The amount of insulation is supposed to be 1″-2″. Cardboard is easy to replace if it gets damaged (usually by moisture).
I only insulated with one or two layers of cardboard because I was in a hurry! I wanted to see what would be the least amount of time and effort to have an inexpensive working cooker. I have always meant to add at least an inch more insulation to the sides so I could get higher temperatures on chilly days, but I am a busy mommy.
I was hoping the steel would absorb and hold heat long enough for the extra insulation to not be vital. This turned out to be true.
This cooker took two hours to build. I cooked raw chicken and potatoes the day it was made. It has been in frequent use ever since.
Hurrah for the lazy builder! I have chronic pain and have to pace myself so the easiest way is the only way I am going be able to do this, and get my overwhelmed homeschooling mommy friends to join me!
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