NG6 TENDER LOCO - part one

by Trefor Milns

Photograph by Christopher Glover (click photos to enlarge)

I foolishly chided the Editor a little while back for showing a southern bias in not reporting more northern events.  You will not be surprised to learn that the consequence of poking your head above the parapet was an invitation (?) to do something about it, and write an article about my recent acquisition of a gold medal winning 5” gauge South African Railways Class NG6 locomotive.  It is based on a prototype 2 foot narrow gauge locomotive which had been mounted on a plinth at the premises of the Rand Society of Model Engineers, Johannesburg – the 2½” to the foot scaled model was designed, built and completed in 1973 by Angus Walker, then Chairman and (later) President of RSME .  Angus is now 91 and still building locomotives.  The story of the original railway is just as interesting as the construction of the model, so I shall give a little history first.
Potted History
The railway was proposed by Cecil Rhodes to provide a more rapid transport link for freight and passengers between the East coast of Africa and what was to become Rhodesia.  The land route took about 3 months by oxen cart trains and many lives were lost – both cattle and human – on the arduous trek.  Following lengthy negotiations, the line was constructed from Beira on the Portuguese Mozambique coast to Umtali in Mashonaland (later Rhodesia) – a distance of 222 miles on 2 foot gauge lines, climbing some 3500 feet in 150 miles – with 2500 of these being tackled  in just 70 miles, the ruling gradient on the final stretch being 1 in 50.  The line was completed in 1896, and cut the 3-month trek to 2 days, although delays often occurred due to derailments on the lightweight and rudimentary trackwork, using only 20lbs per yard rail.
All the locomotives for the railway were provided by Falcon Engineering, Loughborough – later to become The Brush Electrical Engineering Co Ltd, and the Falcon Works are still extant under the Brush name.
Fig 1. Beira Railway Nos. 1-3
The first three locomotives (Fig 1) were provided in 1893 to a 0-6-0 design – similar to the Falcon Class B, but with a short 4-wheeled tender rather than side tanks.  These were very “pretty” engines, but were dogged by constant derailments, as a result of the long fixed wheelbase, to the point that they were quickly modified to a 0-4-2 arrangement by removing the rear coupling rods.  This reportedly improved their ability to cope with the prevailing track work.
Fig 2. Beira Railway Nos. 4-9
The next batch of 6 locomotives (Fig 2) was modified to a 4-4-0 design (Falcon Class F2) supplied in 1895 with minimal changes to the original class, and the similarities are evident in the works photograph.
Fig 3. Beira Railway Nos. 10-45
These were a great improvement on the original design, but were a little underpowered so the remaining 36 locomotives supplied between 1896 & 1898 (Falcon Class F4 – Fig 3) were further modified with a slightly larger boiler, long smokeboxes, increased cylinder diameter (9” as opposed to the F2’s 8”dia), single-bar crossheads (as opposed to the F2 double-bars), conventional chimneys and a larger 6-wheeled tender.  These enhancements increased the maximum train weight from 160 tons to 180 tons.  Falcon built Nos. 10-35 at Loughborough, but the final batch (Nos. 36-45) were built under contract to Falcon by Glasgow Engineering to the same design (presumably Falcon/Brush by then were concentrating on electrical traction).  
By 1900, the traffic had increased to the point that narrow gauge could no longer cope, and the whole 222 miles was re-gauged to Cape Gauge (3’6”) in just 6 days.  All of the locomotives were moth-balled in one of the Depots at Bamboo Creek – some of them, of course, only being 2 years old !
Eventually some of the locomotives found their way to various industrial railways, with a lot of the track and stock going to the Ayreshire Railway.  In 1916, South African Railways bought 13 engines from Bamboo Creek and, by mixing and matching the best bits off each, created just 11 of a new Class – the NG6 was born.  These were numbered NG6 Nos.96-106.  The following photograph (Fig 4) shows how mixed-up the NG6’s could be – this one, No. 105 used an F2 chasis (Falcon No. 231, Beira No. 8), with a Glasgow Engineering F4 boiler and a substituted Fowler 8-wheeled double-bogied tender.  These were affectionately known as ‘Lawleys’ after Alfred Lawley, the Engineer for the original Beira Railway.
Fig 4. SAR NG6 No. 105
Go to Part Two for details of the model.SAR_Lawley_2.htmlSAR_Lawley_1_files/JoL%20CG%2001.pngSAR_Lawley_1_files/image2.jpgSAR_Lawley_1_files/image3.jpgSAR_Lawley_1_files/image4.jpgSAR_Lawley_1_files/08%20SAR%20NG6%20No.105%20%28F2%20234%29.jpgSAR_Lawley_1_files/JoL%20CG%2001_1.pngshapeimage_1_link_0