Help replacing headlight in Atlas YB RS-1

[wjstix]

crossthedog

I might keep an eye out for those green boards and if I get a couple of them I could put them in several engines that would make a good mu consist.

Buying a new lightboard from Atlas for $22 wouldn't really make much sense. Since many folks remove the lightboard when they add a decoder (several companies make 'drop-in' decoders that are shaped like the lightboard they're replacing) and toss them, you might be able to pick one up for free. You can buy diodes and resistors online for very little money that will do what you want to do. 

Ho Pc Board Compatible With Rs-1, Ho Master Locomotive Spare Parts, Atlas Model Railroad (atlasrr.com)

[PC101]

Lookin good.

[crossthedog]

Turns out I had some really small drill bits. I cut the second light bar a little shorter and started with a drill bit smaller than the one I use to drill holes in ties for track nails. Then worked my way up to what apparently was a #32, because when I went to see how the hole compared to the LED bulb, this happened...

The fit was perfect. So now I have a bright headlight at both ends.

I know from the discussion above that both lights wouldn't often be on at the same time, but I like it and it works for me, at least until such a time as I feel I have the patience to try to implement more complex lighting. 

Thanks everyone but hats off especially to Tom for the drilling idea.

-Matt

[crossthedog]

tstage

Since your initial pilot hole didn't crack the light pipe, I'm guessing your 1/8" OD drill bit was on the dull side and that's what stressed the hole, which lead to the cracking.

Likely. And as I mentioned, the light bar is thin (vertically) toward the middle of the shell and gets gradually thicker at the lens end. I probably needed to cut the bar closer to the lens, where the drilling surface would be "taller" and there would be more room for the larger hole. I was worried that cutting the bar any closer would make the number boards not get enough light, but I needn't have worried. The light coming out of the number board slots will put your eye out.

-Matt

[tstage]

Matt,

Since your initial pilot hole didn't crack the light pipe, I'm guessing your 1/8" OD drill bit was on the dull side and that's what stressed the hole, which lead to the cracking.

I agree with Dave about drilling a much smaller initial pilot hole then using 2-3 incrementally larger drill bit sizes before drilling the final hole.  Also make sure your final drill bit is sharp.

Another suggestion: Shrink a 1/4" long piece of 1/8" OD black heatshrink around the bulb of your LED.  If the heatshrink is thin, it might allow you to press-fit the LED into the 1/8" hole.  And, if you make the heatshrink a little longer, you can shrink it over the back of the LED, too.

In regards to the #32 drill bit, check your local Ace Hardware.  Mine actually sells # drill bits individually.

FWIW,

Tom

[crossthedog]

hon30critter

You can reduce the amount of breakage by starting with a smaller drill bit, i.e. 1/16" and then enlarging the hole incrementally until you get it to the desired 1/8".

Tom's comment upthread recommended using a #32 drill bit, which works out to like .116 inch, which is between 7/64 and 1/8. I didn't have a #32. I started with the 7/64 but it was when I was widening it with the 1/8 that the plastic broke. I may need to cut the light bar shorter, as it gets thicker the closer you get to the lenses.

hon30critter

The light looks great. I would suggest painting the light tubes if there is light shining out of the bottom of the locomotive.

Thanks, Dave. Capital idea!

[hon30critter]

crossthedog

I cut the long hood light bar, drilled a hole in it, the edges of the hole broke,

Hi Matt,

You can reduce the amount of breakage by starting with a smaller drill bit, i.e. 1/16" and then enlarging the hole incrementally until you get it to the desired 1/8".

The light looks great. I would suggest painting the light tubes if there is light shining out of the bottom of the locomotive.

Cheers!!

Dave

 

[crossthedog]

wjstix

FWIW one of the original purposes of the green 'lightboard' use in engines was to provide what was called 'constant lighting'. The board would be wired so that when track power was applied, the first couple of volts were routed directly to the headlight, and then as you increased power it would get to the motor to move the engine. This meant if you were careful, you could reduce the throttle enough to make the engine stop, but keep a trickle of power in the track to keep the light on.

Yeah, that's the only downside here. In both the videos I posted I had to race my engines around the loop; I almost never run a train that fast unless it's a hot shot or a passenger train, but I had to do that to get the headlight up to full quasar. It would be nice to be able to have the light on bright at low speed or idle. 

I might keep an eye out for those green boards and if I get a couple of them I could put them in several engines that would make a good mu consist.

-Matt

 

 

[wjstix]

crossthedog

 AEP528

I suppose you could design a lighting circuit to provide regulated voltage for the LEDs, and another circuit to prevent the motor from turning until track voltage got above the regulated voltage. That would allow lights to be on while the locomotive is stopped, although the track is still powered.

 

 That would absolutely smash. I love that idea, but I'm not even going to ask you how to do it. 

 FWIW one of the original purposes of the green 'lightboard' use in engines was to provide what was called 'constant lighting'. The board would be wired so that when track power was applied, the first couple of volts were routed directly to the headlight, and then as you increased power it would get to the motor to move the engine. This meant if you were careful, you could reduce the throttle enough to make the engine stop, but keep a trickle of power in the track to keep the light on. (The lightboards were also usually set up to do directional lighting so only one bulb was on at a time, depending on track polarity.) Unfortunately, this did mean that if you had some engines with lightboards and some without, the ones without would start sooner and run a bit faster then those with the lightboards, so it make it harder to run multiple engine consists.

With DCC, you press a button to turn the lights on or off whether running or stopped, so it makes it a lot easier. It's programmed into the decoder in the factory.

[crossthedog]

I thought I'd report on progress. I cut the long hood light bar, drilled a hole in it, the edges of the hole broke, I put an Evans 3mm LED in the hole and taped it so that it would hold together, reinstalled the shortened light bar and loosely wrapped the LED wires around the buss wires, then closed up the hood to test it.

Success! Here's a quick video of the RS-1 with the new headlight:

https://drive.google.com/file/d/1lcdHsMsXXQ0bGkt8iQ75HbSphYb70GWT/

Here' the project so far:

I need to cut and drill the other light bar and wire up the other light, and then I guess solder the wire ends to the buss wires. But it seems to work and it's nice and bright. That's all I wanted.

Thanks everyone for all the help.

-Matt

 

[crossthedog]

AEP528

I suppose you could design a lighting circuit to provide regulated voltage for the LEDs, and another circuit to prevent the motor from turning until track voltage got above the regulated voltage. That would allow lights to be on while the locomotive is stopped, although the track is still powered.

That would absolutely smash. I love that idea, but I'm not even going to ask you how to do it. I'm 61 and losing brain functionality daily, and can barely grasp the idea of resistors. It would take me so long to learn the necessary concepts for doing what you're suggesting that by then they'll be leading me around by leaving trails of M&Ms.

[AEP528]

crossthedog

Thanks for the tip about number board decals.

 

 

wjstix

Since the Atlas engine you have doesn't have a lightboard, both headlights will be on anytime there is power going to the engine (off when stopped) unless you add diodes in the wiring circuit for each light to make them directional.

 

 

Hmm. I don't mind the nondirectionality. But I would love it if the headlight could stay on bright even when the locomotive was running very slowly or stopped. Can this be achieved through diodes? What do diodes look like, and what kind of bait do you use to catch one?

 

EDIT: Actually, it looks like PC101's image upthread shows a couple of them in the center of the green lightboard. They look just like resistors to me.

 

Diodes simply allow current to pass in a single direction only. That's why a single color LED only lights at one polarity.

EDIT to add: A diode does cause voltage drop, so it would be possible to wire diodes in series to reduce the light brightness. Or just use a resistor.

To have the lights on while the locomotive is stopped normally requires a battery.

I suppose you could design a lighting circuit to provide regulated voltage for the LEDs, and another circuit to prevent the motor from turning until track voltage got above the regulated voltage. That would allow lights to be on while the locomotive is stopped, although the track is still powered.

 

[crossthedog]

Thanks for the tip about number board decals.

wjstix

Since the Atlas engine you have doesn't have a lightboard, both headlights will be on anytime there is power going to the engine (off when stopped) unless you add diodes in the wiring circuit for each light to make them directional.

Hmm. I don't mind the nondirectionality. But I would love it if the headlight could stay on bright even when the locomotive was running very slowly or stopped. Can this be achieved through diodes? What do diodes look like, and what kind of bait do you use to catch one?

EDIT: Actually, it looks like PC101's image upthread shows a nesting pair of them in the center of the green lightboard. They look just like resistors to me.

[wjstix]

crossthedog

I noticed that there are no numbers in the number board slots, though, so the light just piles out of those holes when the loco is running. I'll have to put something in there.

A couple of companies make decals of numberboards, check Walthers website.

crossthedog

Ok, well let's talk about directional lighting. I hear a lot about it and a lot of my locos have it, but I'm not sold. Do prototype engines really have their headlight turn off if they go into reverse?

No they don't. The engineer controls which headlight is on or off, bright or dim. I believe when switching like in a yard, the engine has to have both lights on (at least dim?) for safety reasons. 

Since the Atlas engine you have doesn't have a lightboard, both headlights will be on anytime there is power going to the engine (off when stopped) unless you add diodes in the wiring circuit for each light to make them directional. 

 

[AEP528]

crossthedog

Ok, well let's talk about directional lighting. I hear a lot about it and a lot of my locos have it, but I'm not sold. Do prototype engines really have their headlight turn off if they go into reverse? Obviously, if the engineer has swiveled his seat and is looking the other way there is no need to light the track that is now receding behind him, but wouldn't it just be good safe practice to always have the lights on in both directions?

With DC you only have two options: Both headlights always on, or directional.

It's whatever looks best to you while you're running trains.

[wrench567]

 Directional lighting is great for running on the main line but only on the lead locomotive. Many RS locomotives ran long hood forward, but a few of them ran cab forward. Even fewer had dual controls. It wasn't a matter of swiveling a seat around. The engineer would have to crane his neck around to see the brakeman's signals.

   Switching at night the locomotive would be running with either very dim headlight or just the numberboard, step lights, or side ditch lights on. The headlight shining brightly against a cut of cars would reflect so much light to impead the engineer from seeing the ground person. The rotary beacon would also be lit.

       Pete.

[crossthedog]

wjstix

 

hon30critter

The light tubes have sections running to the number boards so, if the tubes are eliminated entirely, separate LEDs will have to be installed for each of the number boards.

 Only if the lightbar got cut right by the headlight. You could just cut the lightbars farther back towards the middle of the engine body and install the LEDs there. Then the light shines in the headlight and the numberboards. In the OP's lower photo, the cut would be in the cab on the side towards the middle part of the engine body. 

 

Right. I actually figured this out all by my little lonesome, and that's where I planned to cut. I noticed that there are no numbers in the number board slots, though, so the light just piles out of those holes when the loco is running. I'll have to put something in there.

But back to PC's recommendations:

PC101

What would be better with the hard wired green board??? 1) diodes for directional lighting are already soldered in place.

Ok, well let's talk about directional lighting. I hear a lot about it and a lot of my locos have it, but I'm not sold. Do prototype engines really have their headlight turn off if they go into reverse? Obviously, if the engineer has swiveled his seat and is looking the other way there is no need to light the track that is now receding behind him, but wouldn't it just be good safe practice to always have the lights on in both directions?

I recognize that a discussion of directionality is a departure from the quote unquote Topic, and I the undersigned, as the OP, being of sound mind, do hereby give my permission for any and all commentors  to enlarge upon this departure without threat of recrimination or censure (by me, anyway). Have at it.

-Matt

Oh, hey I almost forgot:

wjstix

I'd advise using Evan Designs LEDs, you can get them from Walthers or other places. They are pricier than most LEDs, but come pre-wired with resistors and diodes so you can just connect the two wires to track power and the bulb won't burn out - even on a 14V DCC layout.

Stix, it turns out that Evans is the brand I'm using. I put a "warm white 3mm" in my F7. My hobby shop guy carries them and they weren't that expensive. I like them a lot.

[wjstix]

hon30critter

The light tubes have sections running to the number boards so, if the tubes are eliminated entirely, separate LEDs will have to be installed for each of the number boards.

Only if the lightbar got cut right by the headlight. You could just cut the lightbars farther back towards the middle of the engine body and install the LEDs there. Then the light shines in the headlight and the numberboards. In the OP's lower photo, the cut would be in the cab on the side towards the middle part of the engine body. 

[PC101]

crossthedog

 

PC101

The tricky part is soldering wire leads to the copper strips that come from the motor brushes (needs heat sink and needs to be fast at soldering. Do not heat up the brush spring or the little plastic peg that holds the brush in place).

 

 

"Ok. Important safety tip. Thanks Egon." PC, this doesn't sound like something I would venture to do. When it comes to soldering, I'm not that fast and I'm not that good. (Reminds me of a roommate I had that played guitar, and he always said, "I may be slow but I'm not very good.") And this sounds like there could be serious repercussions to a botched operation. I am curious though... what do you see as the advantage to this dangerous mission? The idea of just soldering the bulb wired ends to the copper busses seems really appealing to me. What would be better about the hardwired green board enough to risk it?

 

-Matt

 

Yes, soldering wires to those copper brush straps, if not done correctly, you will heat up the copper strap too much and then the brush springs will lose their expanded tension and relax and not keep their expanded tension on the brush, which will then not keep the brush snugg against the copper commutator pads on the armature shaft.

As with soldering bulb/LED w/resister wire ends to the buss wire that is good and easy. You could even slip the bulb/LED w/resister wire ends between the buss wires and the gray board, so no soldering for that.

What would be better with the hard wired green board???

1) diodes for directional lighting are already soldered in place.

2) bulbs on stiff/solid wires or the the LED w/resister with stiff legs/leds that you want to use would be soldered to the end of the green board and formed/bent to mate up with the clear light rods/tubes.

I am still running ATLAS YB locos. in DC with gray boards and one light bulb and some have with the green PCB board and directional lighting with bulbs and some with a green board with a 8 pin FM DCC ready socket with an 8 pin M plug. After that it went to a DCC decoder w/8 pin M end then to DCC only decoder board then to a DCC decoder board w/sound. I an not sure at this time which ones have bulbs or LEDs. 

In the August 2023 M R magazine, Editor Eric White talks about tinkerers and mad scientists. How true that is.   

  

[crossthedog]

PC101

The tricky part is soldering wire leads to the copper strips that come from the motor brushes (needs heat sink and needs to be fast at soldering. Do not heat up the brush spring or the little plastic peg that holds the brush in place).

"Ok. Important safety tip. Thanks Egon." PC, this doesn't sound like something I would venture to do. When it comes to soldering, I'm not that fast and I'm not that good. (Reminds me of a roommate I had that played guitar, and he always said, "I may be slow but I'm not very good.") And this sounds like there could be serious repercussions to a botched operation. I am curious though... what do you see as the advantage to this dangerous mission? The idea of just soldering the bulb wired ends to the copper busses seems really appealing to me. What would be better about the hardwired green board enough to risk it?

-Matt

[PC101]

Do you guys think since the OP is planning to stay with DC, maybe he could look for these Atlas printed curcuit boards #824-X001 at train shows or maybe hobby shops and get rid of the gray board with it's 'loose wire connections' and do  'hard wire' connections. The tricky part is soldering wire leads to the copper strips that come from the motor brushes (needs heat sink and needs to be fast at soldering. Do not heat up the brush spring or the little plastic peg that holds the brush in place).

The OP would be able to solder LEDs with resistors to the correct PCB's two inner solder pads on each end to get directional lighting. Many of us pulled these PCB's from these engines when converting to DCC.

Just another option maybe.

There are no classifaction lights (body mounted lens) on the YB RS1, just number boards.

  

 

The picture below shows two Atlas RS 1 bodys,

The body in the top of the picture would have the gray board and one light bulb centered on that board to shine both ways at all times.

The body on the bottom would have the green PCB with a light bulb on both ends of the PCB. The clear light tube/runners have been shorten by ATLAS. With the two black diodes in the center of the PCB, ATLAS now gave your engine directional lighting.   

[PC101]

hon30critter

Hi Matt,

 The two copper strips that bend around the grey board supply power to the motor. One of those may be connected directly to the frame with the other one connected to one of the motor brushes (someone can probably confirm this). If you are converting to DCC you will have to re-wire the motor feed. You cannot use a live frame with DCC! If you are not going to convert the locomotive to DCC, then using the prewired LEDs suggested by a previous poster would be the easiest way to go.

 

 

 

Cheers!!

Dave

 

Confirmed, the copper strip that comes up from the bottom of the motor that bends around the motor to lay on the top of the gray board and under the buss wire is not connected directly to the frame, so no live frame here on an ATLAS YB RS1.   

[crossthedog]

wrench567

I cut my light tubes and polished the cut with a fine fingernail file. One LED on each end of the board with a resistor will give you directional lights.

Thanks Pete! Another vote for starting with shortening the light bars and using two LEDs.

-Matt

[wrench567]

  Haven't seen one of those in a long time. 

  When I converted all mine to DCC many moons ago, I cut my light tubes and polished the cut with a fine fingernail file. One LED on each end of the board with a resistor will give you directional lights.

      Pete.

[hon30critter]

Hi Tom,

I have some Testors Clear Cement. I'll give it a try the next time I am installing LEDs. Thanks for bringing me up to speed.

Cheers!!

Dave

[tstage]

crossthedog

tstage If you plan to ditch the light bars and mounting the LEDs directly to the headlight lenses, use a #32 drill bit and drill them by hand with a pin vise. A 3mm LED bulb generally has an OD of 0.113". A #32 drill bit will give you a 0.116" OD hole, which is a press fit for the 3mm LED.

This is also great detailed info, thank you. I'll have to look at the lenses. I didn't know there was enough "length" in them to actually drill a hole into. I thought they were pretty tiny.

You're welcome, Matt.  The headlight lenses I drilled out were on Stewart F-units and fairly thick so the drilled hole worked in that situation.  If the lenses in your locomotive are <1/4", I would go with the tubing idea.  And to secure the tubing inside the shell of your locomotive, I would use a liquid cement for the best bond.

Tom

[tstage]

The Testors Clear Cement will hold just fine to the number boards, Dave.  A thin strip of tape to hold it in place while it cures should do the trick.  Once cured, you could use additional clear cement to reinforce it.

I recommend it over epoxy or CA because I don't like the idea of permanently mounting something that could possibly need replacing.  And if you do need to replace it, you'll damage the part in the process.

The only time I use the Testors inside a hole is when I'm installing a 0603 LED in a brass locomotive headlamp.  The Testors secures it inside the headlamp, as well as insulates the pads on the backside of the LED from shorting to the brass.

For the styrene tubing drilled out with a #32 drill bit, no adhesive is need at all.  The fit of the LED inside the 0.116" OD hole is loose enough to press it in place and tight enough to hold it there.

Tom

[hon30critter]

Hi Matt, Tom and Stix,

The light tubes have sections running to the number boards so, if the tubes are eliminated entirely, separate LEDs will have to be installed for each of the number boards. It is quite doable but it may be more complicated than Matt wants to get into at this stage of his working with LEDs. Having said that, I am a strong advocate for just diving right in! Do the clasification lights too! People will be impressed!

Tom, your suggestion about using Testors clear cement is excellent if you are securing LEDs in holes or tubes. The reason that I suggested using a quick setting epoxy was more related to attaching LEDs to the backs of number boards or classification lights where the LEDs will be just sitting against the back of the lenses. In cases like that, the faster the glue sets, the better because the LEDs have to be held in place by hand while the glue sets. At least, that is the way I have been doing it. Maybe someone has a better idea.

Cheers!!

Dave

[crossthedog]

Wow, thanks guys. Lotsa great info here.

wjstix

You could try one LED, but most I've seen are directional - they are focused towards the end/top of the bulb, so in this situation the brightest light would be shining sideways.

Stix, thanks for this warning and the recommendation. I don't know from diodes, but I already have some LEDs with the resistors embedded. I'll check out the Evans stuff.

hon30critter

You have probably figured most of this out already, but let me explain the wiring as it sits. It is very simple. You can see

Actually, I had not really figured all that out. It seemed like the bulb wires would want to be connecting to the copper buss wires, but the way they were routed and where they ended made me wonder if somehow the gray plate was conductive, even thought it seemed it could not be. In the Atlas F7 the plate was divided into left and right halves and the bulb wires were soldered directly to that. So that's why I was confused here. 

hon30critter

Second, is this locomotive going to be converted to DCC?

Not by me. Someday when I'm pushing up daisies maybe someone will want to rejigger it for DCC, but this is DC for now.

I believe I'll start by cutting off some of the plastic light bars to widen the space where the existing bulb is, and try mounting two LEDs as you and others have suggested. If that doesn't work, I can yard the light bar completely and try mounting them at the lenses.

Stix, I like the tube idea a lot. And Tom, thanks for the photo. That is extremely helpful for me.

 

tstage

If you plan to ditch the light bars and mounting the LEDs directly to the headlight lenses, use a #32 drill bit and drill them by hand with a pin vise. A 3mm LED bulb generally has an OD of 0.113". A #32 drill bit will give you a 0.116" OD hole, which is a press fit for the 3mm LED.

This is also great detailed info, thank you. I'll have to look at the lenses. I didn't know there was enough "length" in them to actually drill a hole into. I thought they were pretty tiny.

Thanks all, when I get my courage up to try this I'll let you know how it works out.

-Matt