of anything or have any experience with something that could fit the bill? Preferrably something i can get at THD or the local hardware store.

A product called 'Great Stuff' will do the trick.

Alternatively, you can lay a piece of closed cell foam on top of the grain bed to minimize heat loss.

Make sure you get the low expansion version though or you'll mutilate your lid by bowing it outward. I'd recommend using the plastic straw like nozzle. Turn the lid sideways and drill a hole big enough to fit the nozzle in. Fill it a little and let it expand. Fill some more, etc etc. Give it time to fill upwards towards the hole because I suspect if you fill it all too quickly, it will try to expand sideways and bow the lid.

Just a little at a time. I did a hollow metal door frame that oozed for days onces because I got too much in it.

jcarson83 said:

Just a little at a time. I did a hollow metal door frame that oozed for days onces because I got too much in it.

Click to expand...

Lucky you, I got a good enough seal with the trim on our laundry room door that the 3x foam I used blew the frame of the door. Actually BROKE the 1x3 door frame.

Good Luck.

BigKahuna said:

Lucky you, I got a good enough seal with the trim on our laundry room door that the 3x foam I used blew the frame of the door. Actually BROKE the 1x3 door frame.

Good Luck.

Click to expand...

same here ,,,all the work to fix it then blew it up

Latex foam, not polyurethane. Latex foams are sold as "window & door" insulation. They expand less and cannot generate the pressure polyurethane will. Also, since it does not become rigid, there is less chance of a permanent wrap.

I'm a nut about insulation and nothing is better for filling mouse holes than poly, but it really needs room to expand.

Thanks, all, for the advice.

comp said:

same here ,,,all the work to fix it then blew it up

Click to expand...

Destruction due to abuse = COOL!
Destruction due to Neglect = SUCK!


Ya...Normally I like blowing **** up!

+1 on Great Stuff
I used it for a project last year in my Heat Transfer lab, sweeet stuff.

hey... I know this guy (this is Tommy)

I filled the lid on my Ice Cube with Great Stuff. Bobby is right, go slow and only fill it partway.

I'll be doing this to my 10 gallon Igloo Industrial this weekend. I'm likely going to use the Great Stuff, but I'll drill an escape hole on the opposite side at the top and inject my foam from the bottom. Likewise for the lid.

This latex foam sounds interesting. I may look for that as well.

Thanks for the advice on the Great Stuff. Worked like a champ with just a little oozing. But i'm fine with that because i know i got all the nooks & crannies. I'm banking on better heat retention now.

Yep, those coolers just aren't made for heat. They figure the insulated sides and bottom will keep your stuff cool, and they are right. I really like how us brewers are so resourceful and look at something like that and go, " That would make a great tun if I insulated the lid." Then you have a bitching mash tun that didn't take you 3 months to build and costs all of a bill when everything is said and done. Well done!!