[PRCo] Re: Pittsburgh 1200 models

Mon Apr 3 21:14:43 EDT 2006

I believe that Boris provided us with this photo of the 1200 truck and 
brake system:::::::

http://lists.dementia.org/files/pittsburgh-railways/1200s%20brake.jpg

Assume that lever near the bottom right which runs toward the cylinder 
near the upper left is the one that is pulled to release the brake    
----    also assume that this must be done on each axle.       That 
lever is right behind the tube frame so the Operator // Mechanic would 
need to kneel on the street, reach behind the wheel  (in front of wheel 
on the other side of same truck for other lever)  to pull for the 
release.       Not the same as actually crawling underneath but if the 
car moved and one didn't react accordingly there would be Real Potential 
for disaster!

The B3 is basically a spring applied // Electrically released drum  (air 
release on PRCo 1601-series Interurbans)    ----    Maybe That Is The 
Reason that the first two sets of Eggsperimental  B3  trucks were tried 
under the 1200s  which were spring applied as well    ----    here is 
1225 sporting those trucks:::   http://206.103.49.193/pitts/htm/jfp073.htm

On the foldout in the back of  PCC  Car  Fought  Back  is a column 
after  Compressor  called  Brake  Valve.       A description of this 
item is Not included on the back page.       PRCo PCC Cars  100,  
1000--1199  used  R8;   1200--1299  Used  <R10;>      1400--1499 used 
R8B;     1500--1564  and 1601--1699  used  R12.       A quick review of 
All Operators reveals that  Only  PRCo 1200s  used  R10    ----    donut 
know if that is any indicator of spring applied // air-released or 
not.       Do  You  Remember???????!!!!!!! :-)

Not a few of the 1200s were converted to drums  --  this alone could 
cause some problems, esp. if the dynamic was Not extended for  (as You 
Know!!)  the drive shaft is moving 7.17 times faster than the axle  --  
Not as much force needed to hold the car once stopped but a spring 
actually stopping the car from 3-mph could be a little 
problematic.       The PCC book above mentioned, pg. 153, last 
paragiraffe states:::   """The only significant problem with the drum 
brake apparatus was a lower braking rate than with the air equipment 
which doubled the use of the track brakes...   [concern about drum 
<possibly>  causing jerky start mentioned as  <imagined.>]   ...The 
solution to the imagined problem, however, meant that the brake drums on 
the St. Louis car would not be effective in holding a fully loaded car 
on a grade steeper than 4.8%, which was in stark contrast to 16.8% 
grades with the Pittsburgh air-brake car."""       Development is 
Evolutionary and eventually this problem was overcome    ----    Boris 
also calculated that the 1700s with Spring Applied Drums were capable of 
stopping and holding a car on a grade well in excess of that on the 
21-Fineview and approaching that of the 16.8% figure  (that email is in 
Noah's Ark-Ives on this list!!!)       But lag time for spring action, 
weak spring, weak drums, whatever contributed to problem  --  ops were 
scared of the 12s.       Izzy Reichert had a 12 on the Dormont line and 
he really panicked when the car started to roll backward during braking 
UpHill!       Don't remember if it was wheel tread or drum  --  latter 
1950s.

Mentioned Before And Again Here    ----    Bob Rathke told us the story 
of the  PRMA  representative who arranged a charter for  N.M.R.A.  
convention in latter 1950s  --  Each Car Type including Interurbans was 
used  --  1200s, 1700s included.       Operations had a ban on drum cars 
as well as 1200s  (brake release for towing)  on 40 line and of course 
that is where they wanted to go to show off the city.       PRMA  rep 
went Straight To Palmer for approval which ticked off the shop but then 
possibly this action relaxed this ban  --  near the end, anything would 
go.       Not  At  All  Unusual  for operations to restrict equipment on 
certain routes to  Lower // Prevent  opportunities for problems    
----    For Many Years,  Only Baby Tens were allowed on the J-Church 
line in San Francisco  --  1101s were not used and the longer double end 
torpedoes were said not to clear.       Near the end of PCC service, 
anything which could operate was sent out on the J  --  One evening 
Operator Always had a long torpedo!!!!!!!

ALL  PRCo  Air-Electric  PCCs  were delivered with wheel tread brake 
shoes  Except  1601--1699  which were delivered with drums And extended 
range dynamics.       ALL  PRCo  Air-Electric  PCCs  were Air-Applied, 
spring released brakes except 1200--1299 which were just the 
reverse.       And  ALL  PRCo  Air-Electric  PCCs  did not have extended 
range dynamics, except the 1601s as already noted.       Pg.155 of 
aforementioned book states that 1443 experimental outfitted with 
extended range dynamics in 1943  --  some of the 14s also had dash 
mounted toggle for activating the track brake!       Book goes on to say 
that Westinghouse and GE rewired 13 cars from  BTC,  MBTA,  PTC,  PRCo,  
SLPS,  TTC,  and  DCT  for extended dynamic and most of the cars also 
received air-operated drums.       (Side Note  --  apparently 1413 was 
experimentally converted to All-Electric operation along with SLPS 1657  
--  pg.153.)

Fred Schneider wrote:
.

> I have a list somewhere ... probably filed away at PTM to get it out 
> of here...that listed all the brake variants on Pittsburgh PCC 
> cars.      If the 1200s had conventional dynamics and spring-applied 
> air-release tread brake shoes, it would have been logical to have some 
> very heavy springs to apply those shoes and use the air to graduate 
> the release of the brakes.
>
> I have a recollection that they rewired a lot of cars for extended 
> dynamic brakes and they might have done that to 1200s.       That 
> would create a whole new ball came, so to speak. You wouldn't need the 
> same force to apply brakes.       Just enough to hold the car.       
> And you wouldn't need to graduate the release because you would not 
> have time to do it because the brakes wouldn't come on until you're 
> down to 1 mph.
>
> If Ed can find the page in all the PCC back up crap......
>
> Holland Electric Rwy. Op. H.E.R.O. --  Import SPTC 1.48 Models // 
> James B. Holland wrote:
>
>> One would assume brakes were good upon purchase -- experience with 
>> 10s and 11s was probably quite positive but experience with 12s may 
>> have taught otherwise.       At delivery, 1200 series PCCs wheel 
>> tread brake shoes were <Spring__Applied> Air--Released ---- opposite 
>> of the Standard Of The Day!       To release the brakes for a Push / 
>> Tow job it was necessary to climb partway under the car ---- that 
>> also helped to ban the cars on lines with steeper grades.
>

Jim__Holland

I__Like__Ike.......And__PCCs!!

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