Adding LED's to Athearn Blue Box GP's


malibu43

Active Member
I've been thinking about adding front and back LED's to my blue box locos to make them look nicer when running. As I put some effort into improving the looks, the glowing cab light is becoming harder and harder to tolerate when they're running (which admittedly isn't often).

I was looking at these on ebay: Athearn Blue Box LEDs

Installation looks easier than some other options I've seen and they'll work with my DC locos now and can be adapted later if ever convert to DCC. For $25 (including shipping) I get enough for all for of my powered blue box locos. I may have to experiment on the best way to shield the LED inside the cab to prevent too much glow out the windows, and I'll have to figure out if I want the number boards backlit or shielded as well.

For folks that are more experienced, do you see any issues with going this route? Anything I should watch out for or expect other than what I've listed above?

Thanks.
 
When I installed LEDS into my Proto Alco PA, I painted around the "bulb" of the LED with carbon black acrylic, leaving only the tip (domed end) clear, to shield excess light coming out the sides. I did the same with the surface mount LED's I used to illuminate the low mounted number boards, leaving only the face to emit light. The other way, is to slip a piece of black shrink tubing over the LED, and position it so the end of the LED is shielded i.e. cut it flush with the tip. LED's project light forward, like a flashlight, so shielding should eliminate most extraneous light.
 
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For folks that are more experienced, do you see any issues with going this route? Anything I should watch out for or expect other than what I've listed above?
I file the LEDs face flat and cement them to back of the Athearn lenses. Then I paint the whole thing black on the inside. No light in the cab.
 
Like Toot has said it's make sense to shield the bulb, so light doesn't leak-out. I buy LEDs in bulk packages of 10 for a little over $10.00. I then buy the resistors for just under $7.00 for 200 of them. I solder up the circuits myself and use heat shrink tubing to keep them from shorting out. I purchase square Plastruct tubes that fit over the LEDs, glue this tube in place near the head and back-up lights to hold the LEDs in place. This makes it easy to replace the LED if I ever have to and shields the light from the LED from glowing in the cab of the loco. ModelTrainStuff is a good place to buy the bulk LEDs and Resistors. Just Remember: the Resistor is attached to the Yellow; or, white wires of your Decoder and also to the "FLAG" leg of the LED.
 
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Thanks guys. All good suggestions!

I was planning on using some plastic to shield the light - either a tube to direct it only to the lights, or a shelf just above the windows to keep the LED on just the lights and number boards. I'll probably have to see how the number boards look once the LED is wired in to decide if they look good when illuminated or if they are better off being shielded from the LED.
 
The ones you are looking at on ebay are designed so that the LEDS are independent of the shell, leaving the shell to be able to be removed without disturbing them. I am, at the moment, installing sound into a Proto 2k GP20. It has LEDS already fitted, front and rear, that sit on the chassis, but then have molded plastic light "pipes" to carry the light to the lens', which are attached to the shell and stay with it when removed.

The ebay wiring looms, largely because of the lack of much chassis in the BB Athearns, are attached to brackets, sticking up, which look like they might be the original bulb holders. The maker has obviously, opted to keep the LEDS in the same position, which does make it difficult to achieve the same result as I've outlined, being used on the P2k.
To see that picture on the listing, click the arrow to move to the right of the photos, beneath the main one.
 
The ones you are looking at on ebay are designed so that the LEDS are independent of the shell, leaving the shell to be able to be removed without disturbing them. I am, at the moment, installing sound into a Proto 2k GP20. It has LEDS already fitted, front and rear, that sit on the chassis, but then have molded plastic light "pipes" to carry the light to the lens', which are attached to the shell and stay with it when removed.

The ebay wiring looms, largely because of the lack of much chassis in the BB Athearns, are attached to brackets, sticking up, which look like they might be the original bulb holders. The maker has obviously, opted to keep the LEDS in the same position, which does make it difficult to achieve the same result as I've outlined, being used on the P2k.
To see that picture on the listing, click the arrow to move to the right of the photos, beneath the main one.

I think I follow what you're saying - picture 6 of 7 shows LEDs placed using the stock bulb position.

However, picture 7 of 7 shows the LEDs mounted to shell (which would allow mounting the LEDs in tubes attached to the shell as previously discussed) with plenty of wire to allow the LEDs freedom to be mounted and manipulated away from the chasis.

I'm not sure I see an issue with the product I linked... but maybe I'm misunderstanding.
 
As this product is giving you 2 alternatives and not having a decoder involved, then using LEDS fixed to the shell will offer the best method to prevent light bleed. Painting or covering the sides of the LED will stop that.
 
Well, I ordered these in February, but finally got around to installing them on 2 of the 4 locos tonight.

Soldering them on was super simple, and I just used electrical tape to cover around the sides of the LEDs, and electrical tape to stick them to the roof of the cab. Results are terrific! Pardon the poor picture quality... and the "layout"... :D

uwR8LeL.jpg
 
Nice and bright. Actually, I wish they had retained the BB models lenses for their method of transferring light. It also lights the number boards too. On the Athearn SD40 from the later model I referred to, and Genesis ones too, they use grain of wheat bulbs for each light on the ends of wires. They also use the domed end of the bulb as the headlight, so there's no lens in place, only a hole. You have to use two lengths of Optic Fiber, poked through the holes, running back to a single LED in the cab, or even further back into the shell, whichever is most convenient and accessible. To light the number boards requires 2 more LED's and some way of mounting them.
 
The picture is of a GP40 that has separate molded pieces for the headlights and number boards, but the number boards still get a little light bleed. The cab gets even less, which was always so goofy looking on the blue box locos.

My much older GP35 has the headlight and number boards molded as one piece. That's the other engine I installed the LEDs on last night, and the number boards really light up. The ones I printed myself a few months ago work very well!

I'll try to get a pic of the lighted number boards...
 
I bought LED bulbs and flashlights in different stores, but each time I was dissatisfied. Maybe I'm too picky, or I just had bad luck with it.
Flashlights have almost nothing in common with model locomotive LED lighting. Do you have a specific scale and model you’re trying to fit LEDs in?
 
when replacing incandescent bulbs with LEDs on a straight DC loco a diode should be added for reverse polarity protection ,
or a bridge rectifier for an 'always on' headlight installation ..
 



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