Locomotive Improvements and Others, Mt. Washington Cog Railway

It had been over 35 years since I last visited the Mt. Washington Cog Railway, so I was pleased to make another pilgrimage this past September 24th. Mt. Washington is known as the place with the worst weather in the lower 48 - but this day was clear and pleasantly warm, without the blizzard which I had expected at the top (having found one waiting for me on my last visit).

The Cog isn't as rickety and rustic as I remembered it. Base Station as I knew it burned down some years ago, and has been replaced with a much nicer facility with lots of indoor plumbing, food service, and an interpretive museum section on the ground floor. Some sectioned and disassembled rolling stock and a video loop provides visitors with a lot of technical and historic insight into the railway and how it works. 

The top house has also been replaced - I recall an old wooden building chained to the granite of the mountain to prevent its being blown off in winter storms. It must have blown down, because a much more substantial concrete structure has taken its place, with all the comfort facilities a visitor could want no matter what the weather.

Cog train at the top.  All photos by Dave Lathrop.

Considerable track and ROW work was evident on the trip up and down. A passing siding was being installed, a new water tank has been put in, and considerable other attention paid to the permanent way. On the way up we passed a work train powered by #9, WAUMBEK, on the finished portion of the passing track. I later learned that #9 was in fact "The Victim", as the shop crew refers to the locomotive on which experimental alterations and improvements are being tried under the direction of Mr. Nigel Day (formerly with the Snowden Mountain Railway in Wales).

Upon reaching the bottom, I tracked down Mr. Day in the company offices, and he was kind enough to take an hour out of his day to show me around the enginehouse and shops, and give me a firsthand account of the modifications he was working out on The Victim. 

Nigel Day and "The Victim".

Mr. Day is a gentleman with a quiet, soft-spoken, unassuming manner who has taught himself steam engineering from the shop floor up. What he knows he knows from hands on experience, as well as from books, and working with other British engineers. He did some improvements at Snowden, and is pleased to have been given the freedom to continue to work on improvements at The Cog, where his practical ability to put his theoretical ideas into practice is supported by Al LaPrade, and a highly qualified shop staff. 

A little technical stuff about the Cog lokies - they are unique. No other cog or standard railway uses power like those used by the independent New Hampshiremen. They were developed and home built specifically for their purpose, and the basic design hasn't changed much in the past century. They have no reversible valve gear or variable cutoff.  If any force apart from gravity is required to reverse, a series of valves is used to reverse the flow of steam through the cylinders and piston valves (the steam and exhaust lines essentially replace each other). The piping lengths and diameters and complexities of this arrangement have combined to produce some inefficiencies in the steam flow, one result of which has been the addition of a "side stack" to exhaust part of the spent steam, and thereby reduce back pressure during operation. This diverts part of the exhaust steam through a separate pipe rather than through the nozzle and up the stack. 

Traditionally, a self cleaning front end was used to eject the unconsumed products of the coal fire with the portion of the exhaust steam used to create draft, but environmental concerns and potential for brushfires are now under consideration. Braking is by compression and hand brake. A sprag ratchets into the rack to prevent potential runaways on the way uphill. It has been known to happen for both engines (4 cylinders operating two separate crank axles) to halt on dead center with the weight of the engine on the sprag, and the locomotive therefore unable to start forward or slip back to start the train, without the engineer climbing under the frame to shift the eccentrics a bit or to jack the whole thing forward.

These are some of the operating issues Mr. Day and the shop staff are working to improve. Coming from Wales, Mr. Day is committed to making improvements not only for practical operating reasons, but to also provide a good defense by making a first offense against the foreseeable actions of environmentalists who may find coal fired steam locomotives a politically feasible target, despite the fraction of a pittance of a part of a percent of all pollution created by every coal burning locomotive in the world combined. It seems that parts of Wales reflect Californians in Colorado in that regard.

Specifics about the improvements - it is not my intention to get too deeply into his work in this article. Many people more qualified than myself to do so, regularly post to the SteamTech list and to Hugh Odom's ULTIMATE STEAM PAGE. I offer here a basic overview of some of the modifications he has made to The Victim, and the results of his actions so far. 

1. Firing practices - our conductor informed us that his fireman shoveled one scoop of coal every ten seconds with one arm on the trip uphill. I certainly hope not. Bear in mind, the conductor hits up the riders for tips for the crew at the end of the trip, so it behooves him to magnify the work of the crew. Whatever the firing rate has traditionally been, it did exceed the capability of the grate to burn the fired coal, and a lot of wasted fuel resulted. Firing is now to be done at no more than required with an ultimate limitation of grate capacity. 

2. Combustion air flow - The Victim has been equipped with a damper and a Lempor exhaust system, and had its self cleaning capacity removed. In the photos below you can see the traditional design (less baffles, petticoat, etc) in the #10 undergoing heavy boiler repair in the shop, and contrast it to the Lempor in The Victim. The Lempor must be engineered to suit the specific application, and consists of more than just the nozzle - there is a venturi-like thing fabricated and fit into the old style stack. The Cog doesn't want its engines to change much in historic appearance. 

Original exhaust design (above), Lempor exhaust (below).

3. Feedwater heater - the steam which would be exhausted through the side stack is now diverted through two heat exchangers before being exhausted. Water from the tank is heated by this exhausted steam, and is brought up to a couple degrees below the temperature of the superheated water at the boiler pressure before being pumped into the boiler by an axle driven pump. A bypass valve regulates the quantity of feedwater which passes through the checks. Bypassed water returns to the tank. 

Axle driven pump (above), heat exchangers (below).

4. Automatic safety brake - this replaces the sprags. This massive disk brake automatically releases when the throttle is opened, and applies when it is shut on the uphill trip. The engineer can control its application on downhill trips. He can also ease it back a bit to get off dead center if necessary. This alteration has not yet been installed. 

Al LaPrade working on new disk brake.

In aggregate, the modifications listed here have reduced fuel consumption on The Victim by 50% relative to the unmodified locomotives. Halving your fuel consumption also halves your pollutants. Cinders and ash no longer are ejected from the smokebox, but are collected from the front end at the shops at the end of the day, thus also controlling those potential environmental concerns. 

What's next? Mr. Day is committed to continue to work on improvements to the combustion and steam flow engineering as long as The Cog will allow him to do so, as well as continue to make a greener steam locomotive both fiscally and environmentally. The Cog is continuing to make other infrastructure and track improvements as well, and plans their first winter operations this year. The staff, to a man, referred to starting winter trains as a "learning experience" waiting to happen - hopefully, they will share those lessons and some impressive images of steam in snow on The Cog as well.

(Dave Lathrop)