Monday 7 September 2020

16mm scale Hunslet ALICE

Here are just a few thoughts on running a 16mm Hunslet ‘Alice’ class locomotive. The loyalty this locomotive enjoys is based on the history of the prototype. It amply rewards its place on a 16mm layout.


The picture shows a Wrightscale Quarry Hunslet pushing slate wagons. Photo and layout by Malcolm Wright

Among the most celebrated Quarry Hunslets were those which served the quarries at Diorwic in Wales. The original quarries have served as inspiration for a number of super 16mm scale layouts, giving opportunities for a variety of situations.Strangely enough, they were dismissed as an industrial site during the lifetime of the quarries. Dinorwic never attracted the tourists who came to the Festiniog or the Talyllyn. The longer these quarries have been closed, the more intriguing they have become.

To us nowadays, an air of mystery hangs about Dinorwic. It is sited in North-West Wales, squeezed between Snowdonia, the lakes of Padarn and Peris and the Menai Straits. It has the most extraordinary and beautiful scenery and local folklore (last stand of the Giants, the Druids, the Welsh Bards). The English owners compounded the mystery of the Quarries with their family feuds involving racehorses and by deliberately destroying Company records. As an afterthought, bards and druids aside, it has to be added that the Quarries counted as outstanding both in longevity and mechanical innovation. JIC Boyd (Narrow Gauge Railwas Vol 3)

For centuries, slate had been used as a building material in North Wales. A 19th century diarist, Mr Ellis, remarks of one of the quarries that it was ‘an old quarry worked by the old people for hundreds of years’. The quarries of Dinorwic became a commercial proposition in the late 18th century because product could be taken to Llyn/Lake Padarn, thence by lighter to the nearest port. One village expanded from 13 households in 1785 to 140 by 1850 (Ellis again).

The Quarry Huslet adapts well to a more rural setting. 16mm scale Wrightscale Hunslet

Firstly, it is believed, there was a horse-drawn tramway. The word ‘legendary’ was used about it which is perhaps the wrong word. A legend is something written down and nothing first-hand remains about this. Between 1824 and 1843, a 24 ½ “ gauge railway ran 7 miles from quarry to lake. Because of sharp gradients, the wagons had to be hauled by cable part of the way. It was replaced by what was called the Padarn Railway though it came to be called the Dinorwic, begun 1841, closed 1961. This was 4’ gauge. 2’ gauge slate wagons were to be carried on special transporters. Quarries and railway were connected by cable-worked inclines.

We fast-forward to the 1870s. Down by the lake-shore, the quarries were served by a 4’ almost-standard gauge railway. Up in the quarries themselves, as railways developed there, 2’ gauge was more convenient. At first, horses provided the motive power, but as they quarried deeper into the mountain face, the advantages of locomotion became more apparent. These would have to be special. 2’ gauge locomotives would be virtually marooned up there although they did come down for major repairs (more below)..

Wanted! A locomotive tough enough to stay out of the workshop for long periods, small enough to be cable-hauled down where necessary and powerful enough to haul significant tonnages of slate and waste. Although the company loved a bargain as much as any, only three of the 31 they purchased were second-hand. A worn loco was a false economy.

A close-up view of this 16mm Quarry Hunslet shows how small and neat it is. Wrightscale model

In the 1870s, the company purchased some de Winton locomotives, but showed remarkable allegiance to one manufacturer – the Hunslet Engine Co Ltd of Leeds. Broadly speaking, they provided three types of loco: Port Class and Tramway which were both seen around the loading docks, the Alice which generally stayed in the high quarries.

Tramway and Port were supplied with cabs, steam domes and higher chimneys. The ‘Alice’locomotives which were destined for narrow slate galleries had neither cab nor steam dome. They catered neither for health, safety nor comfort. The lack of a steam dome gave them the look of the bogeyman in ‘Scream’ that celebrated image of alienation and fear.

In spite of or because of these peculiarities, they have proved to be the most loved of prototypes.

The Alice class was quite tiny and could turn, almost, on a sixpence  (2 ½ New Pence). They could negotiate a 21’  radius curve, roughly 6 ½ m. The frame was 11’6” long, with front and rear overhang of 4’. Those good at arithmetic will see that the wheelbase was less than 4’  (1.2m). Most stood 7’3” above the top of the rail – including chimney. You might assume that the other two were taller but in fact, KING OF THE SCARLETS and LADY MADCAP had even shorter chimneys. They were, to put it mildly, compact. Not all of them spent their lives in the upper quarries but they were well adapted to the high life.

Though the livery preferred by the Dinorwic Management was Midland Red, many prototypes were black.

Making a model of such a small prototype was a challenge and running one is a proof of the model engineer’s mettle. We are proud that, over the years, our customers have wanted the refined pleasures of lighting up ALICE (or, if you prefer, KING OF THE SCARLETS), ENID, or if you prefer, RED DAMSEL, CLOISTER and so on. 

True to prototype, they have a sharp sense of humour. The original Alice and Enid were members of the owner’s family. His son decided to rename them, and other Hunslets, after race-horses. The model ALICE is not above the odd prank. She shows when she is ready to run by ejecting hot oil and condensate from her chimney. Do not be kneeling within range!  As they are modelled on small prototypes, there is nowhere for the heat to go; once the locomotive is running, it gets quite hot. There will be cool spots on larger live steamers, but take nothing for granted with ALICE!

Yet once the locomotive is running, she has endurance and is actually easier to keep in steam than other models. This is true of he prototype. Boyd remarks that the non-Hunslets on site ‘certainly required more careful handling’or ‘though useful, lacked the quality of a Hunslet product of the same tonnage’ She is not a model to fear.

It is important to get to know your model before taking her out. (Good advice in any situation, I say.) She likes ritual. All preparation has to be done in order.

Looking into the open cab of a Wrightscale Hunslet from above, showing the lubricator (left side), gas filling valve, left of centre, regulator, central, gas control valve and water filler to the right.

Firstly fill with water. This should be distilled water or water recovered from a condenser-drier or dehumidifier. Use the syringe provided at water at around 70 degrees. Open the regulator slightly by turning anti-clockwise, or the water will bubble back, then inject into the water filler in the cab. Insert the syringe then push and twist to get a seal. Inject with water, withdraw the syringe and turn the regulator back to its original position.

Next, the loco must be lubricated. Use Heavy Steam Oil from a quality supplier such as Roundhouse. Take off the lubricator cap, fill to just above the steam pipe visible inside, then replace the cap. It should only be finger-tight.

Only then should you fill up with gas. Propane/Butane mix is recommended. Pure propane is a bit too volatile, pure butane tends to sulk in the tank when it is too cold. In the Scots climate, it is wise to keep the gas cylinder in an inside pocket. Use a long gas filler-adapter such as the Roundhouse adapter Part GFA. The gas-filling valve is on the cab floor, on the same side as the lubricator. Make sure that the gas-control valve, other side, is closed. Before you attach the adapter and press, raise the locomotive at the rear. When the liquid gas reaches the base of the valve, ie the tank is full, it will vent and you will smell gas. Propane/butane is not poisonous, so you are quite safe.

The first time you light up, and indeed all the first run will be tentative.  Get to know the regulator – no gas, no fire – and how long to hold your lighter in front of  the flue. Get to know the noises as the flame lights and as it settles down. At around 20psi, ALICE may eject hot condensates from her short little chimney. Get to know the warning sounds. Run the locomotive on blocks until you have a ‘feel’ for the delicate balance of fuel flow, water flow and air.   

ALICE runs at 20 to 30 p.s.i. The safety valve lifts at 65, so in normal running, you should never approach ‘danger’ pressure. In addition, never forget regular lubrication. White arrows show where Three-in-one or similar should be applied  from time to time. The valve rods and piston rods should get steam oil (see above)

 


During their lifetime, the Quarries were not very well-known though they were rich in innovation and folk-lore. They suffered a little because a few miles south was the Festiniog Railway, also serving slate quarries. The management were masters of Public Relations, even before the term was invented. When the French wanted to find out about serious Narrow Gauge, it was to the Festiniog that they went. When Prosper Péchot wrote his Memorandum about volume transport on 2’/60cm gauge, it was the Festiniog that he cited as an example, not the Dinorwic. For the full story, you can refer to Tracks To The Trenches.

 

JIC Boyd The Narrow Gauge Railways of North Caernavonshire Volume 3 Oakwood Press 1986  

Colonel Péchot: Tracks To The Trenches Birse Press 2014