I’m not sure where to start researching into this for my A-level product design coursework, but this board has been so friendly and helpful to me in the past, so I’ll start here.
I am designing a high-volume production collapsible solar cooker, for use in the third world. I have all almost all the product designed to a tea, except the actual reflective surfaces.
The “petals” which fold out to create the parabola (shape which focuses all incoming rays of sunshine into one point above it, where the cooking pan rests) are injection-mouled plastic (material to be decided - something highly impact resistant).
The mirrored surfaces must be parabolic, and as reflective as possible, and not-too-fragile (considering the conditions of the great outdoors). Also, if possible, the mirrored surface must require no adhesive/welding/permant fixing to attatch to the main assembly. So far all of the components I have incorporated into the product snap into place.
Options I have thought of:
Simply spray-paint the plastic parabolic surface with a metallic paint
PROs: Cheap, and one less component in the assembly.
CONs: How environmentally friendly are metal-sprays? The spray (i imagine) will chip-off pretty easily, leaving the user with the problem of buying more spray (which may not be readily available.), or, more likely, discarding the product altogether). Also, I have not seen any applied-finishes that are up to the reflective-quality of a real mirror (which is what I need).
An actual mirror
PROs: Highest reflectivity possible.
CONs: Extremely fragile, surface finish easily marred through use. How are mirrors made in high volumes? Can they be actually made parabolic?
A plastic component
PROs: light, easily and cheaply manufacturable/replacable, wears well. Moulded-in fixings can easily be made to ‘snap’ to the main assembly.
CONs: Can a plastic material that is reflective enough actually be found?
IDEA: Is it possible to copy a mirror’s design, but instead of a glass sheet covering a metal-film, an acrylic sheet is used instead? THe problems I can think of with this solution, is that the acrylic itself will reflect light, and that it won’t be perfectly transparent.
I’ve given you a quick brainstorm of the ideas in my head at the moment. Please could you give me some feedback on these ideas, and give me a clue as to which one is the most viable? Also, any new ideas that I have overlooked would be most appreciated!
Also, it would be great if anyone could point me in the direction of any and all information on the manufacture of reflective surfaces! thank you all[/b]