Like to change lights on 17 track powered RK switches and throws to LEDs.    Looked at changing track powered to auxiliary but it looked like a ton of wires .       Has anyone done this or is it a little bit nutty  ? 🐿


Original Post

Perhaps you can now buy off-the-shelf LED replacements that fit in the RK lamp holders.  But a few years back I ended up assembling my own LED replacement for the lock-on (sideways facing light):


and the lever controllers (upward facing light).  


I do NOT wish this task on anyone!  Do NOT try this at home! 

Separately.  As for powering turnouts from Accessory power, I'd think this was the more common method (rather than using track voltage)?   Sure, you can't beat the convenience of using track voltage with the screw-terminal jumper...but I wouldn't call the Accessory power method a "ton of wires."  Whether you run an Accessory "Bus" alongside the track picking-off the voltage as needed...or just a few point-to-point wires from transformer-to-switch depends on how many switches you have, if there are other Accessories to be powered, etc..


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Last edited by stan2004

Thank you Stan 

I don't have a pair of needle nose players like your's.   .. . sooo.... I'll need 17 sideways and 34 upwards ........when you get time . 🤡      I think I should take your advice and "do not try this at home ".


I have converted 10 passenger cars and 16 cabooses with GRJ's LED modules and actually considered removing the 17  " green " bulbs at least in the lever controllers and a half dozen lockon bulbs.

I have a 30 inch wide by 72 inch long yard . In the 30 in. width I have 8 rail lines made from 4 entrance 031 sw. and each line split with 072 s.    I then split off  the end  with an 072 for two yard switchers.  Before I added this yard with the switches , I don't remember having  a loss of sound from an RK Allegheny above 26 SMPH like I'm getting now.

This yard seems like it would be the easiest area to use the auxiliary power method on . The main area ( 5' by 16' ) has the switches scattered . 


I run a Lionel Trainmaster 1034 for signal lights , yard lights and some buildings.  Two fixed channels on the TIU with a Z1000 on each set of rails.

Would you use the Z1000 auxiliary ports for the switches or the Trainmaster ?

Thanks again Stan.

If you're presently using track voltage to power your RK switches, that means at any given time each switch is lighting up 2 bulbs (one in the lockon, one (red or green) in the lever controller) with 18V AC.  I'm surprised you haven't had bulb burnouts!  As I recall, I measured something like 1 Watt per bulb at normal Accessory voltage.  It would be more than that if the bulbs are running at 18V AC... at least 1.5 Watts per bulb or 3 Watts per switch.  I'm not sure I got the number of switches in your yard right, but if it's say a dozen switches you're burning 30 Watts just to light them bulbs!  Yikes!

Obviously, those 30 Watts (or whatever it is) steals power from your engine(s).  So a 100W Z-1000 that is dedicating 30 Watts to keep the switch lamps burning only has 70 Watts to power the engines.

In my opinion, you should immediately (that means Do Not Pass Go, Do Not Collect $200) change how you power your switches to Accessory voltage using the 1034 which is presumably set to something closer to 14V.  Now you'll have a full 100 Watts from the Z-1000 to drive your engines.

As an experiment, you could also remove all the switch screw-terminal jumpers (which apply track voltage to the switch).  In other words this removes the switch lamp power from the Z-1000 in your existing configuration.  This is just a test and of course you can manually rotate the lock-on lamp to change switch position if need be for the test.  In any case this would allow the Z-1000 to show its gratitude to you for removing the burden of all those lamps...and I'd think the engines might also start behaving better.

Last edited by stan2004

I'm going to have to sleep on this one Stan.

've never had a bulb burn out .......but when you say  "  YIKES  "  .....well, I better get this figured out soon. 

I'll have to get up in the morning with some kind of remedy.

Thanks again  😨


Nice!  You should see a 5-10x power reduction in going to LEDs.  So now the lamps should draw just a few Watts total. This would be the closest exit.

I'd be interested in seeing a before-after or side-by-side photo of the original bulb and the LED version.  As I recall, the narrow directionality of LEDs required 2 versions (sideways projecting and upwards projecting) to get suitable brightness.

HEY Arnold , 

A really big THANKS..........Ever since I began using these RK switches I have been trying to figure out how to resolve the issue of all these incandescent lights.   I could swear I could smell plastic heating up when I entered the layout  room ( only 16 ' by  20 ' ) after having operated the railroad with all these switches . Stan said... "  YIKES  ".  😨

I was getting ready with the accessory method  that Stan had mentioned .  The method would have been a logistical nightmare 😖 the way I have this non typical layout arranged .

Once again the FORUM continues to be such a great asset to the hobby .     Thanks again.

Stan , if I am able to get the comparison photos posted you'll see them.

Maybe Arnold has a chance now since he has been fortunate enough to install some of them.

I guess a ' new day ' helps to refresh things.   

Stan ,

I ran my linen and Zippo roll between the Allegheny and a consist on the 80 foot line .  I ran that around a dozen times and had no problem after that with sound up to 50 SMPH.

Sometimes I forget the basics !!!  🤔




Hi All... I have sent a couple of photos of the lights. These are great, I have also installed them in my cabooses, they have 3 bulbs in each caboose so I was trying to cut down the amount of power and amps they were using and it DID make a difference, I also installed them in some MTH houses and the Miller beer wagon, and yes no heat. The only issue I have with them is the base of the bulb is more square than the MTH bulb so on some items it is harder to install them. I thought I could just straighten out the wires and reinsert the led bulb into the MTH base but the bulbs are glued into the base. So I ended up just filing back a little of the base each side to make them fit.

Note that the color tint is about 3000K so it's not like the real bright LEDs.

Thanks Arnold


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Thanks for the photos.   Looks suitably bright.  I read the only comment on the T&C site for this product which suggested the brightness was a bit dim in a passenger car application and I didn't know what to make of it.

If one of the LED units ever fails (it won't), I'd be curious if you could "break" it open, scrape away the glue, and photo what's under the hood.  I believe there are 2 teeny-tiny components in addition to the LED and it makes sense that they would use glue as the substrate to keep the components in place.  I guess it was asking too much to simply transfer the components to the existing RK base! 

If the LED push in bulbs aren't bright enough  in the passenger cars you can apply the chrome Mylar material on the entire ceilings .

When I ran out of the Mylar I put a light coat of GOO glue down and applied Reynolds aluminum foil .  It made a big difference when i only had a  small section of the LED strip to work with.   I had the small strip facing up.

LEDs planned for 17 switches and half dozen or so lock ons.

When I  replace the RK bulbs  for LEDs,  I thought that the switches themselves would have improved performance in some manner because of the more a available current..............BUT ........the advice I remember was from most that it was better to use the accessory terminals on the Z1000 for all the switches .

The brick does about 20 volts for the track  ........The accessory terminal output is 14 volts 🤤🤔    Do the switches work better with less voltage ?

The Z1000 is limited to 100 Watts...whether that be from the main track output or the 14V Accessory output.  While it is true that powering the LEDs with 18V consumes more power than 14V, the difference is small compared to the massive power savings in replacing the incandescent bulbs.  Plus, it sounds like re-wiring the switches for Accessory power would be a nightmare.

I could get into the finer points of operating the actual switch machines at the different voltages, but since you've been using the track voltage, why mess with success.  For example, if a switch jams midway thru travel it will consume a huge amount of power and potentially heat up and melt something.  The meltdown will occur much faster at full track voltage than 14V Accessory voltage.  But like they say, trains are NOT meant for unattended operation.


Stan, MTH switches have a resettable fuse installed to protect the coil if the switch should jam. Do you know whether or not they actually work? I never put a switch to the test for fear of burning up the coil.



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Stan ,       manufactured products always need attention.   We are talking about mating plastic with various types of metal and moving parts with variants of temp ,humidity , voltage ,vibration of electrical machines rolling over them , electrical residue , etc.,  all making for an interesting mix.  You have to fine tune these things with files and hammers and an armament of knowledge from the FORUM.

I had a dream last night ........,the 5' by  20 ' layout becoming a 400 ft. continuous loop with 100 non lit lock ons  and some kind of brick arraignment.   Only a half dozen engines to fine tune and a couple of LED lit passenger cars.

Only fun in dreams. 😴


Dave Zucal posted:

Stan, MTH switches have a resettable fuse installed to protect the coil if the switch should jam. Do you know whether or not they actually work? I never put a switch to the test for fear of burning up the coil. 

Good point Dave!  As a matter of habit as soon I hear that tell-tale buzzing sound of a jammed switch I immediately cease-and-desist!  I opened up one of my RK switches and looked up the specs on the resettable fuse (X135 or 1.35A Hold current).  It should trip in about 10 seconds for 14V Accessory voltage, and a few seconds faster for 18V operation.  They work!  


Photo of LED BULB internals 

Comparison of LED and OEM.    OEM ON THE LEFT.

Then comparison  of LED and OEM  with inside top of plastic light housing with Tamiya flat white.  Brighter but not as overwhelming as OEM .  IMO the white iteration looks better on the layout.



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Wow, that was fast!  Great photos.  


So it's a 1-cent resistor and a 1-cent diode.  Apparently the wire-terminals of the components themselves are bent thru the plastic sockets.  These look thicker than the wire terminals of the bulb but I guess are not too thick to impede plugging in the LED version.  It looks like they had to grind off the flange of the LED to make it fit in the plastic holder(?).  There are so-called flange-less LEDs that don't have this lip but are less common and undoubtedly more expensive.

The brightness looks great!  The efficiency (lumens per watt) of these LEDs has improved rapidly.  When they first came available to the consumer/hobbyist I don't think they would have been bright enough for this application.

Kudos for your curiosity to confirm what's under-the-hood. 


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The plastic housing on these bulbs cause only occasional issues with fitment . The MTH lot numbers seem to be the issues . Some of the OEM bulb basses where not easily fit from one switch to another .  There were 3 years from the beginning of switch buying til present of the 17 presently.

The components of the LED bulbs were not glued in , only an interference fit.

The LED was damaged by me . I actually had a small horizontal wire cutter that I used to chew 

the plastic base away.   I soldered the component to the bulb .   I used a Dremel fine point diamond bit to make room in the OEM housing to be able to install the bulb unit.  It now resides in a light socket with the other 59 LEDs in the switches and lockons.    

This has been another interesting project.

Thanks for your curiosity in the LED internals Stan.

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