I have been thinking about how to approach the targeting system since the beginning of this build.
There were two options for the 'ball', a clear plastic one and a solid gray plastic one.
I wanted to be able to see into it like the real thing but I don't like working with the clear plastic as its not pliable and cracks easily. What I ended up doing was using the gray one and altering it. Now the targeting system did not include any internal details so I knew I would have to completely scratch build the interior.
A couple of hurdles I came up against were the lenses for the modules and the three glass panels on the front of the ball.
The surface of the panels are light reflective, at the same time being see through. I spent a good deal of time experimenting with different materials and what I discovered was that both of these qualities were found in a pair of cheap sun glasses, which I could also color match for the gold and blue tint.
For the internal lenses I found lots of useful bits and pieces after dismantling an old smart phone, like small lenses.
Once I had these problems sorted out I built up the targeting system up in a few stages.
Stage one: I made a styrene base to fit in the back half of the ball, which I used to add detail to. I added some small parts from a smart phone circuit board including some circular ones to act as the bases for the lenses. The whole thing was then primed and painted a base color of black. I used metallic blue and silver to paint the various details.
Stage two: I used three phone camera lenses for the laser tracker, infrared camera and the F.L.I.R night vision. Once they were glued into position I added some wires.
Stage three: I cut out the three individual panels from the front of the ball. I had to be very careful here not to break the very thin frame. To make the actual panels I used the masks that came with the kit and stuck them to the sun glass lenses, cut around them with clippers and then carefully filed them until they fit snugly into their corresponding holes. I used extra thin cement to secure them into place and then bound the two halves of the ball together.
A fine scriber was used to give the joint better definition.
Final stage: For the bolts around the frame I used a rod of styrene 0.5 mm thick and sliced it as thin as possible, then stuck them on one by one. There are around 80 bolts in total.
The results have surpassed my expectations, and the piece has a great sense of realism. All of the time I spent agonizing over this part of the build has paid off . I can now happily move on with the build.