yard signals (i.e. Switch Markers, Switch Banners)
NW Mailing List
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Sat Jan 28 16:09:03 EST 2023
I have to disagree with Mr. Burnett about the mainline switches being lit. By 1972/73 there were no mailine switches lit, none, nada. And, there were no green or red metal reflectorized markers on mainline switches.Yard tracks did have reflectorized markers on hand thrown switches. Yard track power switches and power derails did have a lighted indicator.Jimmy LisleSent from my Verizon, Samsung Galaxy smartphone
-------- Original message --------From: NW Mailing List <nw-mailing-list at nwhs.org> Date: 1/28/23 12:44 PM (GMT-05:00) To: N&W Mailing List <nw-mailing-list at nwhs.org> Subject: Re: yard signals (i.e. Switch Markers, Switch Banners)
Col. Cochran, Excellency -
Your photo of Crewe Yard is most distressing. Empty. I checked the satellite imagery, and saw the same distressing thing.
The things to which you refer were, in the larger context of American railroading, usually called "switch banners." I worked on the N&W for 15 years and never heard any name assigned to them in conversation, but without doubt the M-W Standard Plans had a nomenclature for them.
Now, a few general principles, as a matter of context: MAIN Track switches were always marked by a light, which was called a Switch Marker. The colors displayed varied from time to time, and from road to road. In the early days, the colors were White and Red. During my time on the N&W, the colors on main track switch markers were Green and Red.
YARD switches... I am not aware whether the N&W had a formal requirement for which switches in a Yard would display a Switch Marker of some kind. Consulting the MW Standard Plans would give you the answer. But I can tell you not all Yard Switches were equipped with a light. The retrospect of 50+ years tells me that ladder tracks in N&W yards always had switch lamps. Switches on lesser-used yard tracks were not marked with a light.
At one time, all switch marker lights (and signal lamps, too) were oil-fired. At some period (1940s, my guess) the N&W began installing, on Main Tracks, switch lamps which were lit with an incandescent lamp. That depended on whether or not AC power was available for interlocking purposes at that location. Before the advent of electric switch lamps, the Section Foreman arranged for the filling of the oil fonts, the trimming of wicks, and the wiping of the glass lenses. At several very large facilities where I worked over the years (non-N&W,) big yards had a man called the Lamp Man, from the MW craft, who cared for the lamps and kept them in good repair. And, to satisfy your curiosity, switch lamps (whether oil or electric) burned 24/7; they were not extinguished during daylight hours.
In my time on the N&W, switch markers used in yards displayed the same colors as switch markers used on main track switches: Red and Green. I seem to recall that, early on, the N&W used different colors on yard switches. Someone with a good collection of early Time Tables can probably find the answer in the Special Instructions. (If there were a change, it was likely made about 1911-1913, when the standard railroad signal colors were changed from White-Green-Red to Gree-Yellow-Red.)
Switch markers used in Yards were almost always fitted with a special type lens called the Spreadlight lens. Its purpose was to diffuse the light over a broad area in the horizontal plane, so that it could be seen from many angles, without having to look at the marker head-on. Spreadlight lenses can be identified by the "ribs" which are cast into the front surface of the lens. Those are actually prisms which orient the light in the desired distribution. It is somewhat counter-intuitive, but orienting the ribs vertically creates a horizontal spread to the light. Sometime conduct an experiment with a Speedlight lens in a darkened room.
As opposed to Spreadlight lenses, lenses for use on Main Track switches, signals, and generally the lenses used in caboose markers, were NOT of the Spreadlight type. Those lenses were designed to focus the light into a beam and project it forward... not to distribute it over a wide plane. Therefore, they have no ribbing on the front surface. As with so many things on the railroad, this was not always the case: a Section Foreman finding a broken glass used whatever he had to repair it, and it worked, regardless of the formal standards. I have also seen caboose markers with Spreadlight lenses stuck in them. "Good enough" was a contrary corollary to "Precision Transportation."
Now to address your immediate question: those little yellow thingies mounted on the "target holders" (yes, that is the proper name) of the switches in your photo. The industry name for these things was "switch banner," although I never heard that term on the N&W.
They were made from stamped sheet steel, probably about 16 gauge. For every one I saw in the 1950s, 1960s and 1970s, the color was always yellow. Generally, there was only one of them on a switch, and the ends were curved outwardly, semi-circularly. When approaching a switch thusly equipped, if the switch were aligned for the reverse (i.e. diverging) route, the yellow switch banner was oriented perpendicular to the track. However, if the switch were lined normally (i.e. not for diverging movement,) one saw no yellow banner perpendicular to the track. A very simple arrangement. Go/No-Go. Or, in that vocabulary we have learned in the digital age, "binary."
Other roads used switch banners of other shapes, and some roads even painted them in different colors. The same situation obtained with semaphores used for Block and/or Interlocking signals: different shaped ends, and different colors, meant different things on different roads. The formal name for such uniquenesses is called Physical Characteristics. If you take a ride down the Virginian, you will probably see things being done in different ways.
Again, time and place are probably your best guides in this case. Things changed over the years; new people came in with different ideas. Eventually, shortly before 1970, as I recall, that garish Scotchlight colored tape junk came around, and the N&W used it to replace illuminated lights on a lot of switches.
Somewhere I have a set of N&W MW Standard Plans which somehow grew feet one night at Goodview, sixty years ago. I will try to find that volume and report back, if it contains anything material to your question(s.)
I hope the above is not too long-winded. But the best answers are always given in terms of context, i.e. the larger picture of how, why and when.
Me...? I am taking the Time Machine back to 1870, and there is a spare seat. Anyone wish to come along?
-- abram burnett
Every Shop Needs a Turnipometer - Order Yours Today !
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