Author Archives: ndholmes

True Red-Yellow-Green Signal Repeaters

I’ve always liked the idea of fascia signal repeaters, just so operators on through trains don’t need to push to push their way into every corner just to see those inevitable awkwardly-placed signals. Is it prototypical? Probably not, although in either cab signal territory or now as we’re pushing into the new world of PTC, it’s not that far off. It just makes for a smoother operating session, in my opinion.

One option is 3 LEDs per signal head – one for each major color. That’s a lot of LEDs to make room for on the panels. Another option would be red/green bi-color LEDs, energizing both to get a mixed fake yellow color. That has the advantage of one hole per signal head, but the problem is there’s often significant variation from one LED to the next (requiring tuning the color of each individually), and they have a strong color shift based on viewing angle. What I really wanted was a true three-element LED, with true red, amber, and green emitters. The problem is that most of the very few true red-yellow-green LEDs are surface mount, which doesn’t lead itself to being installed in fascia panels.

There is one option, though – the Lumex SSL-LX5097SISGSYC. It’s a standard 5mm LED, albeit with four leads, and available off the shelf from Newark. The red and yellow are reasonably bright, but the green element is a bit weak. Still, some experimentation on the bench showed that they were more than bright enough for panel indicators, and with the proper resistors could be nicely evened out to the eye. At 5V, putting 1k on the red lead, 560 ohms on yellow, and 220 ohms on green provided subjectively even indication brightness.

Since I didn’t want to solder resistors and leads on to something like 60 LEDs, I built a small PCB that integrated a place to mount the LED, the three dropping resistors, and a small JST SH-type 1.0mm 4 position connector. Panelized into groups of 7, it cost me $30 to have 210 individual boards made at PCBWay. After that, it was a matter of getting a solder stencil, slathering on paste, placing components, and then reflowing them in my toaster oven that’s dedicated to PCB manufacture. For those interested in making their own, the schematic, PCB, and Gerber files are all under the “ckt-sigcon” files in the ISE CKT-SIGNAL project on Github.

Three ckt-sigcon panels assembled and ready to go on the bench.

Once assembled, it was a simple matter of soldering in the LEDs and installing them in some of the new control panels that we’ve been 3D printing. Connections to the little LED boards can then be made with 4-wire cables available from a number of sources. I have a large supply, since Iowa Scaled Engineering uses them for connecting to our newest versions of the TrainSpotter detectors. However, Sparkfun also sells them for their Qwiic I2C network system, and I’m sure you can find more sources. Ours are custom made by DirtyPCBs.

Two signal repeater LEDs installed in the back of one of the panels. I was experimenting as to which side I wanted the LED mounted on, hence why the two boards are on upside down. I settled on the upper configuration – with the parts toward the panel – being the preferred orientation.

The end result is a very nice looking signal repeater panel with very clear indications in both normal room lighting and in “night” mode.

The signal repeater panel for the Kuskulana intermediates, which will be located at the south end of the bridge.

Leaving Cordova in 1913

Here’s an interesting old photo I picked up last week – a CRNW train leaving the Cordova depot. For those who don’t know, the Cordova depot was located at the bottom of the hill on the south end of First Street. Hand-written notes on the back of the image indicate this is August 8, 1913.

Leaving Cordova on Friday, August 8, 1913

There’s a couple interesting items in this photo. The first and most obvious is the fact the fourth car back from the engine appears to be a house. Zooming in, it appears that the CRNW is moving some sort of structure north on a depressed-center flatcar, and notes on the back call it a “house”.

Other interesting bits are the two GATX tank cars immediately behind the engine, which were used to deliver fuel oil to Kennecott. I wish I could see the number on the rear car, but at least this confirms the CRNW tank cars were GATX. Then behind the house on the flat are six of the 20t Western air dump cars loaded with what appears to be gravel. My guess is that this is gravel from the pit on the north side of the Odiak Slough and the yard being moved up the line for filling trestles and shoring up the early track.

Also of interest is the Cordova station sign. It shows “TO WHARF 1.3 MI”, which makes perfect sense given that the wharf is the end of track. However, on the other side, it shows “TO CHITINA 129.4 MI”. It’s interesting in that this shows the railroad, at least when it was painting this sign, still viewed Chitina as a junction between the railroad’s main line (Cordova to Chitina, with future expansion northward) and a branch over to Kennecott.

Here’s a closeup of the front of the consist:

New Control Panels

Now that the fascia is all there, it’s time to start mounting control panels. This is one of those things I’ve been agonizing about for some time. My traditional method involves printed track diagrams sandwiched between two pieces of acrylic and bolted into the fascia. I’ve never liked it, because inevitably the acrylic gets scratched or cracks, the print on the paper fades or the paper yellows, and they’re just a pain the butt to actually build because of all the cutting and drilling that must be done precisely.

Michael came up with a novel idea when I was visiting ISE World Headquarters a few weeks back. Basically the whole thing is 3D printed, and the track and lettering is printed using a different filament color. We don’t have a Prusa i3 with the multi-material upgrade yet (it apparently shipped today), so filament changes are currently handled manually. However, the holes are just made as part of manufacturing, and since the track and lettering is literally molded into the panel as part of the print process, it’s almost indestructable.

Here’s the Chokosna lumber reload spur panel…

Right now, we’re printing them using white and “glint grey” PLA on a textured Prusa bed to give it a finished texture. The indicator LEDs (amber for turnout position, white for timelocks, other colors to come…) are 3mm pre-wired LEDs I found on Amazon.

Five Years Ago

My phone and Google reminded me this week that five years ago, I was up in CR&NW country at Kennecott. Alternately seems like ages ago and yesterday all at the same time.

The preserved McCarthy station building, now the local museum.

Fascia Completed!

This thing is actually starting to look like a proper layout rather than just a bunch of track on 3/4″ plywood cookie cutter. At 22:30 Friday night, I joined the upper deck fascia. The lower deck took just a bit longer – 14:00 on Saturday afternoon – because I needed to wait on some brackets to print. With that, the layout fascia is complete and I can move on to cleaning up the room, finishing electrical, and starting to shape in the terrain.

Let There Be Light!

As long-time readers (or others who know me) know, I have a bit of a fascination with layout lighting and making it part of the overall operating day experience. Plus, it’s easier to work on a layout – either from a construction, detailing, or operations standpoint – when there’s excellent lighting. So in today’s post, we’re going to look at what I settled on for lighting the Copper River.

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Attaching Fascia

Since 2020 is officially the year of not leaving the house, I’ve actually made some progress on the CR&NW. More of my time has gone to other projects, like resurrecting a 1940s searchlight signal in my back yard, but the layout is moving forward.

A dual mount point fascia bracket showing how it works

One thing that’s never been quite clear to me is how folks attach fascia board to open grid benchwork in a secure way, such that it’s solid enough to support the weight of an operator who stumbles, yet there’s enough room behind it for the mounting of controls and some modest wiring. If you just screw it straight into the front of the grid, it’s solid but there’s no room for switches and wiring. If you mount it on some standoff wooden blocks, there’s room behind, but has a lot of flex to it. Plus that’s a lot of standoff blocks to cut.

Then I realized I have a 3D printer and this seems like an excellent way to solve the problem – printed standoff brackets.

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Powering the Layout

In addition to track power, which is something most of us have provided by our DC throttles or DCC systems, most of us have a ton of accessories. That can be as basic as things like switch machines or a hodge-podge of building lights, animated features, signals, sound modules, etc. Nearly every single one of those is going to have its own requirements in terms of voltages, currents, etc. Most layouts I’ve ever been on solve this by a maze of power strips, wall warts, battery packs, and old DC power packs repurposed once the owner converted to DCC. It’s a mess.

As an electrical engineer, some things about how people build layouts bug me far more than they should. Messy, disorganized power systems are definitely at the top of the list. I thought I’d give you a look at how power is distributed around my layout to run everything that’s not the track.

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Mainline Completed – Only 2475 Days Later…

So I sketched out the first track plan for my modern day CR&NW on July 31, 2013. On Sunday evening, May 10, 2020 at about 7:45pm, I finished the very last section of main track, connecting the engine facilities and lower yard at Cordova with the outgoing mainline to Eyak and points northeast.

That sounds like an awful progress rate, and it is, but in there I’ve also started a successful side company, managed many of the technical aspects of a $5B merger between two huge global companies (one of which is my day job), dealt with my father’s passing with all the associated estate work and helping my mother to be on her own, and remodeled my entire house. So my personal life hasn’t exactly been slow either.

Fortunately, unlike many of my co-workers, I’m a natural hermit and this “stay at home” stuff has been tremendous for my personal productivity. Not only have I completed the mainline and all of the Cordova yard/dock facilities, but I’ve installed lighting on about half the lower deck and a third of the upper deck, started installing upper fascia, and am now starting to get all the switch machines installed.

That’s not to say all trackwork is done. I have some work left to go on the yard tracks at Chitina and I need to install the enginehouse track at McCarthy. But that’s all pretty minor. It’s just that it’s waiting on a few more turnouts to show up, given the current scarcity of Atlas #7 rights.

In honor of the main line being completed, here’s a shot from my collection of the real CR&NW’s main line back in the early days of the railroad. My guess on era would be 1916-1920 based on other photos in the same group. As to location? Somwhere between Miles Glacier and (probably) Tiekel.

The Miles Glacier Bridge

One of the photos I’ve recently acquired is this view of a train approaching the Miles Glacier bridge from the east. It would appear to be a work train that’s returning from carrying ballast, given it consists entirely of the railroad’s Western side-dump gravel cars and a spreader on the back just ahead of the caboose.

Another thing to note is the trestle wye at the east end of the bridge. Most people don’t realize there was a wye here, completely up on trestlework. I also find it interesting that I can’t see the Miles Glacier station at the west end of the bridge, but it may be just out of the photographer’s field view.

What appears to be a ballast train – given all the side-dump cars and the spreader just ahead of the caboose – heads toward Cordova on the east approach to the Miles Glacier Bridge.