How to repeat PL's on the facia without breaking the bank

[eric220]

Some of you may remember this cryptic comment in the "Viewing Signals on Layout During Operation" thread, in response to the suggestion that I duplicate all 100+ signal arms on my layout with PL's on the facia.

That will be cost prohibitive, not to mention some logistical issues with mounting. I did think of another option that I've been tossing around. More on that after I have a chance to explore the concept a bit.

Well, it started with this germ of an idea and a conversation with a friend who owns an ABS plastic 3D printer.  Next came this:



The thing is designed to hold five 5mm LED's in alignment through the facia, with a cap in front.  The cap was designed to replicate the look of the cab signals in GG-1 4935.



A little 3D printing later,



Add a trip to Radio Shack and a little rattle can black,



A little assembly and testing later,


(this shot is the most realistic as far as the lit aspect is concerned; the rest of the photos are much more washed out than in person)

Finally, mount on a test platform that can be clamped to the layout to test visibility, and it's ready.



I'm using a selector knob to generate the different aspects.

The results are pretty encouraging.  In practice, these would be driven by the same circuits that power the on-layout PL's, so I just have to buy the LED's, get the 3D printing done, and assemble.  The printer used to make this prototype is not quite FUD resolution, to put it politely.  On the flip side, for the investment of the ABS thread (something to the tune of $25), I can have as many of these as I want.  The savings are significant enough that I think it's worth experimenting to see if I can get better results through reorientation.

[peteski]

Interesting solution Eric.  But I assume that your PL signals on the layout use 9-LED heads.  Why not just design a repeater signal on the fascia which mimics the 9-LED head of the actual signal? Using either 3 or 5mm LEDs?  Wouldn't that simplify the electronic circuit (as both instances of signals would be identical in design (rather than driving a 9-LED and 5-LED signal heads?)  Plus, the fascia version would look more like the signal on the layout, and would be more compact than your current design.

[eric220]

Actually, a pair of 7-lamp PLs (no down-sloping "restricting" aspect) would take up at least as much space, if not more than the 5-lamp cab signal that I designed.  If I was going to go that route, I'd be inclined to use the same heads that I'll use for the layout, since even 3mm LEDs would result in very large arms a-la the old NJI's.  The current plan is to use TrainCat's as-yet-unreleased circuit boards.  It's already an extremely expensive proposition to do all the signals on the layout, and I'm not keen on doubling the cost to repeat the signals on the facia.  There's also the question of visibility for my operators, of whom I am by far the youngest with the best eyesight.  I'm not convinced about the visibility of the scale PL's for all the operators.

The wiring isn't an issue.  Both the Alkem and unreleased TrainCat signals have a single control wire for each pair of lamps around the center, meaning they can be driven from a regular clear/approach/stop signal driver.

[peteski]

Ok I see most of your points. But I don't see how a small 5mm lenses with pinhole sized dots to represent the aspect will have better visibility than a 7-LED 3-mm LED representation of the signal head mounted on the fascia.

[eric220]

Ok I see most of your points. But I don't see how a small 5mm lenses with pinhole sized dots to represent the aspect will have better visibility than a 7-LED 3-mm LED representation of the signal head mounted on the fascia.

That's kind of a cheat.  The signal can be read based on which lamp is lit.  If you see the center lamp lit, it's stop.  If it's the top, it's clear.  If there are two lamps lit, there's a diverging switch thrown.  For the majority of the signals that are right on the aisle, the aspect will reinforce how to read the real PL's on the layout.

[Ed Kapuscinski]

I love that these look like cab signals. I'm digging it.

[kelticsylk]

Absolutely cool. I saved this thread to the reference files under Signals. Hopefully I'll get to use it at some future point.

[MichaelWinicki]

I think it's very cool!

The challenge that I have with it is the number of times during a train's journey that someone is going to have to step back from the fascia, take their eyes off the train, and have to read the signal output on the fascia.

[eric220]

The challenge that I have with it is the number of times during a train's journey that someone is going to have to step back from the fascia, take their eyes off the train, and have to read the signal output on the fascia.

Keep in mind, ultimately these are repeaters. I do plan to put proper PL's on the layout. These just help with visibility.

[Rich_S]

Eric, I've never been on a GG1 and it looks like you have a prototype photo of a GG1 aspect, but I can tell you current aspects contain only 4 indications

• Clear
• Approach Medium
• Approach
• Restricting

The above cab signal aspects are used on type EL cab signal equipment. Similar aspects are used on Ultra Cab 1 and Ultra Cab II equipment. I'm not sure if GG1's used type EH or EL cab signal equipment? I'm also wondering why GG1's would use a different style aspect, unless this was a Amtrak application?

Very nice layout idea, two thumbs up 

[eric220]

Rich- My guess is that the GG-1 used the same system. In the prototype photo above, you can see that the lowest lamp is, in fact, a restricting aspect. As with many things on my layout, I've slightly tweaked things to better suit my application. I have to say, I find it kind of strange that the prototype can't display a "stop" aspect.

Based on the description that starts around 3:40 in this video, they would appear to be exactly as you describe.

[Rich_S]

I have to say, I find it kind of strange that the prototype can't display a "stop" aspect.

Eric, On the prototype there is a rule that states the more restrictive signal indication will apply, when comparing the cab signal indication to the line side signal indication. What the Pennsy did was try to create a repeater type signal for line side signals without covering the cab walls with signal lights. So they ended up using the 4 indications for the 13 possible wayside indications as follows:

Clear = Clear
Approach Medium = Approach Limited, Approach Medium, Limited Clear, Medium Clear (All Medium speed or better indications)
Approach = Medium Approach, Approach, Approach Slow (All Medium speed or below)
Restricting = Stop, Stop & Proceed, Slow Clear, Slow Approach, Restricting (All Slow speed or below)

Hopefully this helps?


 

[TiVoPrince]

Interesting
use of the printing technology.  I wonder if the 'face' could be angled like the prototypes shown in locomotive cabs.  This would allow operators to see only the appropriate signal as they approach a control point and no ability to see the 'opposing' signal.  Happily this product (in either form)  could also be used for repeating 'regular' signals too...

[eric220]

I was having a brainstorm.  Here's what I had in mind as far as signal repeaters on a simple two track crossover.



There's some obvious issues there, and something like a four track crossover (I am planning one of those) exacerbates that problem.  Since I'm already fudging the aspects, and since even the prototype fudges the aspects (approach over stop instead of the reverse for approach medium) I had the thought of flipping the signal on its side.



It's a further departure from the prototype, but it might work better for the application.  This also raises the concern that the "top" of the signal flips based on the direction.  That might cause confusion for the operators.  On the other hand, the reversed directions might help distinguish eastbound signals from westbound signals.  Thoughts?

[Rich_S]

I was having a brainstorm.  Here's what I had in mind as far as signal repeaters on a simple two track crossover.



There's some obvious issues there, and something like a four track crossover (I am planning one of those) exacerbates that problem.  Since I'm already fudging the aspects, and since even the prototype fudges the aspects (approach over stop instead of the reverse for approach medium) I had the thought of flipping the signal on its side.



It's a further departure from the prototype, but it might work better for the application.  This also raises the concern that the "top" of the signal flips based on the direction.  That might cause confusion for the operators.  On the other hand, the reversed directions might help distinguish eastbound signals from westbound signals.  Thoughts?

Even though the vertical aspects take up more space, to me they are easier to read. When you lay them over to a horizontal position, the Approach Medium signal no longer looks like Approach Medium, but now looks like you have two Approach signals and two clear signals.  The only problem, like you mentioned, a four track cross-over is going to take up quite a bit of space.