Rust, it was the occurring problem that made me reconsider the elements that I was using. I did want to try my best to make the satellite dish shine. By buying expensive, fine sanding paper. The results were not disappointing, neither extremely great. The labor and work that I put into the polishing would make me think that it would be soon super reflective, but that was not exactly the case. I really wanted to reach the best reflectivity with no complex methods, trying to make it fairly simple, by polishing a metal very well.
Applying the store bought mirrors onto the satellite dish made my work seem a bit useless. But for sure, it wasn't for nothing. I wouldn't come to this conclusion without experiencing this, I believe. I don't think shiny satellite dishes are now a bad idea, that we should not use them. But flat reflective objects, like mirrors, shiny metals, are much easier to obtain. Especially comparing it with the work process needed to make the satellite dish itself reflective. It just takes you to put the flat reflecting surfaces into a right position to make them do the same job as the parabolic dish did.
I will now tell more about the making of my first boiler, Here will the sun concentrate upon, and the water will flow trough it. It was the first time since our school reopened that I spend a Monday morning in the metal workshop, pretty nice! The first two images below depict elements that I could rescue from the trash. Parts from a gas stove and wheel elements. The tubing from the gas stove will be used to make water inlets for the boiler element that I create, the wheel parts will help me to let the satellite dish stand on it's own. I had to sand the parts of the tin cans, they were coated. The residues from the coating were creating smoke on the spotwelding machine, and some sparks. I was pretty happy with the result, but some problems already occurred. The tension between the two slides was too high. The tube has no space left to let water flow through it efficiently. Some tiny holes occurred nearby the areas where the spodwelding has taken place. The connection with the flat surface and the tubing wasn't perfect, rubber elements could improve this. There are some conclusions I make of this first prototype. Using the spodwelder is a great tool, but it makes the connection between the parts temporary, I would like to create a version where I can connect the two plates with nuts and screws. This would make it possible to clean the element, or take out any elements that do not belong there. This would be unpossible with the current model. The travel distance of the water could also be improved, to make sure that it comes into contact with a lot of metal surface. I have looked at plenty of images of heat exchangers, I hope to find some somewhere to have a physical thing to hold. I think that some versions of their shapes are perfect to build a boiler element.
I welded a T-shape to assemble the wheel parts that I found on. Everything looked great, I was happy. But it became a little nightmare to balance the dish after I assembled my shape upon the dish. The wheel elements are too movable, the dish cannot stand on its own without other supports. Reattaching wheels on the found elements would transform this dish into a great driving thing to attach to the back of a bike, to transport materials.
I visited Kazerne! And I did see the nice sun cooker setup. A metal structure, recycled plastic and a beautiful parabolic dish. Id be super happy if I would ever reach the same reflectivity, but I am pretty sure that they used a coating. It was a bit sad to see them exposed in a dark area, putting them outside in the sun would be more fun I believe. What contrasts me with this object is that it's looking like something I could not afford. And that is something I want to avoid to make, what I want to build should be affordable and durable in the term that it's not a creation of waste on a term. (I am not saying that this object is trash, I like it) But water will collect into the dish when it rains ;)
I made a 3D parabolic model and printed it. The idea is that I will paste a tiny reflecting piece of metal on every little block, to create a parabolic mirror setup by flat surfaces. The printed parts will put the metal pieces in the right direction to result into a parabolic shape. I realized this 3D form by drawing a parabolic line into solidworks, I then revolved this parabolic line. I chopped up the shape into pieces and the eventual outcome can be seen in my hand (picture). This direction is developing out of some conclusions that I made with my experience of the satellite dish. A further step is to draw parabolas by hand, I should not need a computer or a printer to do this actually.