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Post by edwardsutorik on Jul 31, 2016 10:42:37 GMT -8
I excerpted the following from a Caltrain design handbook after removing what I considered unessential elements:
TURNOUTS AND CROSSOVERS
Turnouts are used for tracks to diverge or converge from one track to another track..
Crossovers are installed between two (2) tracks for trains to move from one track to
another adjacent track. A single crossover unit consists of two turnouts. A
universal crossover unit consists of two (2) continuous single crossovers installed
in opposite directions.
Lateral turnout is a turnout in which the diversion due to the angle of the turnout is
entirely on one side of the track from which the turnout is installed.
Equilateral turnout is a turnout in which the diversion due to the angle of the turnout
is divided equally between the two tracks.
Double Slip switch (or puzzle switch) is a special trackwork unit which allows two
crossing tracks to diverge from one to another. With the approval of the Caltrain
Deputy Director of Engineering, this type of switch may be used at terminals and
yards when the speeds will not exceed 15 MPH.
APPLICATION OF TURNOUTS AND CROSSOVERS
The following standard turnouts and crossovers shall be used according to the
desired maximum authorized speeds (MAS) for operations:
a. Lateral turnouts numbers 8 and 9 for yards
b. Lateral turnouts number 10, 14, and 20 for main line. Number 20 shall be
used where there are no real estate constraints.
c. Number 9 double slip switches may be used in terminals.
Maximum authorized speeds (MAS) through turnouts and crossover for passenger
and freight trains are as follows:
a. 10/10 MPH for turnouts number 9 for both passenger and freight
b. 25/15 (passenger/freight) MPH for turnout number 10
c. 35/25 (passenger/freight) MPH for turnout number 14
d. 50/40 (passenger/freight) MPH for turnout number 20
The above is, of course, a limited statement, in that it is about a particular organization at a particular time (It is dated September 30, 2011. There may be a more recent one. Or not).
It's interesting that the document does not state that the MAS is only for diverging routes. I think it would have been wise to clearly state whether or not that was the case.
Ed
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Post by roadkill on Aug 1, 2016 10:21:51 GMT -8
Sorry 'bout that... Every site/forum/blog seems to have their unique "personalities" I hope the photo is legible.  Photo Credit Josh Nativio: One of the long-time modelers in my area, Harley Smith (Smith & Sons Ballast) has a gauntlet on his HO layout just to make operations interesting! They seem to have a resurgence with the high-speed systems having a platform loading track and a high-speed through track setup as a gauntlet. Would make for an interesting trackage arrangement. I since recall another double slip in the Cleveland area on a main track. The former Nickel Plate/ N&W/ NW at East 34th St. had one, maybe two double slips at their connection with the Erie there. I have video showing the track arrangement as it was in 1973... Now, all I have to do is find it! Also: If anyone is interested here's the track diagram at Leavittsburg  I don't know if a double slip is shown specifically at the crossing. Anyone? Ed That's the best pic yet I've seen of Warren before the reroute, nice! One quibble tho, it's "gantlet" not "gauntlet". |
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Post by gmpullman on Aug 1, 2016 11:26:51 GMT -8
That's the best pic yet I've seen of Warren before the reroute, nice! One quibble tho, it's "gantlet" not "gauntlet". Maybe yes, Maybe not. English language has all sorts of variables. From Wikipedia: Gauntlet track or interlaced track (also gantlet track) is an arrangement in which railway tracks run parallel on a single track bed and are interlaced (i.e. overlapped) such that only one pair of rails may be used at a time. Since this requires only slightly more width than a single track, all rails can be carried on the same crossties/sleepers. Trains run on the discrete pair of rails appropriate to their direction, track gauge or loading gauge. The term gauntlet is derived not from gauntlet meaning a type of glove, but from the expression running the gauntlet (originally running the gantlope) which means running between two confining rows of adversaries; gauntlet in this sense is a "corrupt form". Or the "Free Dictionary" (similar to Wikipedia: GAUNTLET TRACK
Thanks, Ed |
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Post by edwardsutorik on Aug 1, 2016 12:51:14 GMT -8
(gantlet/gauntlet) Here's a couple of interesting thingys to read: grammarist.com/usage/gantlet-gauntlet/latimesblogs.latimes.com/readers/2010/10/gloves-come-off-over-headlines-use-of-gantlet.htmlFor myself, I note that IF you view "gantlet" as based on parallel lines, and "gauntlet" as a glove, there is a pretty clear division/distinction. What causes trouble is allowing "gauntlet" to ALSO refer to parallel lines, but NOT allowing "gantlet" to be a glove. Why the asymmetry? Now, that does not mean that that usage must be incorrect--it's correct if "everybody" uses it. But it kinda muddies the waters. Growing up, I recall the term "running the gauntlet". We all knew what it meant. But I will try from now on to say "running the gantlet". And "throw down the gauntlet". Which I already did. Ed |
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Post by slowfreight on Aug 1, 2016 13:43:18 GMT -8
And IIRC, the CSS&SB referred to the bridge over the NKP and PRR as the "gantlet bridge," since no special gloves were required by motormen operating through the span, those already having been thrown down prior to Kensington interlocking.
A second span was added to eliminate the gantlet arrangement in the 1990s, as red light/green light was apparently too hard to follow.
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Post by fr8kar on Aug 1, 2016 17:01:28 GMT -8
Locally there is a track known as "the Gauntlet" just north of Tower 55. It is not a gantlet track, but it certainly fits the definition of a difficult path in narrow confines. Its origins can be traced back to 1915 when the Cotton Belt constructed a new freight house at 6th Street in a wide spot between the Santa Fe main and the Fort Worth & Denver main. The old freight house was located in a low lying area prone to flooding known as Batter Cake Flats.
To reach the new freight house from Tower 60 (where the original main line continued southwesterly) required crossing the Trinity River at the already crowded area spanned by Santa Fe, Fort Worth & Denver and Rock Island's three parallel bridges. Cotton Belt used the Fort Worth & Denver bridge and a new main was constructed in the narrow sliver of land between the Santa Fe and Fort Worth & Denver main lines. This track was later operated as two main tracks by Fort Worth & Denver and Cotton Belt had to jump through some operational hoops to use it to reach their freight house.
Several years ago in the wake of the BNSF and UP/SP mergers, BNSF gave up ownership of five miles of the FW&D main between Tower 55 (MP 0.0) and North Yard to UP (though trackage rights were retained and BNSF still serves customers on the line). By this time the Cotton Belt freight house was long dormant and the old FW&D Downtown Yard had been reduced to a couple tracks and a single customer. The Gauntlet remained in service, still squeezed in between the main and the embankment supporting the Santa Fe main, with the vestigial Downtown Yard tail track and treacherous crossings encumbering an easy path to the tower. Between these obstacles and the fact that the difficult-to-access north end was protected by the odd non-controlled absolute signal, it lived up to its name even though the days of multiple yard engines from different roads sharing the track was over.
Until the reconstruction of portions of Tower 55 a few years ago it remained much the same. The lone customer at Tower 55 was gone, most of the crossings were closed and most days the Gauntlet was used to tie down ethanol trains until the depot and the TRE dispatcher could handle the train.
Now that the project is complete the Gauntlet is a CTC controlled siding that terminates neatly at the tower with a great overhead signal bridge that leaves nothing to the imagination about when it's your turn to go. And there is certainly nothing worthy of the fearsome name Gauntlet anymore.
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Post by roadkill on Aug 2, 2016 5:44:52 GMT -8
And IIRC, the CSS&SB referred to the bridge over the NKP and PRR as the "gantlet bridge," since no special gloves were required by motormen operating through the span, those already having been thrown down prior to Kensington interlocking. A second span was added to eliminate the gantlet arrangement in the 1990s, as red light/green light was apparently too hard to follow. The mighty Pennsy referred to Gould Tunnel's (just west of Steubenville, OH on the Panhandle) track as a "gantlet" as well. |
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Post by talltim on Aug 2, 2016 13:38:51 GMT -8
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Post by Deleted on Aug 3, 2016 7:38:31 GMT -8
Thanks for that photo, I've never seen anything like that. The model trackwork is beautiful. The only reason slip switches are used on the prototype is to save space. A trade-off of initial & maintenance costs for real estate. That's why they are most commonly seen in busy passenger yard throats where land is expensive. But they can be found elsewhere like at constrained junctions, tight industrial trackage, transit trackwork and rarely in freight yards. Here's an SP example. Situated on the west side of the LA river between downtown and Taylor Yard, this lead separated the "Bullring" and "Corn Field" yards and was referred to by crews as the "Links". I think these were in use into the 70s. 1964 photos by Charles Wherry. Look at all those "Halloween" switchers! More info on Train Orders www.trainorders.com/discussion/read.php?11,3278285,3279523#msg-3279523   |
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Post by talltim on Aug 3, 2016 12:54:19 GMT -8
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Post by riogrande on Aug 3, 2016 13:00:54 GMT -8
Barry slip - had to stare at it for a bit, sort of like a half slip? Funky.
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Post by 12bridge on Aug 3, 2016 15:11:25 GMT -8
 Brooklyn NY, on the BEDT. S. Goldstein Photo. They had several of them. Not really slip switches at all, just a set of tightly overlapped turnouts. |
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Post by talltim on Aug 4, 2016 3:11:22 GMT -8
As if I didn't have enough reasons to want to model the BEDT...
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Post by John Sheridan on Aug 4, 2016 5:04:29 GMT -8
jonklein611, South Station in Boston was built in 1899 with 30 #8 double slip switches, and these were 4-motor (moving frog) slips. Even then, 8-coupled steam engines (4-8-2, 4-8-4, etc.) were banned from traversing any switch when in the slip position as they tended to derail. #8 is about as tight as it gets in the real thing for passenger terminals, and South Station kept the #8's until the mid-1980's. Now they have larger ones. Here's South Station trackage in 1905. Enough #8 Double slips for ya ? .jpg) |
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Post by Paul Cutler III on Aug 4, 2016 7:38:06 GMT -8
John,
No, that's not enough! Must...have...more...slips...
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Post by dti406 on Aug 4, 2016 8:17:48 GMT -8
My wife worked for Cleveland Track Material here in Cleveland for 6 months last year, you might be interested in their website. All the track components are built on the shop floor, then taken apart and shipped to where they are to be installed. www.clevelandtrack.com/photo-video/Rick Jesionowski |
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Post by edwardsutorik on Aug 4, 2016 8:37:22 GMT -8
That South Station photo is a real railroad beauty!
Folks, pay special attention to the slip switch just to the right of the signal bridge in the foreground. Anything "strange" about the installation?
Now examine the positioning of the points for that slip switch. Anything "strange" about the selected route?
One could also consider the semaphore arm position of the signal beyond the subject slip switch.
Yup, a fascinating photograph.
Ed
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Post by jonklein611 on Aug 4, 2016 9:17:56 GMT -8
That South Station photo is a real railroad beauty! Folks, pay special attention to the slip switch just to the right of the signal bridge in the foreground. Anything "strange" about the installation? Now examine the positioning of the points for that slip switch. Anything "strange" about the selected route? One could also consider the semaphore arm position of the signal beyond the subject slip switch. Yup, a fascinating photograph. Ed That's one way to stop a train... |
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Post by Chet on Aug 4, 2016 9:22:58 GMT -8
I have a Walthers (Shinohara) code 70 double slip in my yard and have no problem at all backing a passenger train through it into the passenger station.
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Post by edwardsutorik on Aug 4, 2016 11:07:03 GMT -8
That's one way to stop a train... Yes. A somewhat over-complex derail. But consider the versatility. Ed |
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Post by selector on Aug 4, 2016 12:16:35 GMT -8
The first slip switch shown on that set of proto images posted by gmpullman near bottom of the first page of this thread is a single slip, not a double.
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Post by Paul Cutler III on Aug 5, 2016 7:07:59 GMT -8
Ed,
That double slip you mention is for the never-used commuter loop tracks under South Station. The photo is from 1904, just 5 years after South Station opened. The two tracks you see under the words "By Detroit Photographic Co." originally tied into that double slip. The idea was that all local commuter trains would be electrified using center 3rd rail (like Lionel track) as was being done on the Nantasket Beach Branch of the NH. The double track loop (one ramp from the Old Colony lines, one ramp from the Providence/Albany lines) was to take advantage of this technology with a low overhead clearance and a tight radius curve, which was no problem for the 1890's-era shorty wood cars. It never took off because of the electrocution hazard of the 3rd rail (and the expense).
As a result, the loop became superfluous. They actually tried to run a steam engine through it once...and it almost killed everyone on the test train (there was no venting other than for passengers breathing fresh air). Shortly after that, they cut off the loop tracks from the Fort Point Channel drawbridges and re-routed the two tracks into the main switching plant (as shown). Note the new twin signal bridge located on the other side of "Signal Bridge No. 8".
Later, the ramps and the loop tracks were used by the USPS for an underground terminal for the mail. They built a Post Office above the tracks, then used the loop tracks as stub tracks as basement loading docks.
I know far too much about South Station...
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Post by gmpullman on Aug 5, 2016 14:45:47 GMT -8
The first slip switch shown on that set of proto images posted by gmpullman near bottom of the first page of this thread is a single slip, not a double. As pointed out in the caption. Also, I just happened to be watching the Revelation Video "Erie-Lackawanna Legacy, Disc II and toward the end of the DVD there was a view filmed from the rear of #28 going through Leavittsburg and there certainly was a double slip there, at least in 1966 when the film was made. Thanks, Ed |
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Post by llxlocomotives on Aug 6, 2016 19:56:30 GMT -8
The original pix is probably of a trolley line. The radius on the top curve is really tight and it turns almost 90 degrees. The later pic look to be more the #6 or #8. The speed would likely depend on wether your turning or going straight. The E 222 st. pix looks to be a single slip. Looks like you can turn left, but not right,
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