The box for the lamp is made from 12mm thick MDF. This stuff is cheap, readibly available, can be worked with ease and is perfect for making simple wooden boxes like this. Even for someone with my limited wood working skills. The box is held together with glue with some small panel pins to hold it all in place while the glue is drying. I used the plane to slightly bevel the edges of the wood.
Before painting the box I needed to seal it so the black spray paint I use doesn't soak into the cut edges of the wood. I use lots of coats of the cheapest varnish I can find. This was a reject tin from the local hardware place. I guess they didn't like the putrid green colour! I put on lots of coats then when that is dry sand the box smooth. This particular varnish is water based so I was able to paint it inside without stinking the place out with paint fumes.
The box, once sanded, is sprayed with many coats of black spray paint. I use a semi gloss and try to get a glass like finish. Two wood strips are glued inside the edges of the box for the front panel to screw to. I made the front panel from translucent green plastic. It is easy to work and I am able to make it light up by using a low wattage bulb on the inside of the box. I used a green tinted bulb as a plain 15 watt fridge bulb was too bright. The bulb holders are a tight push fit into the holes which were drilled then opened out using a Dremel.
The dimmer I use is a small circuit I picked up at the local electronics place. It's a very simple triac based design and is good for about 500 watts. That's a lot more than I needed. Everything is mounted to a piece of red plastic bolted to the back of the meter. The meter is a 20mA AC meter so I simply used a 12k 5 watt resistor across the dimmer output with the meter wired in series with it to measure the current. The actual meter reading doesn't really mean anything. It is more an indication of the power level. Of course varying the dimmer makes the meter needle move in relation to the setting.
To turn the lamp on and off I use a mains rated microswitch. It is mounted in such a way that the brass rod will depress the switch when the dial is set to the zero position. When you turn the dial the brass rod moves off the switch lever. By using the switch NC connection I can then have the power turn on when the switch isn't pressed. The vernier dial is attached to the potentiometer shaft with a piece of plastic tube ensuring it is electrically isolated from any mains voltages. I also have an earth wire attached to the metal of the vernier just in case a wire does come adrift inside the box.
Working backwards here, this is the finished lamp. It is very hard to get a good photograph in the dark of it working but this gives some idea. The front panel glows green when the lamp is switched on. The bulb for doing this is inside the box and is wired across the input so the brightness is fixed and not varying with the lamp brightness. Turning the vernier lets you adjust the brightness of the bulbs. I am using standard clear bulbs. These are 150 watt which is far too much to be sensible. I will get some 60 watt bulbs which should be more suitable. I was unable to easily get the long display bulbs used in the original lamps here in NZ. You can vary the brightness from full right down to almost nothing at which point the bulbs give out a very nice, soft orange light. I have been using the lamp for a while now and it works great and is fun to use. The comments from friends have been it looks more like a science experiment than a lamp which is of course just the look I was going for. One friend commented it looks like the kind of thing you'd use to bring Frankenstein's monster to life!
