As I said before?????Liquid nails..its cheap, it seals, and it works.Inside, and out.2-3 tubes, and your fingers at work, is all that is needed.Works just fine, and has for me for the last 15+yrs.//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gifLiquid Nails doesn't expand. They even make a specific type for slick panel board such as MDF. Also, not everyone uses MDF to make enclosures.. so Liquid Nails (the proper type) is often used and works very well. Especially if you don't have the right saws to do everything. It's great for filling voids.