Science Summer School
I supervised during two public school teacher training projects during our June summer school at OLC. This project involved an OLC student becoming familiar with the science project to be undertaken during summer school. The student then led the class and shared information with local public school teachers enrolled.
We completed 2-day seminars with each of the four groups of teachers, with 5 students in each class. Two of the groups learned how to construct a solar cooker and the other two groups learned basic radio telemetry field techniques and computation methods for determining an animals location from known positions using triangulation.
The purpose of the summer school seminars was to give local public school teachers hands-on experience with new science topics that they could take back to their schools and share with their students.
Solar Cooker Design and Construction
In this seminar students were shown how to construct an award winning solar cooker from common materials, including a galvanized washtub that served as the container for the plywood oven. This cooker was featured in Home Power magazine, Issue #37, and was designed by Jay Campbell.
Here OLC student teacher Valerie Janis looks on as the class marks out their reflectors on a sheet of masonite prior to cutting the pieces on a table saw. From left to right are Dee Ann Deon Brewer, James Mesteth, Francine Janis, Raymond Handboy, and Patricia Hammond.
The chalk line comes in handy for marking cut lines on the plywood that will form the oven box.
Raymond, Dee Ann, Francine, James, and Patricia work together to assemble the oven box.
James cuts the circular top for the oven . . .
. . . and Dee Ann and Patricia attach it to the oven box.
Once the reflectors are hinged together and the aluminum foil glued on, they are ready to be attached to the frame holding the glass that covers the top of the oven.
And the proud class displays their finished solar cooker, ready to bake a meal.
If you are interested in building this cooker for yourself, the list of materials and tools required, as well as detailed instructions are shown below.
Materials List: Tools:
1. One 2 diameter galvanized washtub. 1. Table saw, handy, but not required
2. One 15x15x1/8 pane glass 2. Circular saw
3. One 4x4 foot sheet 1/8 masonite 3. Jig saw, handy, but not required
4. One 4x4 foot sheet 3/8 plywood 4. Measuring tape
5. Ό x 3/4 weatherstripping foam 5. Chalk line
6. Four small metal hinges 6. Clamps
7. 3 strips 2x12 nylon webbing strap 7. Hammer
8. Elmers glue 8. Safety glasses
9. 1 nails, Ύ nails 9. Hearing protectors
10. 8 x 2 velcro 10. Utility knife
11. Aluminum foil
12. 12 #8, ½ x 1/8 machine screws, nuts, and washers
4x4 foot 1/8 masonite sheet cutting template
Three 1 3/8 x 16
Three 1 3/8 x 16
4x4 foot 3/8 plywood sheet cutting template
1. Glue and nail 14 3/8 sides to 14x14 bottom to make oven.
2. Turn upside down on flat surface and place 18x6 pieces around open end of oven box.
3. Pieces wont extend out to make perfect square, there will be a 2 gap at the end of each piece. Glue and clamp in place.
4. Remove oven box and place washtub upside down on frame. Mark around rim of washtub and remove.
5. Nail pieces together using Ύ nails, being careful to leave about 1 space around inside and outside of line so that when sawing out circle you wont cut through any nails.
6. Use jig saw or circular saw to cut out circular top, cutting outside of line Ό to ½ to ensure good overlap of rim of washtub.
7. Apply foam around underside of circular top on marked circular line so that foam will form a seal when top is placed on washtub.
8. Glue around square inside rim of top and nail oven to top, nailing from the inside out so that top of oven box is flush with top of circular frame.
9. Apply foam strip around top of oven, leaving about ½ from opening. Make sure foam forms a continuous single-layer seal around top of oven so that glass frame will lie flat on it.
10.Glue bottom side of 3 1-3/8 x 16 masonite strips and apply to 3 sides of the 18 x 2 square plywood frame, positioning the strips so that the outer edges are flush with the outer edge of the frame. The glass pane will later fit in between the masonite strips with room to spare. Apply glue to the top side of the strips and place the 18 x 1-7/8 square plywood frame over the base and nail frame together using Ύ nails. Keep nails at least ½ away from the inner edge of the opening so as not to interfere with insertion of the glass.
11. Place glass frame on top of circular top of oven and screw on hinges so that frame is evenly positioned over hole.
12. Screw 1 ½ x 14 plywood strip to back of glass frame using 1 drywall screws, placing screws about ½ from the rear edge so that they wont interfere with glass pane.
13. Screw hinges to front edge of strip about 2 in from sides.
14. Lay one side reflector against back reflector, smooth inside surfaces facing each other. Let bottom corner of side reflector extend 3/8 below bottom edge of back reflector (distance is exaggerated in drawing). Glue and staple webbing hinge in middle of joint between two reflectors.
15. Attach other side reflector the same way.
16. Fold side reflectors flat and cut off protruding corner extending below bottom of back reflector with wire cutters. Place bottom edge of back reflector against hinges and mark where holes will go.
17. Drill holes in back reflector and attach to hinges with machine screws, washers, and nuts.
18. Once back and side reflectors fit and fold properly, remove and apply aluminum foil with glue and lay flat with weights to sit over night.
19. Apply aluminum foil with glue to front reflector and tape edges with plastic packing tape.
20. Glue and staple web hinge to back middle of bottom edge of front reflector.
21. Glue and apply web hinge and front reflector to front of glass pane. Put 1 3/8x14 masonite strip into gap where glass will go through frame and staple web hinge to frame using Ό staples (3/8 staples will poke through and stop glass from sliding into place). Remove masonite strip after stapling. (Strip is used so that stapler wont bend or break frame with void underneath where glass enters.)
22. Slide glass pane into frame.
23. Cut the two 2 Velcro strips in half lengthwise and apply two 1 x 4 pieces end to end along the edge of each side reflector. Cut the matching Velcro strips into 1 x 4 strips and apply to the front reflector where the side reflectors will meet it when they are in the open position.