Pa Trolleys Vol 3 -- PRCo -- WP -- JTC

[Jim Holland]

Greetings!

Jim Holland wrote:

>         03)--   The trolley wheels were very hard on the overhead wire
> and caused considerable wear.  To counteract this, PRCo would wrap
> sleeves of copper or phosphor-bronze around the overhead where this wear
> occurs.  This is most noticeable leading into and out of frogs,

	An excellent example of this overhead construction is in the book 
*Touring Pittsburgh by Trolley* by Harold A. Smith, pg 43.  Car 1442 is 
leaving a siding on the 65 Lincoln Place line and the frog it is approaching 
has these sleeves wrapped on all three wires.
	Note the *fourth wire* leading to a strain insulator.  There is 
tremendous weight associated to the overhead and thus tremendous pull as 
well.  That fourth wire is probably the one that 1442 is currently using.  It 
runs into the frog and is clamped to the top and then comes off the frog to 
be anchored to a pole to minimize pull and strain on the overhead (if this 
was an extension of the other wire from the siding, there would be tremendous 
sideways pressure on the span holding the frog in place because of the 
*curve* in its direction through the frog.)
	We were having a real problem with a new frog here in SF once 
travelling into the frog - the trolleys would consistently take the wrong 
wire!  One of the inspectors dispatched to the scene put the trolley on the 
*fourth wire* to get around this dewiring - ha ha ha ha ha ha!  The real 
problem is that someone ordered frogs made for trolley  WHEELS  and not 
trolley  SHOES!!!
	What's the difference?  The wheel touches the base of the frog at 
only one point on the wheel and thus needs longer overlapping runners through 
the frog to guide it.  The trolley shoe had 3-4 inches of flat surface to 
travel on the frog and the runners are shorter and do not overlap!

	I was also looking for several examples of NC - Non Clearance - 
curves.  While I found some possible candidates, the indicators in the 
trolley wire were not clear and it would only be my assumption that this was 
the case with these curves.  If I can find such a picture, I'll ask Derrick 
to post it on the site!

-- 
James B. Holland
       PITTSBURGH RAILWAYS COMPANY (PRCo), June of 1949 -- June of 1953
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