Air Brakes on 1600 B-2s and B-3s

[Jim Holland]

Greetings!

	For most of the air-electric cars, air pressure applied the friction
brake and a spring released it.  This was apparently reversed on the
1200s where a spring applied it and air released the brakes, not unlike
the all-electrics where springs applied the brake and energizing the
solenoid would release the brakes.

	Which way did the brakes work on the 1600s?
	The reason I ask is that the experimental B-3 trucks were first tried
out under 1230 and 1278.  Thus, did the 16s have spring applied,
air-released brakes?

	Also, on the 1600 City Cars with Clark B-2 trucks, whatever apparatus
is needed to operate the friction brake on the drive shaft was mounted
internally on the truck - nothing is visible from the outside.  But on
the interurban 16s St. Louis B-3s, there was a large air cylinder
mounted on the spring side of the motor mount arm, much like the
solenoid on the all-electric PCCs.  Why the difference?  Why weren't the
actuators for the friction brakes mounted internally on the B-3s under
the 16s?

James B. Holland
------- -- ---------
        Pittsburgh Railways Company (PRCo), June of 1949 -- June of 1953
    To e-mail *privately,* please click here: mailto:pghpcc at pacbell.net
N.M.R.A.  Life member #2190; http://www.mcs.net:80/~weyand/nmra/