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From: "Joseph A DOT Braun" joebraun AT optonline DOT net
Date: Tue, 05 May 2009 16:22:55 -0400
Subject: Compound ladders
"Staging_1D_ladder_Photo2.jpg" - image/jpeg, 1000x560 (24bit)

I am back on home turf. I find it so enjoyable when away to get my daily
List whenever possible.

I want to add a thought to the topic raised by Brad. When one sees diagrams
to illustrate compound versus straight ladders, the compound ladder is
usually drawn as a symmetrical design. I want to note that the "form follows
function" dictum applies to the design of compound ladders, so that there
may be lots of assymetry in the final product. The PassLadder photo -- of
the compound ladder for a stub-end passenger terminal -- shows the assymetry
that resulted from the need to have one turnout bear off to the opposite
side and to also maximize the number of tracks that had maximal platform
length (the station platforms will be in the wide gaps between tracks).

The other three photos are successive views of the compond ladder of one
twelve-track, reverse-loop staging area. This entire ladder had to be
curved. Follow the sequence from Photo 1 to 3 and the requisite assymmetry
can be seen. The need here was to keep all tracks and turnouts in the
directional flow of the curve. With stock turnouts, BTW, one can slice the
ties underneath like flex track ties and also cut the long ties at the frog
end that usually bind both main and diverging rails; one can then give some
slight curvature to the turnout to help conform to any design needs.

In designing compound ladders, go with the flow of the basic functional
needs. Some interesting track plan options will arise.

Joe Braun


Staging_1D_ladder_Photo2.jpg

Image EXIF Data:
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Image Capture Date   2009:05:05 13:51:58
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