# How I add LED lights to O scale cars



## Dave Sams

I have shown some of my cars on the forum from time to time.

Now, I'm going to show how I did it in detail.

I'm pleased with the results.


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## Dave Sams

I first start with Road Signature 1:43 diecast cars.









Most of them have the headlights applied through holes in the casting.

Look for dark squares in the center of the headlight.


Sometimes, you will find other suitable cars at train shows.










You can see light through the wheel wells.


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## gunrunnerjohn

When I add lights, I typically use liquid tape to coat the rear so that light doesn't shine out anywhere that it shouldn't.

Cars look great, it adds a lot to have lights on them.


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## Dave Sams

Now its time to open up the car. This is where it gets exciting. 
Will the LEDs fit? 
What kind of mods will are needed?


















Looks like the casting is ok, I will probably have to trim out the wheel wells.









But it looks like this may be a good candidate for interior lights.
Gather up the wall warts.








Why?
We all have lots of them which aren't being used. The wire on some is very flexible and perfect for the project.


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## Dave Sams

The Tucker is calling out for interior lights.










A warm white LED and some hot melt glue.










Too bright










A few coats of CSX yellow and we are good.

Yellow LEDs work well too, but I'm out of them.


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## tjcruiser

Simple but great. Really lights up the action!

TJ


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## Dave Sams

The LEDs are in and soldered. I added some Sharpie to the interior LED. It was just too bright.










The hole has been drilled for the wire and inner fenders cut to allow for the LED and glue.










Next, I paint the glue black to keep the light from shining around the wheels. Sometimes the paint runs over the LED and I have to remove it and scrape the paint off. I use liquid electrical tape in other areas. The type I have is thick and I haven't found a good way to appy it in tight spots.

Then its time for final assembly. This is when all women and children must leave the room.


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## gunrunnerjohn

I apply the Liquid Tape to small areas using a toothpick. I just get a little on the end and spread it with the toothpick, allows me to work in tight quarters. I find it's much more effective than most other measures in blocking the light from the back of LED's.


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## Dave Sams

The final product










I'm pleased. On the layout, it will be a very small addition, but I like it. In the wire is the diode and resistor coated with liquid electrical tape.

The LEDs were purchased from e bay. If you look around, you can get them form about a nickel or so. I just ordered 100 yellow for $4.00 shipped. The resistor is 560 ohm and the diode is a small one I bought at Radio Shack. 

I also have packs of diodes and resistors bought off e bay, but they are small and probably made for one LED. The diodes and resistors were bought for $.99 per 100 last year.

When assembling the LED, resistor and diode, be certain all are in series. If the LED won't work, turn the diode around. 

I have 8 cars on my table with lights, and several more to do.

Now I can say, I added 4 new lights to my layout!


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## T-Man

You saved me some time showing me that.:thumbsup:

Thanks!


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## gunrunnerjohn

I suspect the diodes you have will do for at least half a dozen LED's. Remember, the LED consumes at most 20ma, and typically for small stuff, I run them at a lot lower current. I'll bet the diodes are at least 100ma or more rating.


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## Dave Sams

gunrunnerjohn said:


> I apply the Liquid Tape to small areas using a toothpick. I just get a little on the end and spread it with the toothpick, allows me to work in tight quarters. I find it's much more effective than most other measures in blocking the light from the back of LED's.


Haven't tried a tooth pick. 

Dipping the LED didn't work. 

Another thing on my "to do" list.


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## T-Man

I just use black acrylic paint or RTV. The RTV holds it and blocks light. I have learned that the smaller switching diodes work as well and are cheeper. Good point John.


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## gunrunnerjohn

I have a wad of small glass diodes, I looked them up and they're 150ma, so I'd feel pretty safe at using them for at least 100ma.


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## Dave Sams

I use black acrylic paint, but sometimes it runs over the front of the LED.


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## gunrunnerjohn

The reason I like liquid tape is it stays where I put it, and it is totally opaque, even with a single coat.


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## erkenbrand

Thanks for the great write-up, Dave! Now, I have another project on my list of things to do. But you can never have enough lights.


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## Dave Sams

erkenbrand said:


> Thanks for the great write-up, Dave! Now, I have another project on my list of things to do. But you can never have enough lights.


I stopped counting my lights when I hit 200 on my 8x12 table. There are enough lights, I can run without the overhead light on. It looks good.


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