Double Slip Stub Switch

Model Railroader Prototype information for the modeler
1

I’m looking for more information about Double Slip Stub Switches.

I want to scratch build one in H0n3 and need prototype informations.

Thank you

Wolfgang

2

Interesting. I would never suspected such a thing existed, and seeing it now I don’t think I would have called it a slip switch.

What information do you need? From the pictures in the provided link it seems pretty straight forward. Basically just build two stub switches back to back (is that stub to stub?![:O]).

3

Any information will be good. For now I’ve made a drawing with two stub turnouts. But I would like to build it more prototypically.

There’s one switch stand and you move the rails to the right for the next six ties. You have three positions for four routes.

Wolfgang

4

From the pics you’ve linked to the things are toe-to-toe stub points as posted above.

A single or double slip starts its design with a diamond crossing of two tracks at an angle to each other. A slip then adds either one or two routes that enable movement from one track to the other through a connecting route. This could be done with stubs instead of points.

Sorry I can’t provide pics or a diagram…

Maybe this will make sense…

Take an example of a conventional slip with point blades…

I’m going to have to diverge…

To make a switch stub instead of bladed you would…

  • take away the last 4 metres of so of both blades to the tip …

  • take away the adjacent stock rail (fixed rail) for the same length…

  • replace all this with straight rails pivoted where the tips of the blades used to be.

I hope that made sense!

All you have to do to make a stubbed slip is the same change of blades and stock rails for moveable stub rails.

The big question for most slips would be whether there is enough length to get sufficient switch movement without there being a huge kink in the direction of the rails.

That said…

Most slips are what would usually be known as an “inside slip”.

With an inside slip one of the curved rails of each slip is inside the diamond. [The other one has to be outside]. This is the main thing that limits the lengths of rails in a slip formation… which is the thing that would make a stub slip very difficult.

There is such a thing as an “outside slip”.<

5

You may have all the information there is. I have only seen one picture of such a switch and you already have a link to it.

Its probably not a very common switch arrangement.

6

The keys:

Only one side moves. The other side is fixed.

The switch throw mechanism has to have a center position, rather like a three-way stub switch.

Note that the original was on the U.S. Military Railway - presumably built in Atlanta after Sherman marched out and the fire cooled during the Civil War. Look at the rail - way too light for anything much heavier than a skinny-boilered 4-4-0.

Chuck (Modeling Central Japan in September, 1964)

7

Hi Wolfgang

I would recommend joining the Yahoo Early Rail group as some there also belong to a Yahoo Civil War group. There are knowledgeable CW types in those groups. That switch was used during the USA Civil War, 1861 to 1865. No doubt before also.

I have some USA Civil War railroad books that show that type of switch in some yards. One book I think it was called a puzzle switch.

During the CW here, there was standard gauge and at least two or three broad gauges.

http://groups.yahoo.com/group/EarlyRail/

http://groups.yahoo.com/group/Civil_War_RRs/

Rich

8

This was discussed in a late 1960s vintage “Bull Session” in Model Railroader which is seemingly not indexed as to topic. If I run across it I will try to post the cite to the issue. What I do recall from the discussion is that a stub switch double slip would be in theory the most simple type of double slip.

Dave

9

There is another prototype picture on page 68 of my reprint of George B. Abdill’s book Civil War Railroads. Just like the others have said, it is two stubs back to back, with all four rails from one of the switches running parallel to each other for about 10 ties. It is operated by a 3 position harp switchstand. In the center position, each of the straight routes of each turnout goes to the diverging route of the other turnout. The other positions route straight to straight or diverging to diverging. Except for the moveable section with four rails, it is basically two stubs back to back. I believe that most harps had three positions, even though just two of them were used for a normal stub. The three positions were used for this type of switch and three-way stubs.

BTW, I enjoyed the link to the O scale USMRR railroad!

  • James