Thursday, February 14, 2008

Boiled water

The first step to forcusing is determining where we'l place the mirrors. Since we're talking about inclined mirrors arranged on a flat surface there is bound to be some shading/blocking issues. Here, Djadje moves two mirrors around the wing and draws a rough guide to mirror placement so that we can space the mirrors effectively.


To space the mirrors effectively we--
Wait! Stop everything! Emergency! The teapot is broken! All work ceases and Michel heroically breaks out the oxy-acetylene torch and welds it back together. Phew. OK back to work, nothing to see here.


Using the mirror map we drill holes and place three screws in a broad triangle beneath each mirror. By placing a mirror on the screw-tripod and by varying the height of the screws we can incline the mirror such that it reflects onto the pot. You can see one mirror is on target while another is hitting the building.


Once we have all the screws properly adjusted (it's not enough to do it for one time of day, it has to work all day, so once you do the initial focusing you have to keep it on target for a day or two and observe how the mirrors react to different insolation (INcoming SOLar radiATION) angles and adjust accordingly.) we can proceed to backing the mirrors. I'd settled on styrofoam/glue mix. We bought a large quantity of styrofoam for next to nothing and got to work busting it down.


It wasn't the easiest process:


But it did the trick. The problem was how to weigh down the mirrors so they would stay in contact with the screws. For our first try we makeshifted a fast solution because the glue was drying fast:


Afterwards we reflected and determined that we could glue the mirrors and then tie them down using wire. We found out that wire worked so well we didn't even have to glue them.


That means that we could mount the wing and adjust the mirrors a little bit while we saw how they behaved on the machine. They behaved pretty well! We managed to boil some water, and we're at only half power! I assume we're at around half power, but you never know what ol' bucket-o-rocks is up to.


This bodes well for the final product, but the hardest part is yet to come.

The next step is to build the mold, and then use that mold to stamp out copies of our original. It will not be easy. Again, if anyone has any ideas about how to effectively make a very large mold of these mirrors let me know.

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