Ever assemble a switch kit?

B

bl4882

New member
Hello all,

Most model railroaders are familiar with switch kits, which are turnouts that are pre-manufactured and ready to spike down onto ties on your railroad where you need a number 8 left or a number 6 right. Well, there is a prototype for that, as in this puzzle switch for Bayshore yard just south of San Francisco, circa the 1940s.

http://www.wx4.org/to/foam/sp/san_fran/bay/bayshore_puzzle.html

In Trainz we are used to curves-off-straight turnouts, but in the prototype switches were carefully engineered with the frogs and other components cut and built at the shops, and provided to track crews as kits that were assembled on site. Just like the model, only at 12 inches to the foot scale.:wave:

Bernie.
 
This gets worse when you consider all switches weren't the same. Case in point was the Canadian Pacific railroad. For a time, they used special switches that had no frogs, and didn't break the rails. I've been looking for detail photos of these, but this is the best I've found.

http://catskillarchive.com/rrextra/tkmacph.jpg

As you can see, the switch actually lifted the cars up and over the running rails. The switch, called a MacPherson switch, would also be "knocked" Open if a train tried to come out of the main through the switch, where as for the siding side, it acted as a derail/stub switch.
 
That's amazing Magickmaker. Did they ride on the flanges through what would have been the frog? How would that work?

Bernie
 
From what I understand, the frog wasn't what we'd consider a frog with flangeway, but instead it acted more like a movable rail. So there was no actual break of the rail. It's hard to explain, but as I understand it, the cars were raised high enough so the flange cleared and rode on the tread over the "frog." It was a very unique system that actually saw some use here in the US. Though those were mostly the "Wharton Safety" switch types. Same basic design though.

art2007_26.jpg


The Wharton system was used originally on the Pennsylvania Railway. Quote:

wharton.gif

The main line rails AA and BB are seen to be continuous through the switch, which is shown set for the main line. The movable rails are GH and KH', one with a pointed toe and the other blunt. Typically, they were 18' long, and connected with fishplates at the heeels. When the weight L is moved to the other position, G and K are pressed against the stock rails, and the switch is set for the divergence. From G or K to a distance shown by C, 3' 6", the switch rails rose 1-3/4", a rise of 1 in 24, and were then level as far as their heels. Both the point and the blunt rails rose equally. This rise was not objectionable, since the speed was low on the diverging route, and the rise was experienced by only one truck at a time. Initially, there was a rise of 2-1/2" in 2', which did prove too abrupt. The guard rail E, which was rigidly attached to the switch rail, kept the wheel set over so that the flange of the opposite wheel did not touch the stock rail BB as the wheel was raised while the outer part of its tread rode on the switch rail KH'. When this wheel was raised the full amount, the flange then moved across BB and assumed its normal position on the diverging route. Later, the switch rail GH was rolled in one piece with the guard rail.

A cut from the Wharton catalog shows the switch layout. When the switch is set for the main line ("open" in Wharton terminology, but normally called "closed") the main line rails are continuous and uninterrupted. Note the pivoted "trip rail" that will throw the switch in case a train approaches from the heel direction. It should be clear how the outside of the wheel tread rides up on the inclined rail until the flange can pass safely over the stock rail. The single point guides the other flange, moving the wheel to the right.


Quote ends here.

It's worth noting that these were VERY popular for a time when stub switches were more common. As better designs of frogs came about, companies started converting their Wharton and Macpherson switches over. However, a couple of Wharton switches stayed in regular use up to the 50's, especially in locations that required the use of a derail. Since the switch itself served both purposes, it made construction and safety a good bit easier. I originally found out about these some years ago after stumbling over a website detailing a new "Switch" this company had designed that operated manually but didn't require the company to "break" the rails like a normal switch did. That switch was very unique in that the switch man basically used a lever to physically move a car over to the new track. Not by throwing points or anything, but actually lifting up the bogie and moving it over. The fact that the company boasted this could be done by a single man blew my mind. I've searched for that company's page and photos since, but I've long since forgotten where I found it, or more over what I was searching for originally when I discovered it.
 
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Thanks for that information. I had heard about innovative switches and other types of trackwork, but never spent much time researching it. You've piqued my interest so now I think I will.

Bernie
 
Well actually turnouts are quite interesting,when not(and when they are) attached to the rest of the railway.
They ride on flatcars(or maybe gondolas) to the maintenance area,crossties and all!So seeing some on a work train isn't that rare.


also you've piqued my interest as well,being interested in USA Railroad history and everything,thanks for the info
 
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