[PRCo] Re: Pittsburgh Overhead

[James B. Holland]

Rolling bronze wheel is constantly arcing since it is constantly making 
and breaking  (braking? :-) )  contact and a number of udder things.

Yes, The Wheel Does Make Good Contact at hanger point because hanger is 
wrapped around the wire from the top with bevel and taper on the lower 
side.       The biggest problem is if an armor protector is then wrapped 
around the wire from below to protect the ear  --  this causes a slight 
bump.       Also a source of arcing, Which I Like  (as Ike)  but also a 
source of overhead wear.

I liked this.       Loved riding the interurban at night because I could 
see the inside and outside lights flicker ever so slightly as the wheel 
hit an armor and bounced ever so slightly  --  I could even feel the 
power interruption!

Solly, Cholly  --  donut at all believe that PRCo PCCs suffered from a 
lack of juice because of the bronze wheel on trolley ears  --  we had 
those puppies rolling right along Many A Time right up into the Very 
Early 1960s.       YOU  Should  KNOW  That  since you worked for PRCo in 
a former life!! :-P

More tension required to keep a wheel in good contact with the overhead 
than is required with a shoe.       Even with increased pressure on a 
wheel equipped pole, PRCo trolley poles did not do damage to the 
overhead on dewirement.

So there  --  I Am Giving Some Argooments From Your Side.       And your 
comments about disagreement  (Contrary Points would be better wording as 
we really aren't disagreeing!) could also be Reverse Sickology to force 
me to stop commenting  --  but don't want to so disappoint you!!!

down with pantographs    ----    UP___WITH___TROLLEYPOLES!!!!!!!


JIM


PS  --  pans in rear of car not so bad but agreed that Europa trams look 
better with pans.



Boris Cefer wrote:

> In my opinion, the US PCCs look ugly with PTG. Everything is only a 
> custom.       But the rolling bronze wheel does not provide good 
> current supply at the points where the trolley wire is kept by the 
> hanger sleeve.
>
> I know that each my disagreement with you will force you to come with 
> some of your PCC memories. And that's the intent! :-) ;-)
>
> B
>
> ----- Original Message -----
> From: "James B. Holland" <PRCoPCC at P-R-Co.com>
> To: <pittsburgh-railways at dementia.org>
> Sent: Saturday, March 19, 2005 11:57 AM
> Subject: [PRCo] Re: Pittsburgh Overhead
>
>
>> If the pantograph has any real *Operational* advantage over the 
>> trolley pole, it is just marginal at best.
>>
>> Dewirements of Trolley Poles do *Not* Mean Damage -- can Not Think Of 
>> Even One Instance where a TrolleyCar Trolley Pole dewirement caused 
>> damage -- It IS possible, but It IS unusual!
>>
>>
>> A catcher works via centrifugal force and just stops the upward 
>> motion of the pole and since the pole is at wire height when it 
>> dewires the best a catcher can do is stop the pole so the Top Of The 
>> Pole is several feet above wire height. There is a crescent shaped 
>> lever on the back of the rope take up spindle which is held in place 
>> by a spring -- fast outplay of the rope -- centrifugal force with 
>> which You Are Well Familiar -- causes the crescent lever to move out 
>> and engage teeth in the outer perimeter which then stops the upward 
>> movement. Relaxing the tension on the rope and allowing the wind up 
>> spring to wind the rope in releases the crescent lever which is 
>> spring returned to its holding pattern and the rope wheel will move 
>> both in and out freely.
>>
>> So the pole dewires, the catcher stops it with the top of the pole 
>> 3-feet above wire height, the pole hits the next span which, low and 
>> behold, pushes the pole down which is same as taking the pressure off 
>> the rope and crescent lever so the wind-up spring winds rope in and 
>> crescent lever resets in holding pattern allowing free upward 
>> movement of the trolley pole again. As the pole slides off the span 
>> it starts up rapidly which then activates the crescent which then 
>> stops the pole with the top above wire height. Rarely does the 
>> catcher hold the pole below wire height. It is possible but this is 
>> usually the result of the pole slamming hard against a span with a 
>> good bit of forward momentum to the car which then causes the trolley 
>> pole to descend well below wire height -- Then the catcher can catch 
>> the pole below wire height and hold it there -- the uninitiated will 
>> then say the pole was retrieved but This Is Not The Case.
>>
>>
>> Egg--Zample::::::: Riding early morning 38-Mt.Lebanon Inbound with 
>> Isadore Reichert. After crossing the Palm Garden Trestle we hit the 
>> prw which is gentle downgrade at first with very gentle right curve. 
>> We then start modestly upgrade, go through a road crossing from the 
>> lower buildings, then into a sharper right turn with storage tracks 
>> of PCCs on either side. I note a broken hanger whose ear has 
>> obstructed the trolley wire on this sharper turn and sure enough, the 
>> pole dewires. I tell Izzy but he says: ""Doubt the broken hanger; 
>> just the way the car rocks and rolls here.""       Outbound Izzy 
>> confirms the broken hanger and calls it in but not before we witness 
>> a good 1601-City Car at speed 3-4 times of ours hit the hanger and 
>> dewire. He traveled almost 6- car lengths modestly upgrade before 
>> getting the car stopped and that pole was above wire height and had 
>> smacked into Quite A Few Spans in the process. NO damage to pole nor 
>> overhead. Pole put back on overhead and off he goes. Didn't even 
>> knock the ear loose from under the contact wire!
>>
>> Dewirements like this on TrolleyCars in SF in the 1970s were 
>> Multiples of Times Daily -- No wire damage. Terrible Trolleywire here 
>> in SF then. Trolley coach is a different story because the swivel 
>> shoe allows it to snag in something Much More Easily even though 
>> controlled by retrievers instead of catchers.
>>
>> Believe it was pantographs causing derailments on PCCs in the Burgher 
>> after they were pan equipped! Yupp ---- you read that correctly. Pans 
>> don't dewire so operators were whipping it through turns Much Faster 
>> than they should have causing dewirements -- witnessed this 
>> personally at Wash.Jct. and, sorry to say, but believe many of the 
>> derailments at the turning loop here was speed through the trailing 
>> turnout because of pantographs -- trolley poles would force slower 
>> operation because the operator thought the pole would dewire -- with 
>> pans it is the trucks derailing. Another case for maintaining the 
>> Trolley Pole :-) ;-) :-D
>>
>> Trolley Pole damage is Much More Likely to occur in backing maneuvers 
>> although damage to poles can not be ruled out from forward movements, 
>> but I have never witnessed such.
>>
>> Everything has its positives and negatives. Not really worried about 
>> power draw with light rail so that advantage of pans is ruled out. 
>> Pans fail witness your URL below and poles dewire.       Simple to 
>> rewire a pole but not so with a pan.
>>
>> I have always been Ultra Fascinated with Trolley Poles, Overhead 
>> wire, wheels, flanges, and track work. I am strictly a trolley pole 
>> person personally and for my model work, pantograph equipped models 
>> Shall Not Be Allowed On The Property For Any Reason, NOT EVEN to set 
>> a pan equipped car on the tracks for pictures -- NOT EVEN ---- 
>> TROLLEY___POLE___ONLY.
>>
>>
>> Jim
>