A Defence of the Midland/LMS Class 4 0-6-0

midland-class-4-coverA Defence of the Midland/LMS Class 4 0-6-0 – also why frames cracked and axleboxes ran hot.
Author Adrian Tester.  Published by Crimson Lake.
ISBN 978 0 957 0779 0 4

Following the lead of authors such as E S Cox and A J Powell, locomotive enthusiasts have vilified the Midland/LMS 4F 0-6-0 as being next to useless. Yet this criticism overlooks the fact the class represented 10 per cent of the LMS locomotive stock, furthermore, it is at odds with the higher opinions of the machine held many of those who drove, fired or maintained 4Fs, men with rather closer experience.

Recent research reveals enthusiasts have been misled.

Individual chapters are devoted to explore in-depth the three main criticisms the above writers made – frame cracking, overheated bearings and poor steaming.

While the class suffered from frame cracks it returned a far better performance than many later classes e.g. LMS Class 5 4-6-0, LMS Class 8 2-8-0 and BR Class 7 4-6-2, while differences in frame performance cause by different works’ practices reveal the problem had causes other than design.

Its ‘under-sized’ bearings are demonstrated to have been no smaller than those fitted to other powerful inside-cylinder engines. Lubrication and bearing performance is comprehensively investigated to reveal the substitution of cheaper oil and bearing metal by the LMS was the cause of much of the problem. Even if you have no particular affection for the class, the chapter on axlebox performance alone could justify purchase!

Short-lap valves were no handicap to an engine primarily intended for low speed work while as An Introduction to Large-Lap Valves & Their Use on the LMS demonstrates, in North America engines with laps only a little longer hauled some of the world’s fastest high-speed trains.

The criticism of its poor steaming is addressed; the solution was simple. The whole class could have been treated for less than the cost one of its supposed replacements. Indeed in terms of value for money, which is also explored, those with no particular affection for the class may be amazed!

This is an in-depth but easy to read appraisal aimed at the serious student of locomotive engineering.

274 pages 63 tables   120 diagrams and photographs .

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Note: Proceeds from the sale of this book will accrue to Advanced Steam Traction Services Ltd (ASTS), and will be used to fund its work improving the performance, reliability and/or economy of steam locomotives.