Do you think a GANTLET is feasible

[lionelsoni]

I just got the March CTT and saw the unusual layout pictured on page 77, with two sections connected by a 4-track bridge. The layout is intended for use with only one train, which crosses the bridge once on each of the four tracks during each complete circuit; so the bridge tracks are deliberately spaced as close as possible. It looks like a gantlet waiting to happen!

One possibility is a 9-rail gantlet, similar to the 2-track 5-rail gantlet discussed here except that each pair of adjacent tracks would share a running rail, with each track having its own dedicated center rail. This could of course be done with three conventional tracks, suitably spaced, with the center track connected to the transformer so that its outside rails are connected to the outer tracks' center rails and its center rail is connected to their outside rails. The result is 9 rails, alternately connected to the two transformer terminals.

A more extreme version would use only two conventional tracks, in the same way as the 4-rail gantlet that we have discussed. The rails would be again connected alternately to two sides of a circuit; but a relay would be used to swap the connections to the transformer. Control rails on the individual tracks approaching the bridge would latch or release the relay to get the correct polarity for the rails that the train will use. A relay with three sets of form-C contacts would do the job, two to do the reversing and one to provide the latching contact.

[spankybird]

Elliot, If you plan on sharing your video, I have found 15 to 20 seconds is about the limit for downloads. 20 seconds of video can be about 10 mgs.

So do alot of short ones.

tom

[Big_Boy_4005]

QUOTE: Originally posted by Jim Duda

Gentlemen: Seems it's a given The Professor should incorporate one into his Monster layout...c'mon Elliott, it would certainly be an attention getter - and you could document your control scheme and share it with us. Since it will be computer controlled, have the opposing trains wait for one to clear it, then send the other one over it. Are you game? Post the video on the forum for us...pretty cool stuff!

Jim, the only problem is if I did do one of these, it would probably be inside a tunnel where nobody would see it anyway.[;)]

Speaking of video, I have to finish packing trains, as I am off to do a mall show this weekend. One of the things I will be doing with the display is some relay logic train control. The exact kind of thing required to control this track feature. I will take some video, then I have to figure out how to share it.[8D]

[FJ and G]

"dave, the 5 rail is too easy and what is the point. if you can't have some real" F

---------------------------------

I was off the forum yesterday and today I see the 4-rail plan is gathering momentum. I like!

Not easier but then what would be the point? I am actually building the layout as much to learn about electronics and other things as to experiment. That is 99% of the fun!

A very innovative plan the 4 rail is, that really would have made the March CTT Trackplan page, a good plan, an even greater plan (where it crosses the bridge 4 times).

Thanks for the ideas, guys. You are on the ball.

[lionelsoni]

Daniel, it seems that you have each track's center rail powered through a front contact on a relay whose coil is returned to the other track's supply. So, if the track-2 power is off, track 1 can't operate the relay to get voltage on its center rail.

However, even if you switch the relay-coil returns so that each track's relay depends on its own supply for coil and voltage to its center rail, you still have the problem that a train on track 1 with low or zero track voltage, for example, looks to the track-2 relay like a train on track 2. Relay 2 therefore picks up and tries to put track-2 voltage on the track-2 center rail, which is already grounded by the wheels of the train on track 1.

I think you need form-C contacts on each relay, so that the back contact can disconnect the center rail from the other relay before applying voltage to it.

[Jim Duda]

Gentlemen: Seems it's a given The Professor should incorporate one into his Monster layout...c'mon Elliott, it would certainly be an attention getter - and you could document your control scheme and share it with us. Since it will be computer controlled, have the opposing trains wait for one to clear it, then send the other one over it. Are you game? Post the video on the forum for us...pretty cool stuff!

[Big_Boy_4005]

QUOTE: Originally posted by fjerome

ok, i was following this pretty well until big boy made the CTT reference. i grabbed my feb/05 issue up, but can't find anything related to this. am i looking in the wrong place? abnormally dense?

dave, the 5 rail is too easy and what is the point. if you can't have some real overlap, then the situation won't be clear. go with the 4 rail.

March 05, page 77 will clear things up for you.[swg]

[Anonymous]

QUOTE: Originally posted by lionelsoni

Daniel, let me elaborate on your relay scheme: Since the two tracks would almost certainly be powered from separate sources, each relay should also disconnect the rail that it is switching from the other relay coil before connecting it to the supply. Otherwise, any difference in supply voltages could cause both relays to operate at the same time and create a short circuit. Furthermore, each relay coil should be returned individually to the supply for the track that it is powering, or, better, both should be returned to a fixed voltage.

Bob,

I did not address the case where the 2 tracks are powered by different voltages. For this case, the following can be used:

Connect the coil of the 1st relay between track 1 hot and the 1st switched rail. Connect the NO contacts of the 1st relay between the track 2 hot and the 2nd switched rail. Likewise, connect the coil of the the 2nd relay between the track 2 hot and the 2nd switched rail. Connect the NO contacts of the 2nd relay between the track 1 hot and the 1st switched rail. The frog can be isolated to avoid shorts. When a train enters the gantlet, it will ground one of the switched rails through the wheels, activate the relay and power the other switched rail for the pickup rollers.

When one relay is closed, the contacts bypass the coil of the 2nd relay, preventing both from being activated simultaneously.

Daniel Lang

[lionelsoni]

Daniel, let me elaborate on your relay scheme: Since the two tracks would almost certainly be powered from separate sources, each relay should also disconnect the rail that it is switching from the other relay coil before connecting it to the supply. Otherwise, any difference in supply voltages could cause both relays to operate at the same time and create a short circuit. Furthermore, each relay coil should be returned individually to the supply for the track that it is powering, or, better, both should be returned to a fixed voltage.

[fjerome]

ok, i was following this pretty well until big boy made the CTT reference. i grabbed my feb/05 issue up, but can't find anything related to this. am i looking in the wrong place? abnormally dense?

dave, the 5 rail is too easy and what is the point. if you can't have some real overlap, then the situation won't be clear. go with the 4 rail.

[lionelsoni]

I don't think that uniform rail spacing is necessarily unprototypical. As long as the gantlet produces the needed clearance, the rails could be spaced equally. However, one could further obfuscate the dual use of the inner rails by spacing them just a little bit un-uniformly. That is, put each inner rail perhaps 1/8 inch off-center between the rails that flank it. This would create an obvious 1/4-inch difference in the spaces between railheads, which would then be about 7/16 and 11/16 instead of 9/16 each, while keeping the pickup offset tolerable.

[spankybird]

Elliot, I have to agree with you, I believe the 4 rail would be great for Dave to build.

[Big_Boy_4005]

QUOTE: Originally posted by lionelsoni

Actually, the 4-rail version has the same number of rails as a prototype gantlet, while the 6-rail version is the one that reveals the toy-train use of three rails.

There is another give-away with the 4 rail version Bob, but it is rather subtle. The rail spacing is equal on all 4 rails. Of course this is necessary to preserve gauge on both paths. Because of this it requires a full gauge and a half in width to construct.

The 5 rail requires 2 full gauges of width. The only space saving really comes from the clearence that would normally be found between tracks, as it is reduced to nil in this scenario.

If I was going to do this, I would go for the 4 rail version, in spite of it's slightly more complex electrical considerations. Hint, hint Dave.[swg]

[lionelsoni]

Actually, the 4-rail version has the same number of rails as a prototype gantlet, while the 6-rail version is the one that reveals the toy-train use of three rails.

[Big_Boy_4005]

QUOTE: Originally posted by jkerklo

Would a prototype railroad ever share rails like in the 4-rail or 5-rail diagram? Seems sharing rails would cause construction/maintenance problems.

John Kerklo
TCA 94-38455
www.Three-Rail.com

I think the answer is no John. The 4 and 5 rail versions are strictly from the 3 rail toy realm. The 6 rail version represents 2 distinct tracks interlaced, that is most true to the prototype. It is also the most compact, which is really the entire point.

[jkerklo]

Would a prototype railroad ever share rails like in the 4-rail or 5-rail diagram? Seems sharing rails would cause construction/maintenance problems.

John Kerklo
TCA 94-38455
www.Three-Rail.com

[Anonymous]

QUOTE: Originally posted by Big_Boy_4005

Actually, the 5 rail proposal is the simplest. Here's a diagram of what each idea would look like.

I like the 4-rail design. It makes it a bit more challenging! [:D]

What you can do is use 2 relays. Connect the coil of the 1st relay between the track hot and the 1st switched rail. Connect the NO contacts of the 1st relay between the track hot and the 2nd switched rail. Likewise, connect the coil of the the 2nd relay between the track hot and the 2nd switched rail. Connect the NO contacts of the 2nd relay between the track hot and the 1st switched rail. The frog can be isolated to avoid shorts. When a train enters the gantlet, it will ground one of the switched rails through the wheels, activate the relay and power the other switched rail for the pickup rollers.

Daniel Lang

[Buckeye Riveter]

I was working in Gary, Indiana between 1980 to 1985 on the Indiana Toll Road. We were builiding new interchanges and that is when I saw the Gauntlet Bridge over the NS and Chessie (CSX now). I thought it was the strangest thing I had ever seen, but you would see the South Shore Train stop at the signal and then the other train would arrive and cross the bridge. The train wreck was in 1993 after I had moved to Ohio.

While I was working in the REGION, the South Shore Train hit a steel truck at Burns Harbor. What a mess! Also, the Calumet Ave Bridge collapsed killing, I believe 14 workmen.

I was glad to leave for a safer area.

[Big_Boy_4005]

Thanks Buck, this spelling thing has been like a metal splinter, and has stuck with me all afternoon. I suspect that the deeper we dig, the more examples we will find of both spellings referring to the track feature. I was actually surprised to find the spelling without the U in the dictionary on my desk. Indeed, it was only used for railroading.

[Jim Duda]

Gauntlet or Gantlet?...who cares?
It's how the train that runs on it fares.
Whether day or dark night
The squeeze will be tight!
Caveat Pilotor - Let the engineer bewares... (wink)

[Buckeye Riveter]

News Article 1,
January 18, 1993
In the first passenger fatal accident since 1909, Train 7 from Chicago runs a red signal on the western approach to the Gauntlet Bridge, goes into emergency stop, and pauses for 5 to 30 seconds before being hit by Train 12 from South Bend. The lead cars, Car 27 Eastbound and Car 36 Westbound, slice into each other killing 7 passengers in Car 36, including a 10 year old boy. Most of the victims were decapitated. There were initial reports of 70 or 65 injured. (A 1998 TV report claimed 150 injured in a story about a lawsuit, as well as reporting an eighth passenger death from injuries sustained in the crash, but this report is not supported by other media.) A signal prior to the signal run had been reported defective in prior weeks, however the Gauntlet signals were working properly. A second bridge has now been added at the site and the Gauntlet is no longer in operation. The engineer of Train 7 was the dispatcher in the 1985 accident. NO CRIMINAL CHARGES WERE FILED, but both engineers were fired.

Story Article 2
Our next station is a flag stop, Clark Road. We're now in the city of Gary, IN. Just past this station, we come to the Old Gauntlet Bridge. It is so-named because of a fatal head-on crash between two commuter trains that occurred there in 1993. Seven people died. One engineer ran a stop signal, and the two trains collided on the bridge, which takes the South Shore Line over both NS and CSX tracks. The problem here with the gauntlet track was that it was for opposing directions. After the crash, the federal government found some funding to build a second bridge, so that the tracks in each direction could be separated.

Web source 1
http://www.rrb.gov/funfacts3.html

Web source 2
http://www.hyperdictionary.com/dictionary/gantlet

Web source 3
Gantlet track
A gantlet track (in British and Australian English: gauntlet, or gauntleted, track) refers to the situation where tracks converge onto a single roadbed and are interlaced to pass through a narrow passage such as a cut, bridge, or tunnel. A switch frog at each end allows the two tracks to overlap, and the four rails run parallel through the passage on the same crossties (sleepers) and separate again at the other end. Gantlet tracks are commonly used when a rail line's capacity is increased with the addition of an additional track, but cost or other factors prevent the widening of the bridges. Since there are no points or other moving parts in a gantlet track, a train operating on one of the tracks cannot be routed onto the other. Because two trains cannot use the gantlet at the same time, scheduling and block signals must allow for this restriction.
A gantlet track can also be used when two railroads of different gauges share right-of-way; the standard-gauge Delaware, Lackawanna and Western Railroad used the wide-gauge Erie Railroad's tunnel through the New Jersey Palisades in this way before the DL&W built its own tunnel.
The term is derived not from gauntlet meaning a type of glove, but from the expression running the gauntlet, which means running between two confining rows of adversaries.

When I have been around people talking about the crashes described above their pronounciation begins with a gau, which I assume they picked up off of the radio and TV coverage at the time.

A Mud Hen

[Big_Boy_4005]

Fine Steve, I'M WRONG. Are you happy??? It was nice of you to join in the conversation and be so helpful. Frankly, since I don't have one of these track features on my layout, and never will, I run little risk of further embarassment. The word is pronounced the same either way, so as long as I don't write it, nobody in the roundhouse will know how stupid I really am.

[bogaziddy]

From the looks of the picture, that Santa Fe man is headed for the ditch ... Let's hope the engineer has Job Insurance because some overzealous official will hold an investigation and make him run the gauntlet ... or gantlet ... or whatever.

[Anonymous]

Big Boy, I know you hate to admit when you're wrong. But you are in this case.

In Railroad terms, the spelling is GANTLET, and it will remain Gantlet, whether or not you wi***o be correct. You can use gauntlet perfectly fine for the situations that term describes. Many words have similar spellings, but decribe different things. "Sea" and "see," for example.

Railroaders have been known to invent the occasional word, or modify one. Why don't you check out the etymology of the word "caboose" for an example.

If you're going to continue with the improper spelling and pronunciation, you might as well call the locomotive cab the pilot house. Real railroaders might laugh you out of the roundhouse if you use "gauntlet" to describe the track arrangement discussed in this thread.

[Big_Boy_4005]

You're welcome for the diagram Dave (and John K.), I enjoy drawing things like that, to aid discussions like this.

I finally got my copy of CTT, and see where all of this came from.

Sorry about the spelling thing. I see from all of the sources, that either spelling is correct. Personally, I will always spell it with a U, for 2 reasons. First, it tends to make the pronunciation and meaning more obvious, as Spacemouse proved over on the MR forum. Second, from an etymological perspective, the French word predates the existance of trains by hundreds of years.

Truth is, the railroad term is almost part of history. Another hundred years, and no one will remember what a gauntlet track was.[swg]

[FJ and G]

Daniel,

I'm glad you settled the spelling once and for all. With all these salty railroaders on this forum, I'm very surprised that no one else has jumped in to confirm the word.

I guess that shows that there aren't too many gantlets left.

Jon,

I think I heard about that one and a more recent accident. The Port wine I sip ought to make me sober enough to run the gantlet, but my little engineer will eventually get uclers.

Roger B,

The advantage of a gantlet is that there are no moving parts. Of course the Y is better for routing, but it all depends on the objectives of the little railroad.

Elliot,

Thanks for the diagram, that really shows it clearly. I'm amazed that there aren't any real pictures of gantlets on the Internet (at least the first 7 or 8 pages I browsed in Google).

--------

OK, another modeler found a photo (not too good of a photo) of a gantlet near Roselle Park Station on NJT Raritan Line, which allows freights to clear the station platform. You can make out the 2 rails on the left side, spaced surprisingly rather far apart.
http://www.thebluecomet.com/cr3212rosellepark.jpg

[Kooljock1]

The Rutland and the Central Vermont shared a bridge across the top of Lake Champlain with gantlet tracks. There were no spectacular wrecks that I'm aware of.

But during the grade crossing elimination project on the Long Island Railroad, they used a gantlet track at Rockville Centre to save space. Two high speed, packed commuter trains tried to use said track at the same time in 1950, resulting in an horrific crash.

The way I sometimes run my railroad with a CAB-1 in one hand, and a Grey Goose Martini with a twist in the other...I have to think that a gantlet track would be a bad idea.

Jon [8D]

[Anonymous]

Gantlet appears to be the correct spelling for shared railroad crossings. See
http://www.wordreference.com/definition/gantlet
and
http://www.bartleby.com/64/C003/0140.html

Also, the image shown does not look right! Looking at it more closely, I noticed the image is named Gantlet-Track-joke-620.jpg [:D]

Daniel Lang

[Roger Bielen]

Why bother? Use a single track fed by a "Y" switch at each end. I'm sure there is a way to wire a non-derailing feature that throws the paired switch for a given route.