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Building the L&NWR ‘Samson’ Class 2-4-0 Passenger Engine
The Prototype
Following on from the building of the Lady of the Lake class 2-2-2 express engines between 1859 and 1865, the CME of the L&NWR, John Ramsbottom, went on to design a new four coupled engine, known as the Samson class. These were first built in batches from 1863 through to 1879 and 90 were constructed altogether. With 6ft wheels plus 3” tyres and 16” x 20” cylinders, they were good all round locomotives that gave stout service until most of them were scrapped between 1889 and 1894, with just 10 being retained for ‘Engineers’ duties. This latter term meant that they were kept at specific locations for use with the Chief Engineer’s saloon when inspecting civil engineering works or other items of infrastructure.
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As will be understood from the wonderful photograph included here, I have a soft spot for these locomotives. To explain further, once Webb took over in the early 1870’s, he designed and introduced his two classes of 2-4-0 locomotives with Allan valve gear; one being known as the 6’ 6” Precedents which are suitably famous as a class and the lesser known 6’ Whitworths that had the same wheel arrangement. These groups of locomotives were collectively known as large and small Jumbos. The Whitworths were given the same wheels, names and numbers as used originally on the Samsons and although the latter locomotives were described as ‘rebuilds’ they were really new engines.
Now back in 1969, my first 5” gauge locomotive model was based on a design offered by LBSC as an enlarge-ment of his 3½” gauge ‘Mabel’. The proportions of the chassis layout did not offer a realistic appearance, so I found some 4mm scale drawings and also scaled my model from a picture I had of a Whitworth in a railway journal at that time. The locomotive had the name ‘Hotspur’ and was numbered 631. So those of you who have read my notes over the years will now appreciate where my pen name and trading arrangement came from. The Samson version of Hotspur actually became Engineer Manchester in 1906 and lasted until she was scrapped in 1914 to be replaced by the Whitworth called Sphinx.
Now back in 1969, my first 5” gauge locomotive model was based on a design offered by LBSC as an enlarge-ment of his 3½” gauge ‘Mabel’. The proportions of the chassis layout did not offer a realistic appearance, so I found some 4mm scale drawings and also scaled my model from a picture I had of a Whitworth in a railway journal at that time. The locomotive had the name ‘Hotspur’ and was numbered 631. So those of you who have read my notes over the years will now appreciate where my pen name and trading arrangement came from. The Samson version of Hotspur actually became Engineer Manchester in 1906 and lasted until she was scrapped in 1914 to be replaced by the Whitworth called Sphinx.
The Model
I am indebted to colleagues in the London and North Western Railway Society for their help in providing what information exists for this historic locomotive. It is a very basic design and therefore relatively simple to construct.
The prototypes had small cylinders; initially with a diameter of 15¼“ that were quickly enlarged to 16” and we can use 1¼” diameter bores with 1¾“ stroke as the cylinder size will be similar to my Coal Tank design with valves in between the bores and Stephenson’s valve gear in a horizontal line through the coupled axles. This will mean using a pair of slightly smaller cylinder blocks compared to the CT, but this is a good thing as too much weight over the leading wheels would be a disadvantage from an adhesion standpoint. In fact, I am seriously thinking about using fabricated cylinder blocks as these will be lighter. The steam chest will also have to be shorter but for the model, I will retain its external supplementary steam chest that I believe to be beneficial for the best steam admission. This feature is something I learned from the late Don Young as he had introduced it on his Isle of Wight 0-4-4, 5” gauge ‘Fishbourne’ design. Most valve chests have ample space around the slide valve but with such a small steam chest and quite large valves, the admission of steam is enhanced by providing an adjacent supplementary volume.
I can add that my good friend Simon Bowditch has set out the valve gear for me and this should mean we have every confidence on the engine’s performance. The reverser is another of the typical Ramsbottom designs and this time, due to the proximity of the trailing coupled wheels, the mechanism will have to be included with the cab side sheet platework rather than be mounted on chassis brackets as we try to do. In this picture the smoke box has vertical front with a horizontally hinged door but there are variations and I strongly advise any prospective builder to seek out a version of the locomotive that appeals. Some early locomotives had the customary sloping front and much later they all had round doors set vertically. Here the safety valves are the Ramsbottom type without the casing fitted later.
The leading and driving axles will be sprung on leaf springs and as usual I want to incorporate this detail as closely as possible. The trailing axle is actually very simple as it has a horizontal plate stay and underslung coil springs as most basic model locomotives have. This surprised me as Ramsbottom had incorporated what subsequently became the L&NWR standard transverse beam suspension on his Lady of the Lake but not here.
For stiffness however, we have the integrity of a substantial dragbox to form the traditional link to the tender.
The tender will be seen to be the earlier of the Ramsbottom designs i.e. lower in height and only 1500 gallons capacity. Those of you who have prior knowledge on these matters will see that the side sheets for the tender have three vertical rows of rivets forming the joints or caulking seams as at that time Crewe works could not handle sheets of wrought iron for the full length of the side. There are also round buffers on the front of the tender at the time this picture was taken, but I have seen the earlier version that existed pre-Ramsbottom that has square buffers. The axles ran in greased axleboxes and it appears to me that the footsteps are fabricated like those on the locomotive at that time.
For those that may wish to build a really early version of this locomotive then open splashers with slots would be appropriate and just a spectacle plate without the Webb style cab and roof. Both however, will have the taller chimney, at least initially, as later on an upgraded boiler would have been set higher from the railheads and so the loading gauge would have meant the more usual chimney height being used.
Lastly, there is an intriguing puzzle as to how the steam brakes would operate on both wheels with only one drawbar from the brake cylinder, but more on this when we get there. As usual, drawings, castings and the laser cut materials will be available from me. A price list will also be added here as soon as it is available.
The prototypes had small cylinders; initially with a diameter of 15¼“ that were quickly enlarged to 16” and we can use 1¼” diameter bores with 1¾“ stroke as the cylinder size will be similar to my Coal Tank design with valves in between the bores and Stephenson’s valve gear in a horizontal line through the coupled axles. This will mean using a pair of slightly smaller cylinder blocks compared to the CT, but this is a good thing as too much weight over the leading wheels would be a disadvantage from an adhesion standpoint. In fact, I am seriously thinking about using fabricated cylinder blocks as these will be lighter. The steam chest will also have to be shorter but for the model, I will retain its external supplementary steam chest that I believe to be beneficial for the best steam admission. This feature is something I learned from the late Don Young as he had introduced it on his Isle of Wight 0-4-4, 5” gauge ‘Fishbourne’ design. Most valve chests have ample space around the slide valve but with such a small steam chest and quite large valves, the admission of steam is enhanced by providing an adjacent supplementary volume.
I can add that my good friend Simon Bowditch has set out the valve gear for me and this should mean we have every confidence on the engine’s performance. The reverser is another of the typical Ramsbottom designs and this time, due to the proximity of the trailing coupled wheels, the mechanism will have to be included with the cab side sheet platework rather than be mounted on chassis brackets as we try to do. In this picture the smoke box has vertical front with a horizontally hinged door but there are variations and I strongly advise any prospective builder to seek out a version of the locomotive that appeals. Some early locomotives had the customary sloping front and much later they all had round doors set vertically. Here the safety valves are the Ramsbottom type without the casing fitted later.
The leading and driving axles will be sprung on leaf springs and as usual I want to incorporate this detail as closely as possible. The trailing axle is actually very simple as it has a horizontal plate stay and underslung coil springs as most basic model locomotives have. This surprised me as Ramsbottom had incorporated what subsequently became the L&NWR standard transverse beam suspension on his Lady of the Lake but not here.
For stiffness however, we have the integrity of a substantial dragbox to form the traditional link to the tender.
The tender will be seen to be the earlier of the Ramsbottom designs i.e. lower in height and only 1500 gallons capacity. Those of you who have prior knowledge on these matters will see that the side sheets for the tender have three vertical rows of rivets forming the joints or caulking seams as at that time Crewe works could not handle sheets of wrought iron for the full length of the side. There are also round buffers on the front of the tender at the time this picture was taken, but I have seen the earlier version that existed pre-Ramsbottom that has square buffers. The axles ran in greased axleboxes and it appears to me that the footsteps are fabricated like those on the locomotive at that time.
For those that may wish to build a really early version of this locomotive then open splashers with slots would be appropriate and just a spectacle plate without the Webb style cab and roof. Both however, will have the taller chimney, at least initially, as later on an upgraded boiler would have been set higher from the railheads and so the loading gauge would have meant the more usual chimney height being used.
Lastly, there is an intriguing puzzle as to how the steam brakes would operate on both wheels with only one drawbar from the brake cylinder, but more on this when we get there. As usual, drawings, castings and the laser cut materials will be available from me. A price list will also be added here as soon as it is available.
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+44 1600 713913
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address
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1 Highmeadow, Wyesham, Monmouth, Monmoutshire NP25 3TB
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Last updated 15th September 2019
