Parabolic Solar Cooker - 600mm and 900mm Size

Description

I made this two models of parabolic solar cookers, one with 600mm diameter and one with 900mm diameter.

However I only could properly test only the one with 600mm diameter, since I'm currently in the city were I work and don't have a space to properly do so.

Model  600mm

This model have a focal point at 600mm aprox. from the center.

I have test this model during the end of winter in argentina. The results were:

Parts List

Start by buying the non printable parts, since this can change which parts you would need to print later.

Assembly guide

Step 1

After printing all the parts, assemble the eight blades by putting together the radius A, radius B, base and circumference. Each one has a number in each join to help assembly:

Follow as bellow

Step 2

Trace in a paper sheet the inside contour of the blade, like shown bellow.

Trace an extra 3~4mm around the contour, like shown bellow.

Now cut the sheet.

Depending of the thickness of the paper, you may want to use to sheets of papers glued together for each blade.

Step 3

Trace the paper sheet over the tin foil, cut it and glue together. You can leave some margin to be able to fold the tin foil around the paper sheet.

Keep in mind that the tin foil can have a side that is less reflective than the other. We want to keep the more reflective one.

Follow as bellow:

You can leave some margin to be able to fold the tin foil around the paper sheet.

Step 4

Assemble the blade by dividing the plastic frame in to parts and inserting the aluminum-lined sheet, as shown below.

Repeat Steps 1 to 6 for the eight blades.

Step 5

Add tin foil to the center part. You need to leave uncover the edges of the part, as shown bellow.

Step 6

To assemble the tripod, cur three 350 mm long tubes from the 20mm Rigid PVC Pipe. Add a 45º angle cut to one end.

Pick up the tripod printable parts and the two nuts and screws

Add the nuts to the center of the knobs

Punt together the tripod part with the hinge, using one knob and a screw

Now put together the hinge with the center part, using the other knob and screw.

now add the tubes:

For transport of the parabolic reflector, you can keep all the parts in the current state (after completing steps 1 to 5 for the eight blades and step 6 for the tripod).

Step 7

To assemble the blades and the center, push the base of the blade into the one of the eight side of the octogonal center, as shown bellow:

After adding all eight blades, add the caps in the eight corners. The caps have numbers to help inserting them in the correct orientation.

View of complete assembly

Model  900mm

This model have a focal point at 750mm aprox. from the center.

I haven't properly tested this model because currently I lack a place to do so. This means that, although it does concentrate sunlight, I do't have a proper idea of how much of an improvement is over the 600mm model.

Parts List

Start by buying the non printable parts, since this can change which parts you would need to print later.

Assembly guide

Step 1

After printing all the parts, start by assembly the radiuses.

Radius type A have an A in the joints to facilitate to facilitate the identification of the parts. Put together as shown below:

Radius type B also have an B in the joints to facilitate to facilitate the identification of the parts. Put together as shown below:

Follow by assembling the circumferences. This ones have a C in the joints:

Now pick up the base and ad it to the set:

Step 2

Assemble this parts to form a blade frame. Each part have a number to identify each joint. Follow as bellow:

Make sure to push all the way for each joint

Make sure to push all the way for each joint

Step 3

Now, take the foam and trace the internal contour of the blade, as shown bellow:

Now trace an extra 4~5mm around the foam and cut it out.

Cut the corners.

Step 4

Now use foam cut to trace the tin foil. Pay attention, since one side of the foil is usually brighter than the other. We want the brighter one.

After tracing, you can leave an extra 4~5mm, to make easy to wrap the foam sheet.

Apply glue to stick the tin foil to the foam sheet. Wrap the execs tin foil around the foam

Depending in the wide of the foil you have, you may have to ad a small corner, like this:

Step 5

Add paper tape in the edges of the aluminum-lined sheet. This is to facilitate the insertion of the sheet in the plastic frame.

Step 6

To insert the to insert the aluminum-lined sheet, divide the plastic blade in to, as shown bellow

Now, insert the sheet in one half frame at a time.

Repeat Steps 1 to 6 for the eight blades.

Step 7

Add tin foil to the center part. You need to leave uncover the edges of the part, as shown bellow.

Make sure to leave the edges uncovered:

Step 8

To assemble the tripod, cur three 450 mm long tubes from the 20mm Rigid PVC Pipe. Add a 45º angle cut to one end.

Pick up the tripod printable parts and the two nuts and screws:

Add the nuts to the center of the knobs

Punt together the tripod part with the hinge, using one knob and a screw

Now put together the hinge with the center part, using the other knob and screw.

now add the tubes:

For transport of the parabolic reflector, you can keep all the parts in the current state (after completing steps 1 to 7 for the eight blades and step 8 for the tripod).

Step 9

To assemble the blades and the center, push the base of the blade into the one of the eight side of the octogonal center, as shown bellow:

After adding all eight blades, add the caps in the eight corners. The caps have numbers to help inserting them in the correct orientation.

View of complete assembly

Stand

For the stand, I made this contraption from the pictures from 3 sticks and 2mm thick wire.

The wire is first form using the bellow parts (printed in PLA) by wrapping it around the legs.

The legs are detachable to help separate the wrapped wire from the plastic parts.

Alternatively, you can use a tall stick and wire to suspend a kettle from the handle, or make a stand une using rocks (if available).