So from the rough cast block of resin, the first job is to square it up. Until you have a squared off block nothing you do will be symmetrical. Once squared off, the work can being, and the first job, is the slight angling of the sides.The next job was to mark out the detail on the top, and machine down the centre leaving a recessed channel, and two little indents either side. When done this is where the knob and buttons will go.
  While not the hardest part to make, the thermal detonator as it is called was perhaps the most enjoyable.  It started out as a block of tooling resin, which is very easy to mill and lathe, but when sanded with very fine wet and dry sandpaper come sup very smooth and shiny, prefect for mould making.
Up until this point I had been using biker message board posted pictures to shape and add the detail, but when I done some frame by frame watching of ROTJ DVD, I noticed the indents to either side, were not central as many had them, but offset to one side. So out came the filler, and replacements were added in the right place this time.To get a nice overall smooth look, the sharp corners were sanded and rounded off by hand till it felt right.
With all the making done, it was time to mould it. As this was not a straight forward shape the mould needed to be in four parts. The main body, the two ends and the base.To make it the main section and two ends were bolted together, and then gelcoat and fibreglass matting applied for strength. At the same time as applying the gelcoat to the main section a couple of coats were added to the base plate, and also a piece of matting to reinforce it. Finally when both halves were set, a layer of gelcoat was painted on the adjoining flange, and the two halve stuck together to form a box. Most thermal detonators are hollow, again this is because ABS is hard to join well, or without leaving join lines or glue marks. However I wanted mine to be a proper sealed unit, not just a hollow box.I also made the buttons and knob from scratch so they were just the right size.
The grey hose sections were a rod of resin turned to size, then recesses taken out for rubber 'O' rings to be placed at intervals along it. It was then heated and bent to a slight angle, then a mould made and cast taken in coloured resin. The end caps were also turned from resin, then moulded and cast.The base plate had a recess made in it, so the belt buckle would fit nicely inside it, so not only looking neat, but nothing to dig in your back when wearing it. There is also two Alice clips to be fixed to each side, to hold it upright when in place, and to avoid that nasty droopy thermal detonator syndrome you see far too often.You will also see the finished imitation section of cable tie, which as I said before was just to finish it off. As they say attention to detail is everything when making stuff like this.
A few pictures of the finished box section.  The buttons and knob have been added for effect, leaving just the cable tie part to be added later.  the film used one used a section of hoover hose running through it, held in place with a cable tie, but as my hose was solid and glued in place there was not need for the cable tie, but to keep it as close to the film one as possible a section was made and cast to simulate the tie in place.