Other than the top window and seals, the box is the most important part of the solar oven project. Maintaining a high internal temperature requires a good seal on top, and a well insulated box.
Last week I put together the solar oven box with sheet metal, high heat paint, and the corner guards . This week I am installing the insulation, and the outside panels. After that we’ll get everything ready for the finishing touches.
Difficulty: This part of the solar oven project is very easy. With the frame and interior box already assembled, it’s time to add some insulation and the outside panels.
SHTF Value: Having as many ways to cook in a disaster is always a plus. There are not many options available for dehydrating or cooking food in an oven.
Cost: Again, how much this costs really depends on the materials you use. I used Foamular for the insulation, but there are lower cost options available.
Tools Needed: Drill – 3/16 Drill Bit – Skil Saw – Drill Gun – Straight Edge
- 2ft X 4ft 1/4″ MDS Board (2) $8 Each (Website only shows 1/2″)
- 2ft x 2ft Foamular Insulation $6
- 1 5/8″ Screws $6
- Kilz Primer Paint $9 (Any Paint Will Work)
- Rust-Oleum High Heat Spray Paint $4 (1 Can for Entire Project)
You may have some of the items listed above, and a couple you will have already purchased. You may already have some screws and paint at home, and you will have the high heat spray paint left over from the interior solar oven box.
Cutting Cardboard Backing
I wanted to have a little separation between the interior sheet metal and the insulation and I decided to use cardboard. I just measured each of the solar oven frame pockets and then used these pieces of cardboard as templates for cutting the insulation.
For the insulation I used a 2 x 2 foot piece of Foamular which I purchased at home depot for about $6. Some regular insulation has asbestos in it and I didn’t want anything that would give off toxic fumes and bad smells.
Other options for insulating a solar oven are news paper, straw, styrofoam, or even using a few pieces of cardboard stacked together. The Foamular is much easier to work with than any of the other options though.
Trimming the Insulation
Once I had the cardboard and the insulation cut out I put everything in place. I cut the insulation a little short in a few spots and just used scraps to fill in those gaps.
Cutting the Exterior Panels
Cutting the exterior panels of the solar oven was fairly simple, but the back panel isn’t exactly the height of the frame. Because the top rail of the frame is flat (not angles like the front rail) I needed to cut the back panel 1/2 taller than the frame.
To make sure all the exterior edges fit together make sure and cut the 2 side panels first, and then the front and back. For the front and back you will need to measure the width of the box with both side panels on or you will be a 1/4″ short.
As you can see in the image above, when I add the top of this solar oven, it will sit flush with the back of the solar oven. I explained this in a little more detail in the video.
Painting the Exterior Panels
If you just use spray paint directly on this MDF board you are going to need a lot. This unfinished board really soaks up the spray paint. I used some Kilz primer on these panels before I applied the spray paint.
You can use any spray paint you like, but because I still had a half can of the high heat paint I used that to finish these panels off. I also figured that this high heat paint would hold up better in the sun, and black also absorbs heat.
Installing the Solar Oven Panels
With everything done it was time to attach the exterior panels to the solar oven. I did drill a couple of holes in each panel before I painted them to make sure everything was in the correct position, although I’m not sure how necessary this was.
How many screws you use is up to you, but I suggest at least 3 screws on each edge of all 4 panels.
The final step in building this DIY solar oven is putting together the top and all the accessories. Next I’ll be installing the top frame, the Plexiglas, the hinges and the reflector panels.
After that it’s testing time! I can’t wait to see how this solar oven stacks up against the All American Sun Oven. You can view the next tutorial as well as all the other steps using the links below.