Monday, November 17, 2008


EVALUATION of final product

We started off this project with a field trip. We went to the Corillion, Waitangi Park and Civic Square to look at lights that blend into their surroundings. I wasn’t very inspired by this but I learnt something about the technical side of camouflage. The thing that did inspire my design was some Henry Moore sculptures that I found when I was researching ideas for my light and neon coloured lights. One thing that remained throughout the process was the coloured light.

The first few ideas I sketched with these inspirations in mind were kind of boxy and square, which looking back would have been a lot easier to build. But the design I settled on was four spheres on top of each other with a spike on the bottom to make sure it wouldn’t blow away. It was going to have a different coloured light in each bulb (reflecting my love for the neon design) and be clouded plastic. It was to shine all sorts of colours on the poacita. I had no idea in the beginning how I would create it, just that I liked the design.
We researched non-corroding materials and poacita grass. I liked the brass, copper and aluminium but I thought that if I used these metals I’d use all metal or none at all, as I didn’t like the plastic and metals together. So, considering my design, I went with none at all. Having decided that, I had to research plastics as well.

When I drew my design on Freehand I decided that I would have three bulbs, rather than four, to make it easier for myself and to make sure it wasn’t too tall for the brief. I drew up the design on Solidworks. After doing this and talking to Terry about it I realised that I had nowhere for my circuit to go, so I added a base at the bottom. This was going to be made out of white plastic so that the circuit couldn’t be seen. I then started my mock-up. I used corrugated cardboard for the bulbs and flexible cardboard for the discs between them.

Finally I started my design. The first change I made was to swap the coloured lights for coloured discs. The discs were to be made out of coloured acrylic, in pink, blue and yellow. This was my first job – to cut out the five discs on the CAM2 machine. The first mistake I made was to drill out the holes for the rivets and screws straight away, without having even created the pieces that were to attach to them. These caused many problems later; I had to make a new disc on the CAM2 machine and often drill out new holes. This means I have useless holes in the design that just added to its non-waterproof state. This is definitely something I would be very careful of if I did it again.

I then got to the stage where I had to make brackets. I was offered the opportunity to use Polymorph to create these. This was good as it fit with my No Aluminium rule. I designed jewel shaped brackets. Eventually we abandoned the Polymorph because, even after rolling out with a rolling pin, it was still lumpy and we would have cut them out on the CAM2 machine anyway. So I decided to use coloured acrylic and cut them out. These first caused problems because the CAM2 wouldn’t go over the engraved part, so we had to do them in two goes. The second problem they created was when I tried to drill them out they snapped. I broke three this way, and had to make more. So if I did this again I would stay away from the Polymorph and be very careful with my brackets.

To make the moulds for my vacuum forming I used two different materials – wood and Styrofoam.
Where the wood was smooth and even the Styrofoam was lumpy and irregular. Also the wood lave was much quicker to use than filing down the Styrofoam by hand. I lot of time (including after school) was spent filing these. I did have a slight problem with the wood lave in that I didn’t know for sure which tool to use and so ended up making a few scratches in it. But that was quite easy to fix. I would definitely use wood for all my moulds if I had a repeat.

Next I had to use all my moulds. Quite a few pieces of vacuum forming plastic were wasted because I cut them too big or too small. Eventually I got it right and moulded half of my Styrofoam moulds at a time. The plastic on the biggest bulb halves didn’t quite reach the bottom so in order to have relatively smooth sides I had to gerbil quite a lot off the edges of both. Which was a problem when I came to put it all together. When cleaning these I came across a way to have them frosted, like my original plan. When using thinner and a paper towel to clean off the excess polystyrene the paper left a residue on the plastic that made it look clouded.

After all the vacuum-formed pieces were ready I started assembling the shell. I made vacuum forming plastic (VFP, I’ll call it) strips to attach the bulbs to each other and riveted them on to their respective bulb halves. Then I started to form the base and this is where I encountered my biggest problem. Because I had had to take off so much of the two halves of the bottom bulb they no longer fit together exactly. There was a large gap. In order to fit the parts together I had to fit strip after strip in side each other, until I had four strips in total and the base was a lot larger than I planned. This meant that the design became much bigger than the specifications stated it could be and it took a very long time. I couldn’t frost the strips so later when I put the wires in they were much more visible than I’d planned. Also because I used Polystyrene for the bottom bulb the piece was uneven and didn’t fit correctly, even after four strips, so we had to use self-taping screws. Using the screws was a good idea, and it saved me time, but it meant that the design was very far from waterproof, as it was meant to be. If I hadn’t had this huge gap I would have spent time fixing the other small gaps, but with this it just seemed pointless.

Next thing I had to do was to start assembling the base, so I needed my brackets to be ready. I had to bend the edges so I used the Thermoplastic Heat Bender. To take them out, put in the vice and bend them before they cooled down was too much for me so I needed help. A few were snapped/squashed during this but I had expected this and made quite a few more, so I had extras. Next I started to try to rivet them onto the base but the rivet gun would not fit and quite a few more were snapped this way. Eventually I decided that they just would not work. Even if they did, they would leave another large gap. So I decided to make aluminium brackets and stick the jewels – minus their flap bits – on top. The aluminium brackets weren’t hard. I measured, cut and bent them quickly. When it came time to attach them I found I could move them, rivet them, and then bend and twist them back into shape. This was something I couldn’t do with the plastic brackets. Then I attached the plastic brackets on the outside, along with a strip of white acrylic, and not even one cracked as I thought they might. In hindsight I would have done the aluminium brackets in the first place and saved myself a lot of time. Now the base was almost done.

Because of time constraints I needed help with making my circuits. Once these were done I had to put them into my circuit. I thought it would be very fiddly to put these through the holes that were made for them. The only small problems were that one more hole needed to be drilled and the wires needed to be extended. Neither took long. I would probably take more exact measurements of the wires if I did it again. Once these were in the only things left were to rivet up the pieces, which went smoothly, glue down the solar panels, also fine, and attach the base. The base was easy enough except that the holes didn’t match up on the bottom disc and the brackets. As I said in the beginning this was often a problem and we just drilled new holes.

I am really happy with my final product, even if it didn’t meet the specifications and barely met the time limit. Though many, many things went wrong it still looks good in the end so I’m pleased. If I did it again I’d definitely take more care to meet the specifications. Now I know to stay away from the Polymorph, not be too hasty when deciding where to drill out my holes, and be very careful when drilling through small pieces. I also won’t let what I really want to build get in the way of meeting the brief. But even though I didn’t meet the specifications or the brief I did stay true to my original design and I was encouraged to do this by my teacher. Despite all this I still love my lantern.

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