RE: Cable tram mechanical details
  Noel Reed

Thanks Dean for that information on cable tram rope and grip manipulation. You mentioned a steel bar across the cable slot to shatter the grip in dire emergencies. This sounds similar to the interlocked steel ‘bolt’ which was moved across the slot in approach to railway level crossings instead of the catch points as used with the electric trams.

The cable ducts on hilly streets must have acted as drains for storm-water and anything else dropped on the road. They must have had a regular duct cleaning procedure to remove the rubbish [or was it flushed into the river?]

Noel Reed. Whoever had the cleaning job must have been the original ‘Drain Man’.

From:TramsDownUnder@... [mailto:TramsDownUnder@yahoogroups.com]
Sent: Thursday, 25 May 2017 9:13 PM
To:TramsDownUnder@...
Subject: [TramsDownUnder] Cable tram mechanical details

I recall reading somewhere, that at certain strategic points a steel bar was so placed in the conduit as to shatter the brittle parts of the grip if the rope (the commonly used term for the steel cable) was not relinquished - grips were relatively easy to repair or replace; the rope was NOT.

.. . . and from the expert himself:

"The Melbourne Cable Trams by A.E. Twentyman"

(Running Journal Volume 5, Number 3; December 1968 – January 1969)

[for an OUT-bound cable tram in Bourke Street, approaching Elizabeth Street] . . . the dummy [comes] to a halt breasting the white marble bar let into the road line of Elizabeth Street . . . the signal to proceed is given . . . and the gripman releasing his brakes, allows the tram to move down the slope, slowly at first, but it gathers speed with the force of gravity to cross the Elizabeth Street cable tracks with the familiar rhythmic tapping as the wheels cross the rails and slot beams.

At this intersection, the Bourke Street cable passes beneath the cable in Elizabeth Street and is permanently depressed to prevent Elizabeth Street grips coming in contact. About twenty yards beyond the crossing, two white bars are seen across the track for at this point the cable is elevated and brought onto a position where, as the grips come through, the cable automatically enters the jaws and when the gripman feels the cable enter the grip, he leans forward and draws the grip lever back into a vertical position . . .. a clang on his bell and a pull on the lever the tram picks up speed . . . soon we reach the Swanston Street corner . . .

The Bourke Street cable passed above that of Swanston Street so our gripman after releasing his brake and pulling his grip lever soon has his tram in motion again

[for an IN-bound cable tram in Bourke Street, approaching Elizabeth Street] . . . The stop at Elizabeth Street corner is set approximately fifteen yards before the corner, as this gave the gripman an opportunity to accelerate then coast across the other lines; the rope is automatically picked up at about the line of the West footpath in Elizabeth Street where at this point there is a sharp change of grade in the road. From almost level it suddenly inclines to a rise of about 1 in 18: the points between which the rope entered the grip appears to be restricted and the gripman had to be wide awake to promptly seize the rope. Because of this restricted pick-up area, it is not unusual to see them miss the rope and if this occurred, then the gripman has to let the tram roll back a short distance to the correct spot; the car obstructing North-bound traffic in Elizabeth Street.

X=X=X

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