Cass Scenic Railroad, West Virginia

It's June 2017: I've been to the USA again and found another spectacular steam railway. I have to admit that I like the American Olde Steamy railroads. They seem to do higher, steeper and/or longer than we do in the UK; some to a massive extent and Cass Scenic Railroad is one of these.

I've visited the Cumbres and Toltec, Durango and Silverton, Georgetown Loop, Mount Rainier and a few others before. Cass was new to me and what a gem. It's steepest gradient is 11% or 1 in 9.09 and, according to wikipedia, is the third steepest non-rack railway in the world.

Cass is the home for Shay locomotives. Like Joyce (there is a connection), Shays are geared locomotives and they don't go fast. They are designed for steep gradients, sharp curves and poor track as built for logging railroads in the last century or earlier. Cass has about five operational Shays plus a Heisler and a Climax although not all in workable condition.

So what's a Shay?

Shay No. 2 at Bald Knob Summit

Shays have a three cylinder vertical steam engine along the right hand side. The engine drives a flexible shaft which powers all axles using a ~2:1 bevel gear mechanism. To counteract the weight of the side-mounted engines, the boiler is offset to the left of the chassis; I wouldn't describe this as an elegant feature but it probably prevents a lot of toppling accidents.

Three cylinder vertical engine

Three cylinder vertical engine with air brake pump in the foreground.
Driveshafts are below.

Like Joyce, the engines revolve quite fast and produce a purr rather than a chuff when in motion. A variable length drive shaft with gimbal bearings enables the drive to reach the axles whilst also being able to negotiate sharp curves and undulating track. Bevel gears provide the 2:1 gear reduction.

Drive shaft with gimbal bearing and square variable length shaft joint

Other end of above drive shaft

2:1 Bevel gearing to axles

All the action is on the right hand side. Although one-sided, it does make preparation easier by avoiding the need for access to both sides.

RHS Action Packed side

LHS not so populated

Cass Scenic Railroad is steep. It runs for 11 miles to a height of 4842 feet through some of the most spectacular forestry locations. It also has a zig-zag.

Route from Cass to Bald Knob summit

There is an extensive loco fleet, definitely not of the conventional type.

Loco Fleet

Trains arrive loco-first from the yard to depart propelled from the 'Depot' at Cass.

Arriving at the 'Depot'

Video clip is here on YouTube (including bells & whistles).
The train propels the carriages (cars) from the depot up to the summit except in the zig-zag.

Departing from the depot.

Video clip is here on YouTube (including bell but no whistles).
The train passes this location by the maintenance shed.

Running line leftmost

It begins the ascent and approaches a level crossing. Note that, in the USA, heavy use is made of the whistle when approaching a hazard. (Memo to me: must get one like this for Joyce).

Crossing approach

Being a propelled train, it's possible to book to be in the carriage adjacent to the smoke stack. Whilst this seems like an enthusiasts' heaven, the smoke stack is extremely loud. Many passengers use ear defenders and I'd very much recommend this as 2-3 hours of the noise is somewhat fatiguing and it also drowns the informative commentary.
Video clip is here on YouTube (including whistles galore but no bells).

Cass Level Crossing

A second video clip is here on YouTube (including whistles galore, no bells but many birds).
The line climbs up the hillside.

Line fades away behind

Video clip is here on YouTube (including no bells, whistles or birds but the gentle purring of the fast revving steam engine).

Onwards and Upwards

To gain height in a short distance, the Cass railroad has a zig-zag. I've tried to capture the gradients encountered.
Video clip on YouTube of the train arriving at the zig (including no special sounds).

Line climbing to meet the zig-zag middle section

Video clip of Shay setting off hauling the train up the middle section of the zig-zag (sounds different hauling in reverse).

The train approaches the down-coming train waiting on the top section of the zig-zag.

Down train ahead on left

Video clip on YouTube of the train meeting the down train.
The up train goes into a long spur and waits while the down train follows into the spur. The down train then reverses out and down the zig; the up train then reverses out and up the zag.

The line climbs onwards to the summit at Bald Knob (4842 feet) through some amazing countryside.

Almost at the summit

Shay No. 2 at the Bald Knob summit

View backwards from whence we came

Finally, Shay No. 2 descends somewhat more quietly than when climbing (including not much noise at all!).

A fantastic 5 hour journey, one of the best there is.

Mount Rainier Scenic Railroad

So what has this to do with Sentinel 7109, I hear you ask! Well not an immediately obvious lot except that on my travels to Washington State USA in July 2011, I landed almost accidentally on the Mount Rainier Scenic Railroad. Not expecting too much to begin with, I was pleased to be cordially invited to visit the 'shops' and see the steam locos not in use at the time.

I was stunned to be presented there with a Heisler, a Climax and a Willamette - all in working order. A Shay under restoration was also there in the shed.

On returning home, the photos I'd taken in the 'shops'' shed (yes, the apostrophes are correct; a quote of a genitive plural!) were far from as good as I'd hoped. However, here are some of the best ones.

Willamette 34

Not a Shay

The less mechanical side

Leading drive-train

Trailing and tender drive-train

And finally, the Climax!

Having had a good look around the Mount Rainier Scenic Railroad website, I can't come close to their pictures. Try these:

Heisler, Climax, Willamette (On the right).

Have a look around the Gallery; it's a superb collection of photos of Steam Logging locos.

Meanwhile, Sentinel 7109's whistle has featured prominently during its refurbishment. Strange noises from my garage have kept the neighbours bemused for hours (well, minutes anyway). So if Midsomer Norton station can manage to replace its missing Silver Street bridge with a level crossing, how about if we upgrade 7109's whistle and blow it like this to frighten the traffic away! (Also on YouTube)

Whistling in the USA!

The culprit in the video: July 29th 2011,
MRSR's newly restored Baldwin 2-8-2 Rod Locomotive
No 70, Polson Logging, near Elbe, Washington State, USA.

And after all that, there is a connection with Sentinel 7109 - it is also a gear driven locomotive!

Sentinel 7109's whistle valve and how does it work?

A peculiar looking valve had been hanging around Sentinel 7109's stores looking for a use. Eventually, I was advised that it was a whistle valve.

Grubby looking thing!

Alternative view

With mounting flange and whistle-mounting elbow

Whistle valve roof-mounted in Isebrook

Whistle valve roof-mounted in William

Unlike Isebrook and William, Sentinel 7109 has the whistle and valve mounted vertically on the cab front.

Front-mounted whistle (the valve is inside)

So how does a whistle valve work and how does it enable the 'pop' action needed for the whistle?

Functional Parts

The main valve body allows steam in through the top right connection where the air-hose adaptor is shown here. The steam is held back by a conical valve pressed against a valve seat by a spring and also by the steam pressure.

Conical valve (not to scale!)

Valve seat inside end of valve body

Spring and retainer which screws into the end of the valve body

A rod passes through the valve body and rests against the conical valve's base. To sound the whistle, the conical valve is pushed off its seat by the operating lever's movement which pushes the rod against the conical valve's base.

Rod (not much more to say on this!)

Operating lever

The steam can then pass out to the whistle through an aperture in the valve body's flange.
The steam pressure holds the conical valve in place until the lever is used to push it open. This is a sudden action which is also terminated abruptly by the steam forcing the conical valve shut again. Hence the whistle valve enables a quick 'pop' to be achieved as well as the long 'poop'! 

There is one more aperture in the valve body shown with a copper tube attached in the Isebrook valve picture (but, oddly, not on William).

Condensate drain

As a result of the whistle being sounded only occasionally (hopefully), the valve body will generally be cold when steam is admitted. Thus the copper drain tube is added to allow the resulting condensate to be drained away.

When it's all assembled, it looks like this.

Note the elegant MDF cab front substitute and supporting clothes' peg!

Finally, when I first took the valve apart originally for renovation, the conical valve seemed to have a leathery pad between it and the seat. As the pad was in an 'aged' condition, I discarded it wondering where to find a replacement. On subsequent closer examination, it looked as if the conical valve and seat were both in good condition and, after a small amount of regrinding, were clearly perfectly satisfactory. Thus I concluded that either the leathery pad was accumulated muck or was a misguided bodge from the past! Who knows? But it isn't there now!

Clean as a Whistle!

When Sentinel 7109 was originally brought to Midsomer Norton Station in December 2004, its whistle was missing. From early pictures of 7109 in service, a tall thin item was required as a replacement.

Tall thin whistle 1

Tall thin whistle 2

Other Sentinel locos seem to have a variety of whistles such as William's but something more authentic to the original was wanted.

William's proud possession

Early July 2011, the ideal thing came up on Ebay and I was the only bidder! Although its fittings were not quite suitable, it seemed as good as was likely to be found (another was offered for £350 which was declined rapidly!).

On arrival, it was tarnished but in good working order and a definite possibility.

Clearly, it once had a sticky label attached

Gun-metal mounting and steam inlet to the left

It's such a simple, passive device, I'm sure I could have made one!

Cap machined from solid gun-metal

To clean off the tarnish, I used a phosphoric acid gel originally used for derusting car bodywork. Finally it was brightened-up by Brillo pad and a french polishing technique known as grisse d'elbeaux.

Shiny and clean as a whistle!

Some say (where've I heard that before?) that the whistle looks like one from an 08 diesel-electric shunter. I checked this out in Brian Haresnape's British Rail Fleet Survey "7 Diesel Shunters". It appears that 08s did have this type but they also had a number of others and horns too. As Sentinels also had this type and others, I'm sure this whistle will do just fine!

Despite many attempts at testing the whistle with compressed air, my neighbours are still talking to me. However, when I put the video below together, it frightened the hell out of the local cats and the next-door dog had a fit!

(Note: I've sometimes had trouble playing the video repeatedly. If this is the case, reload the window (F5 on PCs) and try again). Alternatively, it's here on YouTube.