DIY kit lighting - a question / need help

I think I'm ready to start adding a little bit more to my kits, particularly head and tail lights and am toying with ideas on using a seperate circuit for the dash and console with fiber optic. Obviously I'd need LEDs for the head and tail lights and I SOMEWHAT know how to build a circuit.

So far I am using 10 LEDs (2 super white 5mm, 2 3mm super white, 2 3mm UV and 4 red 3mm) for the main lighting and I know what resistors I'll use with the 9V battery. However, I have absolutely no clue where to get all the materials from one spot or (and I'm no above paying someone to build it for me) getting a custom kit from somewhere.

I'd also need help with the fober optic dash. I'm thinking that it would be several strands (like 12, but powered by 3 LEDs (white, red, and green).

Is it possible to runthe fiber cables off the the head and tail light LEDs indirectly (like sort of back feed the light so that you didnt see the FO strands and hot glue them to the back of the physical LED so they only got very little light) and then have a seperate green 1.8mm LED to power the 3-4 green fiber cables?

I dunno... it's an idea. I'm not an engineer by any means... and if anyone has a simple way to do ANY of this or schematics they'd be willing to share... that would be super...

I'm not sure what you mean by 'uv'...
i would use one white led for the dash/console and color each strand of fiber optics.
There are companys in the hobby led lighting business though mostly serving RC and model RR hobbiests. look up RAM.
I did a bunch of research last year when i was looking for Fog lamps for an RC buggy, though i'm not sure i still have my links.

Thanks so much. RAM has EXACTLY what I'm looking for... great tip.

The biggest issue you will run into, is the space to hold everything.

Ive played around w/ lighting models in the past, and the actual lighting & wiring isnt that difficult. Its routing everything, and finding the space for it, that is the biggest issue.

Im currently working on a 1/24 Italeri Western Star Constellation tractor w/ a 48' reefer trailer, that Im thinking about lighting up.

Ive always really liked the look of the 18 wheeler's you see on the road that are all lit up w/ lights all over the tractor & the trailer. So Im currently trying to decide if I want to do it. Im looking at using what are called Surface Mount LED's. The biggest problem w/ these, is their size. They are roughly 2.5mm long, 1.5mm long, and about .75mm thick, so they are extremely small, and tough to work w/. But I can get a roll of 100 of 'em on ebay for about 7 dollars, so thankfully they arent very expensive. Im considering spacing them about every 2-3 scale feet on the trailer, so that could be as many as 48 of these things on each side of hte trailer, plus the lights on the cab.

As far as fiber optics, I dont think you'd want to glue them directly to the LED, otherwise they are going to be extremely bright, since the fibers will transmit all of the light from the LED. Your best bet would be to find a way of putting something between the LED & the FO, to help difuse the amount of light "visible" to the FO strands. As for routing the strands, I'd suggest making them look like they are part of the wiring in the car. That way you wouldnt have to hide them, or hide them in plain sight as it were.

Routing thew wires so they don't peek out into visible areas I dont' think will be all that hard. I do intend on cutting the doors so they open, but leave the trunk closed so that I can put the 9V in there, so I figure I'll route the wires under the cabin. IF I find this to be too much of a challenge then I'll skip the lights on this particular kit and try it on something different.

Hi all,

being an electronic design engineer, I have played quite a bit with LEDs, and I really believe the best answer in model lighting is with sub-miniature LEDs. Look at the SOT23 format, these tiny parts are designed for surface mount on a pcb, so they are very tiny and can thus easily be placed right behind the part to light up (dash, headlight / taillight, side markers, etc).

Try to use the low current models, as they consume about 1-2mA instead of 10mA for the low cost standard models. Good for battery life!

Also, you can find multicolor models now, they come in a somewhat larger size due to the number of connections required, but should still be installed behind a dasg directly.

Although the fiber looks like a good solution, on a 1/24 model routing them is a pain because their minimal radius is quite big, so I don't think it is a viable solution (although it sure looks sexy and may save some power as less leds are necessary - but look for low-power models,see above)

Also, why use a 9v battery? These are pretty expensive and do not hold a lot of current, and since a LED is current-driven you don't get the best battery life with a 9v batt, especially if you use resistors to lower the voltage (resistors consume power to lower the voltage: U2/R). I would use two AAA batt in series, then a much lower resistor (less power wasted). The best way to control a led is to use a current generator, but this would require a little electronic between the batt and the leds, and I think with the 2,4v generator and resistors you are good enough for the application. Try to use one resistor per led, this is because each led chip has a unique u/i curve, so when using a voltage source (all leds have the same voltage applied) you will get slightly different currents in each led. This will result in light differences among identical leds on your models, not very good (light emitted by a led is proportional to the current going through it, not the voltage).

I hope this helps, I am myself very interested in trying to light up a model sometime (if only I had time!)

MM,

Wow man thanks. I can't say I completely understand everything you've said as my electronic engineering knowledge is both dated and hazy. However, I do greatly appreciate the input and I'll make a point to look into that solution. I'm still waiting on my model to show up from Japan so I have a few days to investigate your suggestion, if not for this model then the next.

Of course I would gladly welcome schematics of your idea here so that I could better understand them (and let's be honest here - use it).

In any event, I greatly appreciate the input. Thanks.

why not try cellphone LEDs instead of the regular LEDs you can buy in hardware/electronics shops? i'm currently working again (yes, after a year and a half) on a widebody lanevo VIII that i put cellphone LEDs on for the headlamps. and it makes for a smaller package that you can store better on the car.

oh wait...this uses resistors and a 9V battery, i hid the resistors in the space between the floorpan and tub, and put the battery in the are after the front seats and through the trunk (i opened the trunk for that purpose). sorry i can't recall what resistors i used since the tub and floorpan's glued really solid, but your electronics shop should be able to help you out on this (like what happened in my case).

good luck on this build, hope to see it soon :)