I have finally found the perfect solution for the MLEV’s interior ceiling lighting. I have thought of it before but the ones I was looking for were too large. Luckily, the Pandemic had d forced a many people to stay in their homes. So, a lot of people had to resort to using Zoom and other video conferencing innovations. This gave rise to new and more economical lighting solutions.
Originally, the idea was to create an array of LED lights and a transparent patterned cover/grate to cover them. Alas, there was no PE set that does this and so, it would be too costly. The backup plan was to look for a shallow bowl, coat it with silver and bounce the LED lights off of it. But again, that means a lot of wiring and customised (and even fragile) soldering.
Enter the selfie light…
OK, so the ceiling lights have arrived. It is nothing new as my original idea was to solder a disc of LEDs which creates a circle of spots. Then again, although this looked good, it might be distracting. This 5W light consumes about 740mA and I would need to reduce that. It does get hot after a few minutes even with the heat-sinking aluminum doubling as the circuit board.
The size of the MLEV’s Circle is 120mm and the closest on the market was this 110mm (or 4.7 inch) selfie light which runs off USB, I was slightly disappointed when I realised the dimmable feature on this model did not exist. OK, it does exist but you’re only allowed to choose between full dimming (OFF) or full brightness (ON).
Anyway, after taking a look at the aluminum circuit board, I decided not to tamper with the 5x 4.7 ohms SMD resistors. The Aluminum circuit board is a real SOB when it comes to de-soldering since the metal quickly absorbs the heat from my 30watt soldering iron. Furthermore, the space is so tight, which runs the risk of melting the wires and plastic unless I remove the board but I do not have this whitish glue which is used to bond the whole thing to the plastic.
I used an external PWM LED controller to get the brightness I wanted. This was a PWM module which I bought so long ago but never go the chance to use it. Also, this solution is much quicker than me sitting down writing codes for microcontroller. Not only that, I would also have to design a PCB for it too. There are Pros and Cons but this is just for my model.
This small little 1.0cm x 1.8cm board accepts voltages from 2.8DCV to 6DCV and controls the current from 30mA to 1.5A. Oh, at the back of this board, there is a solder pad which I guess is for you to spread some heat transfer paste and then mate it with a heatsink.
There are two configurations but I am using this version to control the Selfie light via the adjustable resistor.
Looking up at the ceiling from this angle, I am reminded of the unique lighting on the bridge of the NCC-1701D (from the TV Series, Star Trek: The Next Generation). The selfie’s diffuser gave a bright but soft light effect.
It might need some modifications and re-positioning but the Selfie light looks good.
After dimming the Selfie light, this is how it looked. I can go brighter but worry that this will wash out other panel lights and make them not noticeable. But after more modifications and weathering, I might change the setting a little.
The diffused light make the whole bridge look as if there is a natural skylight. If the floor was not blue but maybe satin beige, I might have gone with spotlights.
Here is the comparison of the selfie light’s effect on the Bridge. On the left is when I plugged it directly to a 5v source. It is bright and really does behave like a selfie light. On the right is after I passed it through the PWM module. To me, it does look better and the crew does not need to wear sunglasses all the time.
Just for fun, this is how it might look at night. I took this shot in my car before I drove off after some soldering time at Area88.
With the PWM module on, the current running through is about 160mA compared to 740mA with just the selfie lights alone.
Yes, after a few minutes, without the PWM module, the bright selfie light was worryingly hot at the resistors area. Imagine if you’re streaming for 30 minutes!
Now it the time for me to tie up a lot of loose ends. From the picture above, you can see that I was soldering things as I go along. This was because of the rush to get it ready for a model show. But now, it is time to make it look neater and more organised. I do not want to get the wires snagged on model kit parts or come loose whenever I hold it up for imaginary play to show it to friends. I’ve been putting this off for years but if I do not do this now, when?
Short of some heatshrinks, I can call this done. The repaired Wires now concentrate on one point where I can easily troubleshoot. And that one point is just a simple stripboard cut to size to fit into one of the backwalls.
This stripboard is just a simple power rail for me to distribute the power from the USB power bank. I can add an additional 6 more points before using the top three strip. So, I will have to reserve them as my plan has more or less changed. Each of the other backwalls have space which I can utilise because I would need to add some timed strobes and other sequences. Note that this stripboard serves as a power distribution channel and all the current limiting resisstors are actually at the LED’s ends.
After much thinking, I am considering not to use the Model’s three-legged landing assembly.
