The engines represented by this kit were built by the Midland Railway in a number of batches between 1875 and 1900, for use on secondary passenger services. The LMS subsequently modified a number of them for use on motor train (push/pull) working when this type of train was introduced to try and reduce operating costs on little used services.
Apart from the batch of engines with the larger wheel size, there were three principal visual variations within the class. Firstly, between the mid 1920s and 1928, a substantial number of the engines had their round top firebox replaced with a Belpaire one, often with Ramsbottom safety valves, but eventually all had "pop" valves.
Secondly, the LMS fitted a number of the locomotives (both with round top and Belpaire fireboxes) with motor-train control apparatus. Thirdly, a number of engines carried condensing apparatus, mainly for use in the London area.
Due to the large number of variations, members of this class exhibited over their long life span, it is recommended that a good photograph of the engine to be modelled be obtained. There are a number of good reference books available, inter alia, An Illustrated History of Midland Locomotives, Volume ?, An Illustrated History of LMS Locomotives, Volume 4, Locomotive Liveries of the LMS, and British Locomotive Catalogue 1825-1923, Volume 3A.
The MSC Models Kit
The kit enables the 1P to be built in either the original round top or Belpaire firebox versions. Fittings for motor fitted and condensing variants are not supplied, but the modeller could add these by fabricating the parts themselves. The 5' 7" wheel variants had slightly larger wheel splashers, but these are not catered for. Again, if the modeller wanted to make the alterations themselves, this batch could be built from the kit.
The kits can be powered by a number of different motor units, but the MSC Models JH motor unit is particularly recommended.
Wheels have not been provided in the kit as there are a number of different standards available in O Gauge. Slaters Plastikard Ltd and Walsall Model Engineering wheels are recommended. The driving wheels are 5' 4" 14 spoke wheels, whilst the bogie wheels are 2' 9" 9 or 10 spoke wheels - photographic evidence indicates both were used.