Would anyone mind giving me their thoughts about using a single slip turnout rather than a double slip one,...positives vs negatives.??
I have in mind a place where I think the single slip would be advisable over a double, but before descrbing my particular situation I was looking to hear generalities about the two.
Brian
My Layout Plan
Interesting new Plan Consideration
For all intents and purposes, slip switches are crossings that're made up of a pair of turnouts (single-slip) or two pairs of turnouts (double-slip).
If you have some track on hand, you can make your own "model" of a slip switch pretty easily, by using two turnouts (1 each left and right-hand) of the same frog number (e.g. 6).
A double-slip is effectively options 1 and 3 or options 2 and 4 laid over each other.
-Dan
Builder of Bowser steam! Railimages Site
The railroads preference is the simpler (and cheaper) the better. That is why slip switches are only found where there is absolutely no alternative. A single slip switch is simpler than a double slip switch, so if that is all that is needed, that is what is installed. In practice they were comparatively rare.
Paralleling the above statement, if a railroad determined that the "other" route would not be (or "rarely") used, then a single slip would be installed.
Ed
A single slip switch is a combination of a one-way crossing, depending on direction of movement, and a turnout to afford directional change onto only one route, depending on direction of movement. So, intended traffic patterns matter there. Where trains moving in one direction must not be permitted to encounter other rail traffic, but may 'slip' onto an adjacent parallel route, the single slip works...again, in the one direction.
A double slip comprises TWO crossings, both directions of movement, plus two slips permitting access to (proximally) two parallel tracks on either side of it. They would be found in terminal yards with no through traffic, such as a passenger terminal where trains must return from whence they came in order to join the main line(s), or continue in the same direction if it's a through terminal. They permit various access to the 'throat' comprising two or more parallel leads that eventually lead to routes going in several directions to several destinations.
Contrary to common opinions, such slips are rather frequently seen, especially still in Europe, and most frequently at stations with multiple tracks and multiple routes where trains must be shunted across several parallel tracks in succession, but allowed to join any one of them if that is to be the train's defined path for ingress and egress.
railandsail Would anyone mind giving me their thoughts about using a single slip turnout rather than a double slip one,...positives vs negatives.?? I have in mind a place where I think the single slip would be advisable over a double, but before descrbing my particular situation I was looking to hear generalities about the two.
I have four Peco Code 83 double slips on my layout and one Walthers Shinohara Code 83 double slip. There were situations where I would arguably be able to use a single slip, but I still chose the double slip because it is more versatile and therefore preferable to the more limited function of a single slip.
Perhaps more importantly, there is usually no difference in cost between a single slip and a double slip.
I can tell you this. The operation of a double slip is complicated whether it be operated manually or electronically. That said, once you get the hang of it, operation of a double slip becomes somewhat intuitive.
On the prototype, slips were mainly used when and where space was limited such as in yards and larger stub end passenger station tracks.
Rich
Alton Junction
Rich, I was going to email you, but why not make my question public? Can you post a couple pics of your double slip switches?
I bought one thinking I could make a double crossover in a smaller footprint and that was a flawed idea for a couple reasons. So I am trying to figure out how to best utilize it.
Henry
COB Potomac & Northern
Shenandoah Valley
BigDaddy Rich, I was going to email you, but why not make my question public? Can you post a couple pics of your double slip switches? I bought one thinking I could make a double crossover in a smaller footprint and that was a flawed idea for a couple reasons. So I am trying to figure out how to best utilize it.
Here is a closeup of one of the Peco Code 83 double slip switches.
These are spring loaded switches that I operate with a flip of the finger against the point rails.
Thanks Rich
Single or Double Slip Turnout
So here is my particular situation. I have two spur lines off of the mainlines feeding my peninsula area. It is desired that these 2 entering lines be able to select between either of 2 lines themselves. The most 'compact' manner to do such a thing is a slip switch.
A single slip switch accomplishes just what I want to do,...take the entering train and curve it around onto the same side, or cross it over to the other side. It does this in one single selection of the controller. It can remain on one single selection and do the same thing for trains entering from either track,...cross them over, or leave then curving around on the 'same track'.
Another nice feature of the single slip is that should the train stop, then get reversed while over this turnout, the train will NOT try to pick the opposite track and derail,,,as it might well do on a double slip switch. Is my thinking correct??
Since the double slip switch has 'another set of point rails' at its other end, that ARE NOT always set in the correct position, the train could well back up and try to chose a different route than it came in on. In other words it requires 2 control settings to get the dbl-slip to act in the manner I seek above, ….plus when I change the incoming route I have to make TWO selections to get it to operate like the single slip that I did not have to make any new selections.??
Overall view (sorry, still just a paste in for the peninsula plan as I have not finished final plan for it)
Enlarged peninsula (again, somewhat representative)
Slip switch location
Single or Double
The 2 tracks coming off the slip switch will be feeding the two container unloading/loading tracks located either side of that 'passenger station' in the original Tupper Lake plan.
The track on the left next to the aisle will be the 'escape track' for the locos that pulled the trains into the peninsula area to escape back to the freight yard area or the turntable,...a 22” radius one & a 24” radius one for bigger steamers.
Container crane (block of wood) straddling container tracks
railandsail Single or Double Slip Turnout So here is my particular situation. I have two spur lines off of the mainlines feeding my peninsula area. It is desired that these 2 entering lines be able to select between either of 2 lines themselves. The most 'compact' manner to do such a thing is a slip switch. A single slip switch accomplishes just what I want to do,...
A single slip switch accomplishes just what I want to do,...
Well, there's your answer. In my opinion. Railroads don't just use the double slip because it's cooler than a single. If you are never going to use the "other" route, why allow for it?
...take the entering train and curve it around onto the same side, or cross it over to the other side. It does this in one single selection of the controller. It can remain on one single selection and do the same thing for trains entering from either track,...cross them over, or leave then curving around on the 'same track'. Another nice feature of the single slip is that should the train stop, then get reversed while over this turnout, the train will NOT try to pick the opposite track and derail,,,as it might well do on a double slip switch. Is my thinking correct?? Since the double slip switch has 'another set of point rails' at its other end, that ARE NOT always set in the correct position, the train could well back up and try to chose a different route than it came in on. In other words it requires 2 control settings to get the dbl-slip to act in the manner I seek above, ….plus when I change the incoming route I have to make TWO selections to get it to operate like the single slip that I did not have to make any new selections.??
...take the entering train and curve it around onto the same side, or cross it over to the other side. It does this in one single selection of the controller. It can remain on one single selection and do the same thing for trains entering from either track,...cross them over, or leave then curving around on the 'same track'.
I am not following your reasoning here, on operation or control.
However. Since I advocate for the single slip, it then follows that you must be able to control it. So, as they say: "Do what it takes." The same would be true of the double slip.
One other factor that might enter the equation, there are not many single slips sold, and I have only one that is a brass one. I have multiple numbers of double slips in NS
I am not following your reasoning here, on operation or control.Ed
Did I not explain it correctly, or is there another question I have missed??
railandsail One other factor that might enter the equation, there are not many single slips sold, and I have only one that is a brass one. I have multiple numbers of double slips in NS
If you can't find an appropriate single slip, you are "stuck" with a double. You could argue that the double was used instead of a single because your railroad had a FREE spare. I can imagine that happening.
I am not following your reasoning here, on operation or control.Ed Did I not explain it correctly, or is there another question I have missed??
Perhaps you did explain it correctly. I am just not following it. But you already said that a single slip was appropriate, and I believe you. So I don't need to follow the explaination of why.
Like a slip switch, but not a single or double slip
cx500 Perhaps I should also mention that as well as single slip and double slip turnouts, another related design was a diamond crossing with movable point frogs for the center pair. These would be used where the crossing angle of two lines was very shallow, I'm guessing about 6 degrees or less.
Perhaps I should also mention that as well as single slip and double slip turnouts, another related design was a diamond crossing with movable point frogs for the center pair. These would be used where the crossing angle of two lines was very shallow, I'm guessing about 6 degrees or less.
This is one of the first mentions I've seen of such a turnout. I think I have such an animal I first referred to as a single slip. It says 'Atlas' on the back #NS4547, Made in Austria,...likely a Roco.
railandsail This is one of the first mentions I've seen of such a turnout.
The movable point frog is only part of a turnout or crossing. In the example of a crossing there is no turnout at all (i.e. no choice of diverging routes) the design of such a frog is to reduce impact wear at the point of the frog itself.
Some are sprung, others have actuating levers connected to an operating mechanism, either levers in a tower or remote motor drives,
Frog_Sprung_drawing (2016_08_17 08_08_12 UTC) by Edmund, on Flickr
Here is an example of a single-slip on the New York Central main east of Collinwood Yard in Cleveland, Ohio at BR Tower, MP 171.
CP171_BRtower by Edmund, on Flickr
Regards, Ed
railandsail Single or Double Slip Turnout So here is my particular situation. I have two spur lines off of the mainlines feeding my peninsula area. It is desired that these 2 entering lines be able to select between either of 2 lines themselves. The most 'compact' manner to do such a thing is a slip switch. A single slip switch accomplishes just what I want to do,...take the entering train and curve it around onto the same side, or cross it over to the other side. It does this in one single selection of the controller. It can remain on one single selection and do the same thing for trains entering from either track,...cross them over, or leave then curving around on the 'same track'. Another nice feature of the single slip is that should the train stop, then get reversed while over this turnout, the train will NOT try to pick the opposite track and derail,,,as it might well do on a double slip switch. Is my thinking correct?? Since the double slip switch has 'another set of point rails' at its other end, that ARE NOT always set in the correct position, the train could well back up and try to chose a different route than it came in on. In other words it requires 2 control settings to get the dbl-slip to act in the manner I seek above, ….plus when I change the incoming route I have to make TWO selections to get it to operate like the single slip that I did not have to make any new selections.??
With a single slip, there are only two sets of point rails, but there are still two throwbars. So, typically, it still requires two actions to set the route.
A Case of Mistaken ID, ….Single Slip or What?
All of the slip-type turnouts I had in my possession were double slips by Peco and Roco. There was no doubts that these were dbl slips.
I had another slip turnout that I just assumed was a single slip as it had only one control motor. Now I am unsure if I identified it correctly?? Here is a photo of the two types together.
Then here is a photo of that mysterious turnout I first identified as a single slip. It is labeled an 'Atlas', made in Austria (likely by Roco), #4547. As I inspect it more closely it appears NOT to be a single-slip in our conventional thinking, but rather some 'automated crossover' ??
Here are a couple of other photos I found on the internet,...
Has anyone else experience with such a turnout? ...and how would you name it??
railandsail...and how would you name it??
They are all double-slip switches.
Good Luck, Ed
Here is a single slip switch by Roco:
Here is one by Peco:
The ones Broan pictures are all double slips for sure. While there may be 4 sets of points in a double slip, there's no reason to use 4 switch motors, because some of the routes are conflicting. Really the only valid settings are for the two tracks to cross over, or to stay on the same side. Havine once unput crossing over and the other input staying straight makes no sense, even though it's possible to set it that way with multiple point motors. Looks like those pretty much just use 2 solenoids, to avoid crazy mechanical linkages to operate all the points from one.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
gmpullman railandsail ...and how would you name it?? They are all double-slip switches. Good Luck, Ed
railandsail ...and how would you name it??
rrinker The ones Broan pictures are all double slips for sure. While there may be 4 sets of points in a double slip, there's no reason to use 4 switch motors, because some of the routes are conflicting. Really the only valid settings are for the two tracks to cross over, or to stay on the same side. Havine once unput crossing over and the other input staying straight makes no sense, even though it's possible to set it that way with multiple point motors. Looks like those pretty much just use 2 solenoids, to avoid crazy mechanical linkages to operate all the points from one. --Randy
7j43k Here is a single slip switch by Roco: Here is one by Peco: Ed
If these two are BOTH double slip switches, why is the one on the right so much more complicated then the one on the left??1) requires 2 switch motors rather than a single?
2) requires two operations to change from a simple crossing to a curved diversion
3) and requires a third input to change the crossing function from one side to the other.
The slip switch on the left with only a single switch machine in one position acts like a plain crossing to any trains entering it from either direction, and in the other position it acts like two side by side pieces of curved track. (the one on the right does NOT act in that same simple manner)
1: The switch motor on the left is designed to throw BOTH sets of points at the same time. Motor on the right only has the "mechanicals" at one end, thus two are required. The manufacturer chose this method so that a standard switch motor could be used rather than a special designed double-ended motor.
2: you are still doing "two operations" just that both are done by one motor (left) or two single-ended motors (right).
I use Shinohara double slips and have a Tortoise at each set of points. There are four combinations needed (Motor A: N or R and motor B N or R)
I use a rotary switch to choose my routes, very easy and straightforward. Everything here is lined for the main: (straight through)
CP_Union_model_C by Edmund, on Flickr
CP_Union_model by Edmund, on Flickr
The LEDs tell me at a glance what my route is lined for.
CP_Union_west by Edmund, on Flickr
EdI use a rotary switch to choose my routes
Are rotary switches still readily available?And I would need to figure out how to do such a 'control board' on a layout that plans on just using a wireless DCC (NCE) system for train control and PRIMARILY manual turnout controls.
Ken There’s more to the difference than that. What you’re calling the US style ones have a single throwbar at each end to which all four points are physically attached. That simplifies the mechanics. What you’re calling the Euro ones have two throwbars at each end, each with two points attached, that move in opposite directions. I strongly suspect the underlying reason for the difference is that in the four throwbar approach, if you don’t want the giant unprototypical blob next to the slip you’re going to have either a complex linkage under the roadbed, or four switch machines. Where as with the two throwbar approach, you have a simple linkage under the roadbed with two switch machines. Of course if you don’t mind the giant blobs next to your slips instead of scale switch machine linkage standins, then there is some advantage to the four throwbar approach given that you can control it with a single switch and have no possibility of a mis-set point on the far side.
There’s more to the difference than that. What you’re calling the US style ones have a single throwbar at each end to which all four points are physically attached. That simplifies the mechanics. What you’re calling the Euro ones have two throwbars at each end, each with two points attached, that move in opposite directions.
I strongly suspect the underlying reason for the difference is that in the four throwbar approach, if you don’t want the giant unprototypical blob next to the slip you’re going to have either a complex linkage under the roadbed, or four switch machines. Where as with the two throwbar approach, you have a simple linkage under the roadbed with two switch machines.
Of course if you don’t mind the giant blobs next to your slips instead of scale switch machine linkage standins, then there is some advantage to the four throwbar approach given that you can control it with a single switch and have no possibility of a mis-set point on the far side.
Good point Ken, something I hadn't even considered.
One must use that 'included' switch machine with this 'euro style' double slip, because that is where the different mechanical linkage is for the 'opposing throwbars'.
railandsail EdI use a rotary switch to choose my routes Are rotary switches still readily available?And I would need to figure out how to do such a 'control board' on a layout that plans on just using a wireless DCC (NCE) system for train control and PRIMARILY manual turnout controls.
Definitely - although technically you only need a toggle switch, same as any "regular" turnout, since you're only ever going to have "straight through" or "diverging".
That being said, the rotary switch would be a helpful indicator that "this isn't a normal turnout".
Which Type Double Slip to Use?
So here is my particular situation. I have two spur lines off of the mainlines (those 2 white curves at the top of the photos) feeding my peninsula area. It is desired that these 2 entering lines be able to select between either of 2 lines themselves. The most 'compact' manner to do such a thing is a slip switch.
We have now determined that I have 2 types of double slip turnouts,...one that is controlled by a single mechanism, and one that is controlled by two mechanisms.
First Question: Is there a preference for which style of double slip to use here? Does one have capabilities that the other does not??
Second Question: Switching routines (a subject I am not familiar with at all). Lets suppose a fairly long freight train attempts to enter the peninsula area on one of these two 'spurs' off the mainlines. Then it is desired to divide this consist up into groups of cars that might be taken to either of the 2 container tracks. or switched off that dbl-curve turnout (the one that follows the dbl-slip) into other portions of the peninsula complex. I suspect some of this 'sorting of the cars' would involve the heavy use of this dbl-slip turnout that is in question, and the other incoming track as a temporary holding track? Plus the switching loco, that is pulling these groups of cars, needs some sort of way to get back around to the front of these deposited cars to pick up more singular or groups of cars??
Maybe I should ask this 'switching question' in its own separate subject thread??
NeO6874Definitely - although technically you only need a toggle switch, same as any "regular" turnout, since you're only ever going to have "straight through" or "diverging".
Not quite...
I remember having an old, brass-rail AHM double slip. Maybe it was made by Roco or one of the other suppliers at the time. The way the points were arranged, all you needed to have, as you describe, was one toggle (momentary) and the route set for X or )( that was the only two choices. I think it even came with a lever-type actuating switch.
Now, on my third layout, I decided to use Shinohara code 83 track which, in the early 1990s, had a rather large inventory of switch configurations.
The double slips had confounded me at first since the "Entrance" and "Exit" points had to be aligned separately. So, you would need two toggles because each route required each Tortoise (or any other machine) to have four different arrangements, as I show A-B-C-D on my panel.
If you simply set the entrance points to normal but didn't set the exit points properly you would have a derailment. So instead of X or )( you could only choose / or \ or ( or ) Each one required its own arrangement of the points.
Using DCC or Panel Pro I'm sure there are route-control macros that you can set up "Entrance - Exit" routes like some interlocking plants have. Again, for MY use, the rotary switches perform flawlessly and operators have a good grasp of selecting the correct routes.
Cheers, Ed