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WSR Bogies...

 • The BR MK1 Coach and its bogies...a brief insight
In common with most other standard gauge preserved or heritage steam and diesel railways in the United Kingdom, the West Somerset Railway has acquired a number of ex BR MK1 vehicles over the years. Many of the coaches have stayed on the WSR, and others have been disposed of or sold on to other railways. The MK1 coach was British Railway’s first standard corridor coach (both for passenger and other use) and was in production from 1950 to 1964, after this the ‘new’ prototype MK2 coach was already being designed. Their standard dimensions for passenger carrying stock are 63 ft. 5 ins. long by 9 ft. 3 ins. wide. They have all welded steel construction of the bodies, Pullman gangways and buckeye couplings. (Please see separate feature on couplings, their design and their meanings)
Jon Tooke explains the mysteries of the Bogie. Jon is a regular Guard on the Railway and also took the pictures below. Jon Tooke
 • The B1 Bogie
From the earliest production models, the coaches and other vehicles rode on BR MK1 bogies. (B1)
The leaf springs would absorb any movement or resonance and have a damping effect to the overall ride quality. The wheels, which are cast as a one-piece item in a pair with their axle, ride with the outermost edges of the axle in a roller bearing contained in an oil filled axle box. The oil in these boxes had to be topped up at regular maintenance times to avoid the bearing running hot and from seizing up altogether.
A man known as a wheeltapper was employed at large railway stations to check that the wheels on the bogies were sound and that the axle boxes were not hot. By using a long handled wheeltapping hammer he would strike the wheels of the bogie and hear if it ‘rang true’ (a wheel with a crack in it would give off a dull sound), and with the back of his hand he would determine whether the axle box bearing was running hot.
Today, lineside electronic devices, and ultrasonic equipment in maintenance sheds are used to perform this same duty.
B1 bogie
 • The Commonwealth Bogie
From the late 1950’s saw a progression on from the BR MK1 bogie when the Commonwealth bogie was designed and introduced to all BR MK1 vehicles.
The design had changed somewhat from the BR MK1, and now the bogie was formed of a heavy cast steel design with fitted sealed roller bearings on the axle ends. This done away with the need to have the oil in the axle boxes checked and replenished at regular intervals. Either SKF or Timken manufactured the bearings. The leaf springs had been replaced with coil type springs which ran vertically rather than horizontally, but still had the effect of damping down all the vibrations and resonance associated with higher speeds of rail travel. Due to the design of the bogie and advancement in engineering, the commonwealth bogie gave a far superior ride quality over the MK1 type of bogie. The commonwealth bogie was rated for running at 100 miles per hour as opposed to the BR MK1 bogie which was only rated at 90MPH, and due to it’s design, each bogie weighed in at a hefty 6.75 tons!
A great number of the WSR coaching stock now runs on commonwealth bogies. These are being fitted when a coach goes to the Carriage and Wagon works at Minehead for overhaul. Commonwealth bogies can still be seen on vehicles on the mainline, for example, the coaches in the charter train sets run on them as do the ReS vans and TPO vehicles.
Commonwealth bogie
 • The B4 Bogie
From 1963, BR introduced a new type of bogie for their coaching stock. This was classed as the BR MK4 (B4) type of bogie.
The B4 bogie was of a fabricated steel design with fitted Roller bearings similar to those on the commonwealth bogie. Again, the springs were of the coil type, but now two were fitted above each axle as opposed to 2 as seen on the commonwealth bogie. During BR days, only a very small amount of MK1 stock was fitted with the B4 bogie from new, but this bogie was used to replaces the older worn out examples of the B1 bogie. When launched, the BR MK2 coach carried the B4 bogies from new.
From an aesthetic point of view, the B4 was not as elegant as the commonwealth, but it gave an equal ride quality and was far superior to that of the B1 examples. BR too passed this bogie for 100MPH running, and due to its construction, it was lighter than the commonwealth, with each bogie weighing in at 5.2 tons.
Today, you can find examples of the B4 bogie underneath WSR coaching stock, as well as examples on vehicles on the mainline railway network.
B4 bogie
 • In conclusion...
Jon concludes with "So, the next time you have a ride on a train on the WSR, you can be assured that smoothness of your journey is due to either the Commonwealth or the B4 bogie that the coach is sitting on.Why not try and spot which coaches are running on which type of bogie? "
This page is not from the official West Somerset Railway website   
© Stephen Edge