Steam & Excursion > Not The Usual Appliance For This Engine But The Law Is The Law!

Even though photos of the fireman's side of Shay locomotives are somewhat rare, this one is quite rare for a number of reasons.

First, the fact that a Shay would be on the roster of the Union Pacific makes this huge geared engine stand out in it's own right.  But look closer and you will see the real oddity here.  Yes, that is in fact a power reverser mounted on the frame just ahead of the cab of this beast.

You may ask, how and why did the UP go to such an effort to install this power reverser on the engine.  Well the "why" is because that was the law as of the date of this photo in 1948,  According to the copy of the Locomotive Inspection Law dated 1947, all steam locomotives constructed after September 1, 1937 were required to have a power reverse gear. On road locomotives built prior to Sept. 1, 1937 with more than 150,000 lbs on the drivers or switching locomotives with more than 130,000 lbs on the drivers shall have a power reverse applied during class 1 or class 2 repairs. The install shall be applied by Sept 1, 1942.

This big Shay was built by Lima in 1907 for use on the Tintic Branch in Utah.  She weighed 135,500 pounds empty.  Because of her weight, she fell under the power reverse requirement. 

As to the "how" did they make the power reverse work, that is something else of interest.  As we know, the engine and valves are all on the engineer's side of Shays.  With the power reverser mounted on the fireman's side this posed a problem.  The controls for the engineer had to have a rod connecting them to the reverser unit by passing in front of the boiler backhead in the cab and out the fireman's side.  The reverser lever to the valve links had to be connected to a similar rod that passed back under the cab and frame to the engine unit on the engineer's side.  Not an easy application!

This big engine was later sold to the Oregon-American Lumber Co. at Vernonia, Oregon.  She kept her power reverser there until she was finally cut up in the 1950's.  The loggers that ran her there must have loved the luxury of the power reverser!


Martin



Edited 4 time(s). Last edit at 05/28/15 05:05 by LoggerHogger.

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Is that a power reverse?

Sure looks like it would be one, but pretty odd looking!

RRMike Wrote:
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> Is that a power reverse?

Perhaps reading the text that Mr. Hansen included in this post would answer your question.



Edited 1 time(s). Last edit at 05/28/15 06:47 by mikeman.

Western Maryland #6 has a power reverse.  As it was installed by Lima it is in a more normal location, under the cab - actually under the coal bunker.

West Virginia Pulp & Paper (Cass) had a power reverse installed on Shay #5 to comply with the requirement for a switch engine.  It was used on the Western Maryland controlled former GC&E line on the Cheat River.  The power reverse stayed on the engine into the Cass Scenic RR era and was finally removed in the 1980's.  What is interesting is that WVP&P/GC&E #12 was a huge 150 ton 3 truck that became an even bigger 4-truck machine that would have come under the requirements for a power reverse, but never had one put on her.

BTW, #5's power reverse was installed on the right side ahead of the cylinders above the running board.

Mower #12, ex-GC&E #12, was wrecked in December 1942, a few months after the deadline for installing a power reverse.  As a three truck shay the brake cylinder for the third truck was actually mounted under the coal bunker.  When it was converted to a four trucker, the brake cylinder was removed but the mounting pad was left.  This would have been a logical location for mounting a power reverse, had it continued to operate.

Michael Allen

Great picture and story
Luke

Posted from Android

From a post about three years ago...

http://www.trainorders.com/discussion/read.php?10,2665356

Posted from iPhone

I'll ask the obvious question (speaking for myself and others not aware of the details), but I presume that a power reverse uses steam to move levers that put the engine into reverse. Otherwise it would be brute force applied by the engineer to reverse the drivers. Is that correct?

Correct.  In a conventional engine, the reverse lever (Johnson bar) moves either a die block or the links, depending on the type of valve gear.  This can involve some considerable force.  In a Shay, the links are horizontal and are shifted laterally, so it takes a lot less force to reverse a Shay.  Unless required by the ICC, I doubt if any Shays were built or converted to power reverse.

Michael Allen

The ICC got involved because of the safety factor.  The old 'Johnson Bar' was directly connected to the valve gear, and when using it to change positions of the gear ('Hooking up') when you pulled the latch and released the pawl out of the sector that held the lever's position, you were holding the entire force of the valve gear train in your hands.  Old books mention that some hoggers ended up being thrown/pinned against the front or back wall of the cab when doing this.

The steam cylinder acted as a 'servo' where a small amount of input from the engineman moved a pilot valve that used steam turret pressure applied against the area of the piston in the reverse gear cylinder to move the valve gear linkage, isolating him from a flailing lever.

There were several types of operators, probably the most popular was the Baker type that was basically a miniature Johnson Bar quadrant with latching lever.  You can see this type on C&O 2-6-6-6's.

Probably the least popular (when switching, at least) was the Franklin precision screw reverse that used a wheel that ran through probably 8 turns from forward to reverse.  Nice when running, but tiring when switching.

A classic story about the screw reverse was told by the author of 'Firing on the Pennsy' (a wonderful book, by the way).  A hogger noticed that a green brakeman was watching his every move and when he started down Wooster (OH) hill, he was moving the screw wheel back and forth a little bit, as if he was steering the engine.  He stood up and told the greenhorn "Take over Brakie!  I gotta go water the coal pile!"  

When he returned the brakeman was sitting on the right side diligently using the reverse wheel to keep the train centered on the track...

Power reverse is normally operated by compressed air, not steam though there may be a cutover valve to allow steam to be used in an emergency when air fails.

PorterNo2 Wrote:
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> From a post about three years ago...
>
> http://www.trainorders.com/discussion/read.php?10,
> 2665356
>

Here is the note I created, based on the helpful comments from that original question three years ago.

http://www.utahrails.net/up-steam-roster/steam-roster-notes.php#powerreverse

Don Strack

To fill in the details, here are a couple screen caprtures of a much larger drawing that shows the complete arrangement for a power reverse for UP Shay no. 61.

Don Strack

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