This was one of those parts I was hoping to get my hands on an original, but after exhausting my supply of contacts in the aircraft industry, decided I would have to make it. I have to admit it was not going to be one of the easiest bits to make, but I needed it placement on my nearly finished dome, so I could get on and mould it.
The first problem I solved quite by chance. The main body of this is a 60mm ball, so while looking for plastic balls, I came across a 60mm glass sphere with a laser engraved thing in the middle, so thought that would do. It was a perfect sphere, and just the right size.
The first job was to make a mould of it, so it was sat on a spacer then sat in an old plastic container, and silicon poured in. This was left to cure overnight, then in the morning the whole thing was removed, and polyurethane resin poured in. Once the resin had cured, a perfect resin sphere was ready to start work on.
With the main body sorted, I set about making the light end as it would have been on the proper one. This I had downloaded the plans from the R2 builders web site, so had all the info I needed to make it.
A rod of resin was made with a hole running through it to save wasting resin, then it was lathed to shape and size. The tricky bit as always is the angled sides, which are done by hand, as I donít own any fancy CNC lathes or equipment. As I have said before, I am not found of people that make what I class as hobby stuff via CNC lathes. They input a diagram into a computer then press a button and it does the rest. It produces a perfect part, which they claim to have made, when really a computer made it, and all they done was push a few buttons. No skill needed there.
So anyway back to the bit at hand. With the sides turned and the base turned down to the size of a large drill bit I had, it was all done except for the ridges on the side. I am still working on fitting those, not to sure how to go about it as yet.
So now the light nozzle whatever you want to call it bit was done, I drilled out the round ball section to take it. I this would allow perfect alignment of the centre hole, which I am planning on fitting a tiny home made projector to. I recently came across some really bright LEDís in Hong Kong. I am not sure what MCD standards for, but these are 55,000 mcds each, and by linking four together they can happily run off 12volts. The beam is brighter and whiter than my super duper halogen torch, and they generate no heat. My plan is to print off a transparency to project against a wall. Not sure what to have yet, but plenty of time to decide later. As that was the plan, having this as a working item was a must.
With a bit of filler to join the two bits together smoothly, that part for now is done.
It was now time to make the two rings that hold and also allow the bit to move. After contemplating several ways of making it, I decided the most accurate would be to make the ring round the actual bit, therefore guaranteeing a perfect fit.
First off the holo projector bit was sat on the bench, then using a cut out plastic ring, it was positioned at the correct halfway height.
Then a layer of gelcoat was applied, to give a nice smooth first layer, then several layer of fibreglass tissue were built up forming the main body. This was then left for a few hours to cure.
Then it was removed from the holo projector and smoothed and sanded by hand into shape, repeatedly being held against the main bit to make sure it was ok.
So with one ring done, and perfected so it fitted and allowed movement of the main section, a mould was made, and a second one cast to be modified for the front ring.
This has recesses in each corner so to speak to allow the projector bit to swivel around the full extent. I donít know if other folk have there projector to move via electronics, but mine will be moveable, only by hand.
With the front ring sanded to shape, the two were put together round the main part, and any adjustments that needed to allow movement, but with enough resistance that it stayed where you put it.
With all the main body work done on it, and it would no longer have to go in the lather chuck, it was placed back in the ball mould and resin poured through the centre hole to cast the bottom round section on. To start with as you can see I had it flat base so it went in the chuck, but the bottom needs to be rounded to pivot well.
I also had to make an adjustment to the front ring, as I had the first one two thin, but that only took a short while.
I originally made the end nozzle section as I couldnít source the proper part, but my grooved bits were always a fraction wider than they should have been. However more recently I managed to get my hands on a proper aeroplane light end piece, so reworked the new proper piece onto the end of my main body.
The end result does look much better, but not always obtainable at the time of making. However when making bits like this patients is paramount.
So once finished the body was remoulded and a cast taken in resin. Another bit for R6
Next I set about making the lens for the holoprojector. My first attempt was to cast one in clear resin, but that didn't come out to well, and also takes ages to go tack free. Also it tended to distort an image if shone through it, and as I wanted to project something from the holoprojector, it would do.
So I did the same as I did for the radar eye lens. I made a template so I could heat up some clear plastic in the oven, and then press the top template over the bottom one, giving me a nicely curved lens. A sort of non vacuum, vac formed plastic eye bit. Its not quite the same very round lens as in the proper plans, but that distorted the image to beyond seeing what it was, which was no good either.