Cliff: Copper NSD
Cliff says, "A Dalek or two has been on my 'to do' list for years but it wasn't until my youngest daughter started making copper sculptures for her art degree that an idea flashed into my mind: Wouldn't it be great to have a Dalek on permanent display in the garden - but make it out of copper.
The copper was sourced from builder's skips in the shape of airing-cupboard hot water tanks. I just cut off the top and bottom and cut down the long join and it just flops out into a flat sheet. The thickness is remarkably thin, about .5mm, so it's reasonably easy to cut with tin snips.
Looking at the hemispheres, I thought all I needed were 28 copper cold water cistern floats but they're like gold dust second hand and I refused to buy new as it would cost quite a bit. So what I eventually needed was a hemisphere shape that I could 'heat and beat' flat copper into".
How it was done...
A copper cylinder is 18 inches in diameter (46cm), this is the perfect diameter for the top part of the dome. The picture shows the dome with the top outlet soldered over and the water heater thermostat removed. The bottom of the dome is made of three pieces wrapped around, these are bent and ready to solder, this will bring the diameter up to the required 52cm.
The neck strut blocks were cut out of flat copper and folded into a 3-D shape. This also included the small round studs on each block, which was pressed into the flat shape. Once Cliff got into the swing of things, each block took about 10 minutes to make. They were then tacked onto the copper struts in the correct positions.
Having got two neck rings fitted to the uprights, Cliff offered up the dome and some neck blocks for a quick photo. Here, half of the top ring is shaped, just the last two pieces to go then it's time to join them up and fit the final ring. Note that the dome now has its edge chamfer and cowl attached. At this point, it's really starting to look like a Dalek!
Cliff decided to use a fitting from the side of one of the old cylinders to make the dome turn. He soldered in a mount for the male part of the fitting inside the dome. Next, he bent up some supports to take the weight of the dome. On top of these, he then fitted the female threaded half of the fitting. This has quite a substantial thread and easily takes the weight and bulk of the dome.
This is Cliff's take of the gun. To make the bosses he used some threaded collar plumbing parts from where the pipes come out of the water cylinder. Other parts were made from various thicknesses of copper tubing. Being impressively oversize, it has a bit of a 'cartoon' look to it. Cliff is more than happy with it, saying, "the bigger the gun the bigger the bang".
The slats were made by transferring the shape of a template to metal. A jig was made up and the indent was 'pressed in'. Then using a piece of tube over a rounded coach bolt with the metal sandwiched in between, the imitation bolt heads were tapped in. This was more successful (and easier) than trying to make the bolt head indented.