How to make a Funnel Cooker

How to make a Box Cooker

Cut the cardboard into a 4 foot by 2 foot piece, with a utility knife. Make a paste with glue and water, equal amounts. Spread this over the cardboard with a paint brush. Take the aluminium foil and spread it out over the cardboard, make sure it is as smooth as possible, with the shinny side up. Roll the cardboard into a funnel shape and duck tape it on the outside. Take the box and line the bottom with tinfoil and set the funnel inside the box.

Cut the cardboard with a untility knife, 2 sides need to be 50cm across the top, 15cm across the bottom and 60cm high. Two other pieces need to be 65cm across the top and 30cm across the bottom and 60cm in hight. Now take the glue and water and make a mixture of even amounts of both. On each piece of cardboard use the paint brush and cover the cardboard with the glue mixture. Cover the cardboard with the foil, the shinny side needs to be up. The foil needs to be smooth, as few wrinkles as possible. Take the four panels and duct tape them on the back side, alternating pieces, then pick the pieces up and join the panels together, with the reflective panels on the inside. Fill the cardboard box with shreaded paper, place the reflective panels in the box and duct tape the flaps of the box to the reflective panels. Paint a cake pan black and put it inside the box cooker.

The Experiment

To see which cooker works better we took two mason jars that we had painted black (to absorb the sun) and filled them with 2 1/2 cups of water. We punched a small hole in the cover of the mason jars and inserted a meat thermometer in each one. The water temperature was the same in ear jar. We took the jars and put them inside of a plastic oven cooking bag that we had blown air into (to hold in the heat.) We took our solar cookers outside and sat the mason jars inside of them.