[PRCo] Re: B-3 truck development

Fri Apr 7 10:18:06 EDT 2006

Very  Nice  Summary!

This sounds like there were  Only  Two  Sets  of  Experimental  B3  
<--Frames-->  which were used under Two 1200s And Under 1613 and 1614    
----    obviously Not At The Same Time!!!       These two Sets Of Frames 
had a variety of  'Upper Frame'  amenities which started with double 
spring pots under the 1200s which were reduced to single pots under 1613 
and 1614.

You say:::::::       """There are photos showing the trucks for 1614 
nearly ready for fitting in August 1945."""       Did you mean August of 
1946?       1614 was not converted to Interurban until  1946.05.20.

The ERA publication of July-1952 on PRCo Interurbans indicate that PCC 
1613 was pulled from Craft,  """In January 1946....    had some weight 
applied to its  [B2]  trucks and became the first experimental PCC 
interurban car."""       Early photos Clearly Reveal B2 trucks under 
1613.       The article goes on to say  (pg.06):::     """The next month 
special St. Louis-built trucks, which had earlier been applied to PCC 
car 1278 for use on Rt. 37 Shannon, were rebuilt and applied to 
1613."""       AhhhhhHaaaaa!       We know a little more about 1278  (GE 
car invades South Hills  --  Yuck!!!!!!!)

Wheel usage was experimental for a reason but wouldn't consider it 
germane to the truck design itself.

If we consider 3-prototype  <--Configurations-->

++   Double Spring Pot Upper frame ala B1 with
                integrated motor support.

++   Double Spring Pot Upper Frame ala B1 with
                Separate Motor Support.

++   Single Spring Pot, Separate Motor Support

Then types of springing  --  rubber, conical, combo, etc.  --  are 
subsets of above.

Seems like type of friction brake would be a major design difference as 
well.

Bolster Safety Links  --  Finger Dampers?       Weren't these present on 
the production units Even When an external auto type shock was installed?

Boris Cefer wrote:
.

> The B-3 truck story is very interesting and there was far more 
> hanky-panky than we realized before. And of course, there are also 
> some facts still hidden to us.
>
> The company built two prototypes, one in 1940 (truck "A" for future 
> reference) and the other in 1941 (truck "B"). The dates given by Jim 
> Holland are probably correct, but it is not clear when they were 
> installed if these are dates of shipping.
>
> Truck A was the one which copied upper frame design of B-1 truck and 
> had conical rubber ssprings, superresilient wheels and tread brakes.
> Truck B had separate motor transoms, bolster with swinging double 
> spring pots, standard wheels and gear-mounted drum brakes. The 
> suspension was made by means of concentric coil springs, the outer 
> ones being right-hand wound.
>
> On truck A, the rubber springs probably did not work satisfactorily 
> and were soon replaced by steel coil and rubber combination (car 1225 
> photographed in August 1941). It is not clear, but perhaps at the same 
> time the motors were removed from the upper frame and suspended from 
> independed (resilient) transoms similarly to truck B. Diffucult to say 
> how long this version was in service.
>
> Truck B was probably more satisfactory, but the swinging bolster pots 
> caused problems with riding quality. A new, solid bolster was created 
> and substituted for the original. At the same time or shortly after, 
> four Houdaille shock absorbers were attached to the bolster to dampen 
> vertical motions. It appears that trucks of this type were tested 
> under car 1230.
>
> Now we are getting back to the A truck. The design with upper frame 
> was not considered good or satisfactory and it was perhaps too 
> complicated. It was sent to the company for rebuilding. The upper 
> frame and steel coil and rubber combination springs were removed. The 
> original swinging bolster from truck B was installed together with 
> coil springs wound left-hand (bottom photo page 132 PCC Fought Back). 
> Tread brakes were replaced by gear-mounted drum brakes. At the same 
> time or later NACO wheels were substituted for superresilient wheels 
> and two Houdaille shock absorbers added to the bolster.
>
> Now there were two very similar trucks (pairs of trucks), but one with 
> a swinging bolster pots. There was probably certain testing which 
> showed the solid bolster design better, but still a very complicated 
> design. A decision was made to simplify the trucks and the new 
> bolsters had single spring pots, like all mass-production units. Some 
> parts were salvaged and other parts newly built, but after rebuilding, 
> the trucks from 1230 went under 1614 (with standard wheels) and the 
> other pair under 1613 (with superresilient wheels and three Houdaille 
> shock absorbers on the bolster - one for horizontal and two for 
> vertical dampening). There are photos showing the trucks for 1614 
> nearly ready for fitting in August 1945.
>
> It is not know whether the superresilient wheels under 1613 did not 
> work satisfactorily, but they were replaced with NACO wheels later. 
> Also the bolster safety links were removed and two automotive shock 
> absorbers installed (two Houdaille shock absorbers removed).
>
> B

Jim__Holland

I__Like__Ike.......And__PCCs!!

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