[PRCo] Re: Fineview___PCCs

[Boris Cefer]

> > Wasn't the problem of all-electrics in lack of drum
> > brake adjustment?     Maybe no. The soft adjustment
> > of standard all-electric drum brake would provide
> > very long stopping distance on steeper downgrade and
> > the shoes would suffer heavy wear.
>
> Do you mean:
>
> 1.>-- Lack of adjustment built into drums?

No, at least WABCo SE-2 electric actuator had an adjusting worm gear unit
and I think also the brake itself was adjustable. I suppose the brake key
had two screws to adjust proper distance between drum and shoes, each shoe
could be adjusted separately.

> 2.>-- Lack of adjustment by maintenance teams?
>
> In either case, track brake had 2-settings, the
> first being moderate.     Not at all unusual for moderate
> track brake to be applied during normal service stop.
> This would help make the final stop and once stopped,
> then the track brake would release allowing drums to do
> their job.     Most cars would hold but obviously
> there will be exceptions with wear and tear!     And
> if all else fails, hold the track brake on  --  Not
> So Difficult.     Did it on occasion here in SF.     Had
> one Baby-Ten (aka PRCo-1700 except believe the drums
> were internal expansion on the B3s) at Church and 19th
> Inbound where center door wouldn't close and car would
> not hold in service latch.     Put the brake to the floor
> activating the track brakes and hooked the brake there.
> Car held.     Got out of seat and manually closed
> center door, then continued!
>
> Problem with #1 above is that, without possibility
> of interim adjustments, braking integrity is consistently
> lost as the drums wear!
>
>
>
>
> > Maintenance specification we use here for drum brake
> > says that each car must be tested by removing of drum
> > brake fuse and pressing power pedal to reach starting
> > current of 290 Amps - drum brakes must hold the car
> > (on dead level track).      290 Amps cause approximately
> > the same traction effort as 9.5 % downgrade.      Sometimes
> > we experience drums which are sufficient to hold the
> > car at 350 Amps, which would be about 11.5 % downgrade,
> > but this is with new brake shoes and freshly adjusted brake.
>
> Assume this is Dead-Empty Wehicle, No?! :)

Yes, empty car.

>
> > But if you find any drawing and cpecification for
> > WAB drum brake and actuator at Arden (that would need
> > some work - consign it to limbo), I can easily made a
> > calculation and answer the question of maximum grade
> > which allows drum brake operation.
>
> > Or you can ask Tony, I think he has some experience]
> > with 1700s.     I am curious what he knows about drum brakes.
>
> Do you mean Bernie Orient?     He seems to be
> very much up on equipment specifications.     Know the
> name Tony DeSensi but haven't seen him referenced in
> Trolley Fare recently.

Meant Tony DeS. Didn't he work at Charleroi CH?

>
> <><><><><><><><><><><><><><><><><><><><>
>
> Jim
>
> <><><><><><><><><><><><><><><><><><><><>
>
>