The Drake Photos - Single Point Turnouts -- Module Progress!

[Jim Holland]

Greetings!

	My Thanks to Ed and Derrick for taking the time to scan and post the
photos!
	Hard to believe that these photos date back almost 50-years!

Dietrich, Robert J. wrote:

> Say isn't the movable point on the "wrong" side.  It makes sense to be there
> but I was under the impression that putting the movable point on the inside
> of the curve was the exception to the rule.

	No - this is the rule!  *Most* trolleycar properties followed the rule
of the point on the inside track of the curve.  One notable exception to
that is LATL - the narrow gauge system had the point in the outside
rail.  And even on properties following the rule of inside track for a
point, there will always be exceptions.
	If you look closely at the point, you will note that at the hub where
it pivots, the point head is as high as the guardrail going into the
curve, and the guardrail is about 3/8" higher than the rail head.  It
doesn't seem like much, but an extra 3/8-inches of guard is almost
doubling the area on the wheel surface which helps in protecting against
derailment.  And in the case of the point in a turnout, it helps
dramatically in guiding the opposite wheel through the mate.
	Thus a car going straight thru such a switch finds the track slightly
higher going thru the point; the short section of tangent connected to
and a part of the point - just several feet - brings the rail back down
to grade.
	In issue #50-3, September 1964, of *Trolley Talk* (Bound Volume #3) is
a photo at Tioga loop where an outbound 76-car on Tioga can make a left
turn into the loop - the point is in the outside rail of the track.  The
letter accompanying the photo reads::
	"The enclosed photo will, perhaps, settle once and for all the age-old
argument as to whether or not traction companies ever put the moving
switch point in the *outside* mate [rail!]."
	"This one exists today in Pittsburgh and is still in use.  It can be
found at the intersection of Tioga, Oakwood, and Wood at the end of the
Frankstown line (#88)."
	"Actually, Cleveland had several of these outside-point switches.  I do
not know why certain turnouts were built this way.  In the few cases
that I have known, it has not been a problem of 'compound' switch
crowding (such as the one in the enclosed photo).  Samuel H. Caldwell,
Gambier, Ohio."
	Also, the inbound track at Dawn Jct. (south end of Palm Garden Trestle
where 42-38-39 lines diverge) has the point in the outside rail but this
is a trailing point.  I also believe that the switch for the
98-Glassport as the car left the McKeesport line heading toward
Glassport has the point in the outside rail.  I have seen other examples
on PRCo but can't recall them at present.
	Rationale for this is assumed for the present.  In the case of Tioga
loop, the need to use the turnout is extremely rare and it would be much
smoother riding for the outbound 76-car without going over the point
which rises to make a guardrail for the turn.  Thus the favored
direction would not ride over the point.  Also, construction details at
various locations might favor the reverse of the general rule, although
none of the above examples would seem to fit this category.
	But there can be problems with this arrangement which will definitely
cause derailments.  With the mate on the inside rail, cars going
straight through will wear distinct grooves in the rail head of the
mate.  These grooves can be so deep as to make like a guard rail so when
the diverge movement is desired, quite often the grooves in the mate
will overide the direction of the point so that an axle or truck goes
straight thru rather than following the turnout.  And usually it is the
trailing truck that does this - saw that happen here in San Francisco!
	To Bob Dietrich:  from the infrequency of your posts, it seems like you
are not able to read your email as frequently as the rest of us, so I
don't want to impose on your time and don't want you to feel obligated
concerning the following observations and questions.
	In the recent discussions on SHJ, you listed many details about the
track and rail and where girder began and ended.  Will you be using
girder rail (possibly Orr) for your HO module?  Will you use single
point turnouts?  It sounds as though this junction will be completely
custom built; definitely look forward to your progress with this
project!

James B. Holland
------- -- ---------
        Pittsburgh Railways Company (PRCo), June of 1949 -- June of 1953
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