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Discussion Starter · #1 · (Edited)
DIY Lighting: ala' Cylon Raider

This is gonna be a ground up look at what's involved with lighting a model using the Revell 30th Ann. Raider as an example.

From blacking out the interior, to mounting the lights, creating lightboxes and baffles, selecting a power supply, running wires, soldering, heat shrinking and everything in between.

Note that this is the cheap and sloppy way to do it. I am no expert in any of this. I'm just not rich enough to afford lighting kits, so am learning all this as I go.


Total costs expected:
1 can of black spray paint= $1.
up to 7 leds at .10¢ ea = .70¢
up to 7 resistors at .01¢ea. = .07¢
Power supply from yard sale = $1
Heat shrink at $1/yd = ~.01¢
Solder at $1/tube - ~.01¢
Scrap piece of card stock and styrene = .10¢
~6" of fiber optic at $30/100' = ~.15¢
Subtotal = ~$3.04 so far.

We'll round up and call it under $5 for all costs apart from the kit.

An Overview:
Black spray paint the kit's insides kills ambient glow and helps fight light leak. If you want light to bounce around inside, spray with silver or gloss white next. Some will use foil tape as well.

Analyze where the leds are going, how many and how you are going to power them -ext. or int. battery or wall wart. Figure out how you want to connect the juice to the model. In this case, I am creating several access ports for a wall wart as I want the option to film this from several angles.


Coming up: Doing the power supply numbers and resistoring those leds.
 

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Discussion Starter · #2 · (Edited)
Choosing a power supply, whether battery or wall wart, with enough juice to fire your lights is mandatory.

v (volts) is the amount of energy to fire an led.
mA (milliamps) is the draw needed to feed the led.
Circuit is the whole sh'bang (sp?).

Figure out the led requiring the highest voltage needed to fire. This is the minimum v rating your ps can have. So, a mix of 2, 3 and 4v leds means you need a 4v power supply.

Total the mA rating from all your leds, round up however much you feel like and add 10-20%. This is the minimum mA your ps can have. A higher mA is simply wasted. So 10 leds at 25mA = 250mA. A 500mA power supply means you can add ~10 more leds or simply call the balance a waste. There is no penalty for a higher mA rating than is required for your circuit (that I know of).


Reading resistors and frying leds. Oh yeah!
Resistors add resistance to the current flow, lowering the amount of v to the led. If your power supply is 4v and your led is 2v, you need to drop that 4v in half or the led will instantly fry. If the power supply v is just above the led v, the led will die sooner than it needs to. If the ps v is lower than the led v, then the led will live longer than normal -or not fire at all depending on how low the v is.

Resistors have several color bands on them. Reading these will tell you the resistor rating in ohms. What's an ohm? It's a rating like mA and v. Like farads for capacitors, it's not really important what exactly the term itself means, it's the associated number that's important in this case. Resistor charts can be found on the net easily enough. I actually misread the chart in the following video, but the result is the same -it's a good choice I made for the led.

There are formulae to say which resistor is exactly appropriate to the led and power supply you choose. However, there are circumstances where you want to overdrive or underpower your led (Brighter/dimmer). In this case, the formula is just a guide. I don't know the formula, so I just start with too much resistance and back down to a bright level I like. Then, I let the led run for several hours or even overnight. If it's still working when I check back, then I know all is cool. If it died, then I wasted .10¢. If I paid $5 for that led, I would be sad.

Note that in the video I read the resistor rating WRONG. Brown is 1, orange is 1000. I do brown x brown x orange. It should be brown sequential brown x orange. So it's 11x 1000=11,000 rather than 1 x 1 x1000= 1000.



Coming up: Soldering and heat shrinking
 

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Discussion Starter · #4 · (Edited)
Wait no longer!

Solder on.
Note that I am still sloppy at this. In reality, you need the slightest dab to make the solder connection. Whereas I tend to blob all over. It comes down to aesthetics. The main idea is that you apply heat to one side of the wires and touch the solder momentarily to the far side. The heat and the melting will draw the solder into the twists of wire and freeze it all in place. Blobbing it around means you get more solder on your gun than on the wires and what gets on the wires is a blobby inconsistent mess and can interfere with a good connection! No finesse. Either way, it usually gets the job done.

Shrinkage
You can certainly use electrical tape instead of heat shrink, but either way, you must seal your connections for longevity and for killing any cross talk which will short circuit your assembly and likely burn out some or all of your leds. Bad juju. Heat shrink will also stiffen the connections, making them more stable.

First light
So, the wires I cut were far too long. Not a prob, Bob. It's just a matter of trimming them down. I like to have too much up front for unexpected problems, then trim down. It beats having to add wire later. The fewer the connections, the better. What was it Scotty said about over-engineering the plumbing in Trek III?

Keep your scraps. However small they may be, they will likely be useful down the road for another project.

Coming up: Fiber Optics.
 

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Discussion Starter · #5 ·
In this one, I hook up two strands of fiber to the led. Heat shrink is typical, but as there are so few strands, I use some regular electrical tape to hold them to the led. I then seal it w/ white glue and once that was dry, dabbed some CA liberally dosed with baking soda, to encrust the assembly so it can never slip free.

Here's some non-fiber lighting notes about the wax paper on the engines to diffuse the light. Towards the end, I pick up on the fiber again using my MPC star destroyer as an example. The very end talks about 'blooming' the fiber.

Before you are ready to seal your model for good, make sure you test your connections! In this case, I pressed on all the wires looking for bad spots. Lo and behold, I found one!

Almost there! (Finally!) Light bounces everywhere. So you need to block it off. A light box is simply anything which boxes around the light, such as seen in a previous episode. In this case, I wrapped the black card around the engines for more of a shroud. That encased most of the light, but I still had leak going on . In that case, I simply sliced pieces of card and glued it in to baffle the light. The fiber optics were picking up some of the blue spill, so I shrouded that in it's own piece of card. And that was that. I may mention it in an upcoming video.


Coming Up: Final checks and Sealing the body!
 

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Discussion Starter · #6 ·
And here is the final installment. A good shake is given to all the wires one last time, ensuring snug fits at all the contact points. Blasting the interior with canned air ensures that there's no fiddle-faddle about to be sealed inside to make an annoying rattle for the rest of its days.

From there, it's glue a little here and there, clamping the body tight, reapplying glue to any loose seams and that's about that.

Of course, the real modeling now occurs with seam-elimination, priming, painting and all that sort of thing. but we all know how to do that easy stuff, right? ( I still suck at getting a good finish myself.)


With a few basic skills, electronics is easy. Mastering those (as I still must), means more complicated work will ensue down the road.

Hope this helps all the DIY'ers out there!
Happy soldering!
 
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