Monday, November 17, 2008


Relate to brief and specifications

This was my brief:
My client is Doctor Tony House. He needs a garden light to light up some poacita in his Coromandel home. I have made myself the stakeholder. The light must be self-powered and be able to charge all day and then automatically turn on at night. Because it is in the Coromandel it needs to be rustproof so materials such as stainless steel, plastic, aluminium, brass and copper might be good. The light must also be weatherproof / waterproof. The cost must not exceed $30 and the light can be no taller than 500mm.

My light is self-powered because it has solar panels to charge its rechargeable batteries. It is able to charge all day, with the solar panels, and it switches on at night because it has an LDR (light dependant transistor) which can tell if it is dark or light.

I have used only rustproof materials – plastic and aluminium – so that it will not suffer salt damage in the Coromandel. It is also very heavy because of how big it is and all the rivets in it. It will not be blown over by wind. But it is not weatherproof. Because of the pieces not fitting together and having to use self-taping screws there are large gaps in the shell of the lantern. If I had used a wood mould for vacuum forming I probably wouldn’t have this problem. But as it is the light does not meet this specification.

It also does not meet the 500mm height specification. Because of the vacuum forming machine not fully sealing the moulds in the bottom bulb I had to cut off a lot of the edge on the Gerbel to make it even all the way around. Because of this the two pieces do not sit perfectly together so that I had to add a lot of strips around it to bridge the gap between them. This added considerably to the height and took it over the 500mm limit. The light does not meet this specification either.

My budget was $30. I spent $4 on the circuit board, $10 on LED’s, $1.50 on batteries, $0.50 on heat shrink, $2 on aluminium, $1.50 on the solar panels, $5 on the rivets, $0.50 on wood, $2 on Styrofoam, $1 on screws and $3 on acrylic. I would have been just over budget, $31, but I had to spend almost double this on vacuum form plastic, taking me way over budget. I couldn’t stick with my original design or build the light I wanted if I didn’t have this plastic.

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