Steam & Excursion > Send engine for big job.

A little engine, that is. T&P had some small 0-6-0's and some larger USRA 0-6-0's but still, they were little compared to other engines. One of the USRA's was sent up the 1% hill from Lancaster yard to pick up engines in the Ft Worth passenger terminal. Here it is shown tied on to an 0-8-0 and two 4-8-2's. Getting all that started had to be fun but I imagine not more so than controlling them back to the engine terminal about 2.5 miles down hill.

Question to steam people familiar with engine brakes. Could you cut out the independent brakes of the engines and use their brakes as "train" brakes?

I assume you could but, still would have to be careful.



Edited 2 time(s). Last edit at 07/20/17 13:30 by tomstp.

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I greatly enjoy all your informative posts re: the T&P, a railroad about which I don't know much. You generally don't identify the photographer. Is it you?

Could you cut out the independent brakes
> of the engines and use their brakes as "train"
> brakes?

I'm no expert, but have some experience.....

You'd be safest, by having at least 1 air compressor ( per towed engine) operational...in the pictures, .it appears that they are 'live', --- at least to some extent....that way you'd have air for operating the brake cylinders.

The Automatic brake valve handles, on each of the towed engines, must have the double-heading cock turned to cut-off the brake stands from affecting the
trainline brake pipe pressure. The independent brake handles, on the towed engines, should be placed in 'Running' position, meaning that the brake cylinders are not pressurized from the Independent brake valve, at the switcher engineer's position.

The switcher's Trainline pressure regulator ( brake pipe 'Feed Valve") should be adjusted to the nominal, "Passenger Service", brake pipe pressure: 110 PSI.
[ in 'freight service' , the nominal BP pressure is 70 PSI, depending on the RR's standard operating practice..].

Then the towed engines should have their trainline hoses all connected, the angle cocks opened ( except, 'closed' at each end of the train).
The main reservoirs are charged by the towed engines' compressors, and the brakes, on the towed engines, should be applied and released by the engineer's Automatic brake valve, on the switcher.

The towing engine's independent brake will only operate the switcher's brakes.
To apply and release the towed engines' brakes, the engineer would use the Automatic brake handle.
However, the common-standard brake valve at the time, was the schedule 6ET, using a 'distribution valve' to actually control the engine brakes.

Typically, the most responsive loco control of the engine brakes.
The engine brakes will also be applied by the Automatic Brake valve, and its regulation of trainline pressure.
When the engineer applies the Automatic brakes, the distribution valve ( 'service portion ) reacts to the reduced pressure to also apply the engine brakes...

Generally, the engineer, uses the independent brake valve ( on the single engine) to release the pressure in the brake cylinders, independently of the Automatic brake's function
and it's possible application of the driver brakes on the towed engines.

Sooo. If the boilers and air compressors ( on the towed engines) can maintain Main Reservoir pressure
( the source of compressed air for applying the locos' brakes), then the brakes can be applied and released by the Automatic brake valve on the controlling loco.
The towed-loco brakes are now operated as conventional car's brake control valves....

[ However, the designers of the 6-Brake, realized that having the loco brakes react similar to car brakes ( very sensitive), would have the heavy engine brake's battering the towed cars around during normal brake applications. Soooo, the designers added built-in 'restricting orifices' to 'de-sensitize'. The driver brakes on the locomotives.....Thus, when handling these towed locos, the switcher engineer would have to make heavier brake reductions on his Automatic valve to get the brakes to 'come on' at the towed locos.]

And yes, before departing from the terminal to the roundhouse, full brake tests and functional inspections should be performed, setting and releasing the brakes on the stationary locos ( from the switcher) before moving, and then followed by a "test-application", once underway ( a "set & release").


So, with the engine's in tow, cylinder cocks open, and reversers 'centered', you could move the locos.

The mass of the towed engines would easily over-power the small braking power of the three-axle switcher....yes you cold stop the Drivers of the switcher from turnin, but if would then slide, along the rails..possibly creating dangerous flat-spots on the switcher drivers.....

Hope this helps...

W.

An alternative, would be to drive the "whole shebang", from one of the big engines, with the fireman( ?) on the switcher...drive the bunch to the roundhouse ...
Probably, safer, too.



Edited 1 time(s). Last edit at 07/20/17 17:16 by wcamp1472.

Thanks Wes.

Very cool photo! Plus very interesting reply. I was wondering if there might have been some more crew members available (back then), to man the other loco or locos, and apply brakes when needed? Nowdays we are used to assuming there may be only one crew, in the work engine only, but maybe, back then, they may have had enough folks to man the other towed engines too?

Jim Baker
Riverside, CA