The other day I decided to fill my hollow mash tun lid with expanding foam insulation (That Great Stuff stuff). Thought I'd pass on some tips:
1) Wear gloves and put plastic on your workbench
2) Drill at least two holes so the trapped air can get out
3) The can has a little little plastic tube/applicator thing. When you put that into the hole you drilled, don't move it from side to side - it'll break off (as I learned the hard way)
4) After the lid was filled, I balanced the lid across the top of a garbage can. That way, as the foam expanded and leaked out the holes, it just fell into the garbage.
5) If you drip some on your workbench/floor, leave it. After it cures, you can just pop it off the workbench/floor in one piece. Trying to wipe up uncured foam is a PITA and it makes a bigger mess.
1) Wear gloves and put plastic on your workbench
2) Drill at least two holes so the trapped air can get out
3) The can has a little little plastic tube/applicator thing. When you put that into the hole you drilled, don't move it from side to side - it'll break off (as I learned the hard way)
4) After the lid was filled, I balanced the lid across the top of a garbage can. That way, as the foam expanded and leaked out the holes, it just fell into the garbage.
5) If you drip some on your workbench/floor, leave it. After it cures, you can just pop it off the workbench/floor in one piece. Trying to wipe up uncured foam is a PITA and it makes a bigger mess.