Three Color LED HO Signal Head

[RR_Mel]

I want to thank Randy for keeping me “on track” looking for the perfect LED for my signals!!!!

 

I have spent months over the last couple of years looking for a good looking three color LED for my HO signals.  I tried dozens of LEDs before I found the prefect one for my signals.  It is a SMYL4-RGY by Bivar.

 

 

 

https://www.bivar.com/Files/Datasheets/SMTL4-RGY.pdf

 

The SMTL4-RGY is available from Mouser, Digikey, Newark & Arrow.  I bought mine from Mouser.

 

It was surprisingly easy to solder the four wires to the LED even as small as it is measuring .110” x .126” x .073”.  The hardest part was managing the #36 Litz wire, it’s so light and flimsily it’s always getting caught up on something.

 

All three colors are perfect!!!!  The yellow is actually a very realistic amber, perfect for RR signals.  The only problem is the LED has a flat surface, no lens.  That was an easy fix, I chopped of the lens of a warm white 3mm LED and glued (AC) it to the SMTL4.  That worked very good with the exception of the depth in the NJI signal head, it was recessed further than I wanted.  Another easy fix, 3mm clear Acrylic rod.  I glued the cut off LED lens to the Acrylic “light pipe” then cut it off with the lens in the position I liked the best.

 

From early on I learned that using black paint to seal up light leaks on LEDs has to be done perfect or the paint will ding the emitted light.  I used a clear Acrylic paint to seal the outside of the LED/lens to prevent the black paint from seeping between the lens and the LED then used black to seal the unwanted light leaks.

 

 

 

 

I used 1000 grit sandpaper to polish the lens and Acrylic light pipe for most light from the LED.

 

 

 

Thanks again Randy, I now have perfect three color HO signal heads.

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

[rrinker]

 Those look like and the part number sounds about right for the ones that Dick Bronson sells at RR-CirKits. Proper RR green and amber. Luckily all my signals are Type G's with 3 individual LEDs so I don;t have to deal with the tiny contacts.

                                              --Randy

 

[RR_Mel]

Actually these were rather easy to work with.  It might be because I just had the cataracts removed from both eyes.  I found them super easy to solder to.  With them glued to the lens/light pipe my Panovise worked very good holding them.  I did them both in the housing and without the housing.  I just gooped the solder tabs with paste and all it took was a quick touch with my iron and the wires were attached.  I have 24 soldered and 16 finished in my signals.

 

I’m making my signals from K&S brass tubing, Oregon brass ladders and Mel castings.  I started out using NJI signal heads but they haven’t been available and I got tired of waiting on them so I made my own heads.

 

 

 

 

 

The three colors are perfect.  I ended up using 2ma for red, 12.5ma for amber and 4ma for green.  That got the brightness as close as I could by eye.

 

 

 

 

 

 

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

 

[j. c.]

nice makes my signals look shabby.

[RR_Mel]

I was having a hard time gluing the tiny 3mm LED lens to the 3mm Acrylic rod so I tried to put a rounded top on the Acrylic rod and it worked.

 

I tried several methods and the one that worked the best and easiest was to cut a small piece of rod and chuck it up in a mini ¼” hex chuck and put that in my 4 volt drill.  The low speed on the drill is 200RPM and holding the Acrylic rod against a 120 grit sanding block and rotating it to slowly round off the tip forming a lens.  The 120 grit sandpaper got it in the ballpark then finishing it using the same process with a 1000 grit sanding block to polish it.

 

 

Much easier than trying to glue the rod centered on the LED lens using AC.  The Mel lens seems a bit brighter than the glued on lens.

 

Much easier as well as faster, less frustrating too!  I find that me and AC don’t get along very well most of the time, I tend to get more on me than the object I’m working on.

 

 

Mel

 

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

[mbinsewi]

That signal looks fantastic Mel!  Wow is all I can say.

Mike.