Cardboard and Duct tape Solar Oven

This instructable is about a solar oven I made out of an old picture frame, two cardboard boxes, some duct tape, aluminum foil, white glue and crumpled newspaper. You will need to find a picture frame. I used regular glass but tempered glass would be better as it gets very hot and could shatter if you spilled cold water on it.  I think I used about a 12 x 14 frame, not sure as it was a few years ago. What ever size glass you find will decide the size of the inner box and the outter box should be 2-3 inches larger. You need to cut a hole in the larger box to fit the inside box then crumple up some newspaper and pack between them.

Step 1:

Next thing after the box is in the hole and newspaper is packed between them is to tape it up.

Step 2:

 

Next I lined the inside with aluminum foil using white glue. After I tested it I extended the foil out of the box and over the top. I also reversed the door so the tape was on the outside. Sorry I have no photos of the modification.  I used two layers of Duct Tape for a hinge on the back of the picture frame.

 

Step 3:

Next are the reflectors. I made them out of cardboard but corrigated plastic political signs would work perfectly (After the election and with permission)   I cut out the cardboard and applied white glue and flipped it over on to a sheet of foil shinny side down. Trim the foil after it dries and add Duct Tape around the edges. The best angle is around 60 degrees off the glass. I was just learning when I made this so my angle was off so I corrected that later, again no pics.

Step 4:

Time to start testing. I tryed different methods of aiming the oven by blocking with rocks, bricks or leaning it against something. Found it didn't do a very good job of baking rolls as they came out hard as a rock but I cooked a chicken breast in it in 2 1/2 hours. I had to tweek the reflectors to get the right angle for the sun to focus on the pan. I poked some holes and used a shoe lace to adjust the light beam.

Step 5:

 

 

I poked a hole through the back and inserted a probe type thermometer. I had it up to 280 degrees when we was in Arizona on a nice February. We used this oven for a couple weeks then I built "The Solar Baby"  a pivoting, gimbled solar oven, I made 2 instructables on Solar Baby 1 and 2, made mostly with recycled parts and reach 350F. This project is what got me hooked on solar cooking. We have been on the road in our motorhome 3 years and only use our propane oven on cloudy days.

By aleutianwind

Source: instructables.com