I've seen a few videos online of people making Rocket Stoves using plastic 5-gallon pails as the outer shell. This was interesting to me as I would think that the plastic would melt pretty severely and eventually all of your insulation would leak out. The videos I've seen did not show that as far as I could see, so I decided to try it out for myself. Instead of using a 5-gallon pail with thick plastic I thought I'd use a normal juice jug that everyone has in their trash...In my case I used an Arizona Ice Tea jug which had the added benefit of a handle. The plastic of the jug is considerably thinner than a 5-gallon pail, so I expected it to melt pretty bad. I constructed the usual soup can "L"formation this time having a two-can fuel input section and a two-can stack plus the addition of an Arizona Ice Tea tall can to extend the stack and give a better vacuum. I made all my cuts and put it all together using normal play box sand as my insulation layer.
I fired it up and it worked great! Probably the best one I've made yet. After letting it burn and feeding it for about 2 hours it was still performing strongly...there was some melting of the jug around the stack and the fuel input cans, but not enough to let the sand spill out. I'm pretty shocked that this worked as well as it did, and with the cool little handle you can actually pick it up and move it around while lit. (Although I wouldn't recommend doing that for safety reasons.)
So, long story short...plastic is a reasonable option for the outer shell of a Rocket Stove. Probably won't last forever, but it's more readily available than a paint can sometimes and easier to cut.
-Jacob
