Trains.com

Third-Rail Shoes

4358 views
6 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    March 2016
  • From: Burbank IL (near Clearing)
  • 13,540 posts
Third-Rail Shoes
Posted by CSSHEGEWISCH on Wednesday, October 20, 2021 10:05 AM

I've observed over the years that CTA rapid transit equipment has used gravity contact third-rail shoes.  Do any other operations use similar shoes?

The daily commute is part of everyday life but I get two rides a day out of it. Paul
  • Member since
    February 2011
  • 117 posts
Posted by sandyhookken on Wednesday, October 20, 2021 12:45 PM

By "gravity contact", do you mean that there's no spring forcing the shoe onto the rail?

Also, I'm sure that most people are unaware that there are Summer and winter third rail shoes ( no, this is not like summer and winter air for your tires!). The New York City Transit Museum in Brooklyn has a display of the two types of shoes. The summer shoe contact plate is a solid casting, the winter shoe has two large oval holes in the contact plate. The docent explained that the holes minimize the buildup of ice and snow under the contact plate.

  • Member since
    March 2016
  • From: Burbank IL (near Clearing)
  • 13,540 posts
Posted by CSSHEGEWISCH on Wednesday, October 20, 2021 1:49 PM

CTA third rail shoes are not spring loaded.  There are also sleet breakers also attached to the third rail beam.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
  • Member since
    December 2008
  • From: Toronto, Canada
  • 2,560 posts
Posted by 54light15 on Wednesday, October 20, 2021 6:45 PM

On the CTA do the shoes ride on top or the bottom of the contact rail? 

  • Member since
    March 2021
  • 131 posts
Posted by Former Car Maintainer on Wednesday, October 20, 2021 7:21 PM

 Like the trolley poles and pantagraphs there are springs or air cylinders maintaining a positive upward force against the catenary wires. The third rail paddle shoes, such as "BART" maintain a positive downward pressure toward the top of the third rail with a torsion spring. https://s.hdnux.com/photos/45/17/01/9760864/3/gallery_medium.jpg

In areas Where there is sufficient ice build up on the third rail, the third rail can be suspended and the collector paddle is spring loaded in providing upward contact on the bottom of the third rail.

  • Member since
    March 2021
  • 131 posts
Posted by Former Car Maintainer on Wednesday, October 20, 2021 8:29 PM

CSSHEGEWISCH

I've observed over the years that CTA rapid transit equipment has used gravity contact third-rail shoes.  Do any other operations use similar shoes?

 

according to a CTA third rail shoe photo https://upload.wikimedia.org/wikipedia/commons/thumb/0/0c/CTA_third_rail_contact_shoe.jpg/1280px-CTA_third_rail_contact_shoe.jpg

there is a leaf spring damper of some type 

According to https://www.google.com/books/edition/Electric_Railway_Journal/7ahMAAAAYAAJ?hl=en&gbpv=1&dq=Third+rail+gravity+shoe+pressure&pg=PA993&printsec=frontcover

at least 50 lbs of shoe weight is needed in gravity systems for them to work correctly...

  • Member since
    June 2002
  • 20,096 posts
Posted by daveklepper on Thursday, October 21, 2021 8:42 AM

CTA shoes, like those that were used on New York City's Elevated Railroads, both the IRT and BMT operated, press straight down on a relatively high and close third rail.  This does not permit a cover board, but some safety can be provided by a vertical board several inches higher than the third rail agaist the outer side.

Except for Metro North's former New York Central electrtified lines, all other North american 3rd-rail electrifications  use sprung padel shoes that contact the top of the third rail under a braketed protection cover board.  MN's system also buses a padel shoe, but is sprung to press upward agaist the bottom of the third rail located directly under the protection board.

No example of the elevated type of  electrification renmains in use in New York City.

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

Newsletter Sign-Up

By signing up you may also receive occasional reader surveys and special offers from Trains magazine.Please view our privacy policy