This is an exercise in recycling and alternative energy use. I used a discarded 62 inch satellite dish and used CD's to create this along with materials that I had laying around. Nothing was purchased for this project.
Step 1: Making the Base/stand
I did not have the base, so I made one from 3" ABS plastic pipe inserted in the ground about 18". I then filled it with concrete and re-rod for stability.
Step 2: Attaching CD's
I used a combination of 1/8" X 3/4" fender washers and #4 by 3/8" machine screws for most of the CD's and a tube of leftover silicone adhesive to attach the outer 2 rows. If you have a fiberglass dish, you would simply use the silicone adhesive for all. The CD's were procured from a high school. They were obsolete. The pre-recorded read only discs seem to last longer and produce slightly more reflectivity than recordable discs.
Step 3: Making the Cooker
This unit did not come with the receiver. I estimated the focal point using the existing supports for the original receiver. All the parts were things I had in the garage. I also happen to have a welder. Depending on what type of cooker you decide to use will dictate the type of support you should fabricate. I used a 10 x12 wire cooker but you can use anything you have. It must swivel though.
You adjust the distance from the focal point to change temperature and to allow use of different cooking vessels.
Step 4: Aiming Device
Using the original dish adjuster is perfect for aligning the dish. I believe that this is a 24 volt DC adjuster. I only had a 12 volt battery available. It works but is slower.
Step 5: Getting the Alignment With the Sun
I used a sheet of paper under the dish at the point where it swivels. There is a round opening in the center of the dish. When the sun makes a nice circle in the center you are real close. The final aim is based on observing where the reflection of sun hits the cooker itself. Do not tighten the bolts that allow the dish to swivel on the base. You will use this for following east to west. The electric tilt adjuster is used to fine tune the position of the dish in relation to elevation of sun
Step 6: Testing the Temperature
These pictures show a temperature of 400 degrees. This is adequate for my uses. In an earlier experiment I had CD's covering every available square inch of the surface of the dish. It produced over 800 degrees. More that I needed for cooking. Do not try to retrieve anything from the focal area without a leather glove on. If that didn't come to mind right away then you maybe shouldn't try this.
First Prize in the
Earthjustice United States of Efficiency Contest