Jack,

156# was a slip on my part in the intial thread that I later corrected to 155#

regards
Bruce Smith
Auburn, AL
________________________________________
From: STMFC@yahoogroups.com [STMFC@yahoogroups.com] on behalf of moonmuln [jack.f.mullen@gmail.com]
Sent: Friday, February 08, 2013 11:58 PM
To: STMFC@yahoogroups.com
Subject: [STMFC] The wheels on the bus go round and round, was Re: Revell Flatcar

I'm puzzled by the references to 156# rail. PRR's 152# and 155# sections are documented in (prototype) engineering literature and vendor's catalogs, but I'm unaware of 156#. Is this just a typo that's been perpetuated in this thread, or was there a third heavy rail section on the Pennsy? My recollection is that the 152# rail was designed in the late '20s, and the 155# was an improved design dating from sometime in the '40s. Overall dimensions remained the same: 8" h., 6 3/4" base, 3" head width. The 155# section had a deeper, redesigned head and improved fillet between head and web.

Both sections were introduced many years after the the I1s type and other heavy power was placed in service. Obviously I1s could and did operate safely on lighter rail. The purpose of moving to heavier rail sections was to attain an improvement in service life that would more than offset the cost of the added metal. Locomotive characteristics, axle loads, gross tonnage, operating speeds, grades and curvature are factors that come into play.

FWIW 8" is around 0.092" in HO, so code 100 is about 9% oversize in height.. In O, code 172 is about 3% over (for 48:1) or under (for 45:1), so perhaps you should consider a different scale. ;>)


--- In STMFC@yahoogroups.com, SUVCWORR@... wrote:

I don't know about 156# rail but I have track charts of the Connemaugh
Div (1940), Pittsburgh Div (1951 and 1958) and Cresson Branch (1951 and
1956) all with 152# rail for the mainline and the primary track of the
Cresson Branch.

Rich Orr


-----Original Message-----
From: Bill Daniels
To: STMFC
Sent: Wed, Feb 6, 2013 2:02 pm
Subject: Re: [STMFC] The wheels on the bus go round and round, was Re:
Revell Flatcar


David, I would humbly disagree with you regarding both of your
comments. First
of all, the PRR used their 156 lb. rail on their mainlines throughout
Pennsylvania, on both the Middle Division and on both sides of the
climb over
the Allegheny Mountains. The reason for this heavy rail was NOT due to
traffic
weight, but to absorb the heavy pounding of the locomotives that were
used on
these lines (primairly class I1sa with an main rod thickness of 11.75"
at the
end of the rod). Once the diesel had banished the I1s, the PRR relaid
the line
with 132 lb. rail.
Â
Bill Daniels
San Francisco, CA



________________________________
From: David
To: STMFC@yahoogroups.com
Sent: Wednesday, February 6, 2013 10:11 AM
Subject: [STMFC] The wheels on the bus go round and round, was Re:
Revell
Flatcar


Â
--- In STMFC@yahoogroups.com, timboconnor@ wrote:

Bruce, I know that's true, but how common was 156lb rail on the PRR,

really? I
grew up in PRR territory and none

of the rail I ever saw was 156lb. Of course I didn't go out on the

Middle
Division, maybe that's where they used it...

IIRC the 156# stuff was only used on the line from Pittsburgh up to the
Lake
Erie ore docks, and maybe a handful of other small locations. The rest
of the
main system was the usual 120-130# rail that everyone else used for
heavy
traffic. Code 100 rail really should be banished from HO on general
principle.

David Thompson




[Non-text portions of this message have been removed]



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