BR 9F Original Minitrix 9F. Modified Minitrix 9F

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1 BR 9F Original Minitrix 9F Picture courtesy and copyright Rob Rumori Modified Minitrix 9F Picture courtesy and copyright Noel Leaver The Prototype. Class: BR 9F Introduced: 1954 Total: 251 Length: 66 2 Weight: 139 tons 4 cwt (depending on tender type) The last of the dozen BR standards was the most successful and certainly the largest. It was also the shortest lived by steam s yardstick of decades rather than years. Original proposals called for a with many of the features such as the boiler and cylinders being in common with the Britannia's. Driving wheel diameter was to be 5 3 to improve on the running speed of existing s. This proposed Class 8 Mikado would have been a useful mixed traffic engine but from a freight train performance view the increase in adhesion over the existing s was minimal in relation to the potential increase in power. A Heavy Freight engine was not a priority for the Committee due to the large numbers of Stanier 8F s and WD Austerities which had been built during the war and returned to Britain. When design work commenced in 1951 the design was dropped by Riddles in favour of the design which was so successful with the War Department. The leaning towards standardisation failed due to the only parts being in common with the previous Standard engines the tender and cab fittings. Everything else from the boiler to the wheels was different.

2 There were several different tenders used with the 9Fs. The first 10 and the last 48 BR1G tenders with inset sides, as on the Minitrix model (see below). The remaining locos had flush-sided tenders with curved tops, mostly of the BR1C and BR1F types which were again similar externally. 20 had the smaller BR1B tender, and 6 had BR1K tenders with mechanical stokers. Often tender allocations changed during the life of the locos. The 9F was designed as a heavy freight locomotive and performed extremely well on a wide range of duties from slow coal trains on steeply graded routes to fast freights and petrol tank trains. Rather more surprisingly, it performed well beyond expectations on occasional passenger trains, mainly summer specials (it did not have steam heating so could not be used in winter). Reports of 9Fs reaching speeds of up to 90 mph caused BR to clamp down on this practice (90 mph with 5 ft drivers is equivalent to 120 mph with an A4 - apart from danger, these high speeds caused accelerated wear). They were used on the named trains such as the "Red Dragon" and "Master Cutler" on many occasions, and frequently on the "Pines Express" over the heavily graded S&DJR. As the 9F had no steam heating facilities these allocations were only during the summer months when extra traffic tested the capabilities of sheds to provide enough locomotives. Many of the turns required double heading, something the 9F s were able to eliminate with their power. As the western region rerouted the Pines Express and all other through traffic from the end of summer '62 the 9F's were wasted for the remaining years on local Bournemouth, Bath, Bristol services. On such lightly loaded trains, typically 3 coaches and maybe a van, their acceleration from station stops was rather brisk, to the extent that a gaurd was left behind at Blandford and had to follow by taxi, the train having been halted at Bailey Gate. Ten locomotives, Nos , were chosen to be fitted with the latest in Crosti boiler technology. These had a preheater for the water before it went into the boiler. This was in response to the need for coal savings to be made at a time when coal was in a critical position in relation to supply and cost. In the event the reduction in coal consumption did not match the predictions and the ten engines were put aside in 1958 for rebuilding. When they were rebuilt in the early 60s with standard boiler the bulbous steam pipes over the cylinders remained, preventing smoke deflectors being fitted and giving them a very distinctive and ugly appearance. Further experiments were carried out on 9F s with a mechanical stoker applied to Nos in an effort to increase the evaporation to lift the power output of the engines. This trial had a limited success but the decision was made to proceed with full dieselisation and the three engines were returned to normal. Interestingly the last 9F in revenue service was one of the these, No , running its last few turns as a with the side rods removed to the rear wheels, in June The Geisl oblong ejector was fitted to No (which was the highest number on the BR fleet list and the last steam engine to be built at Crewe) in 1959 with the objective to increase power for a given coal consumption, or to raise output from a poorer grade coal. Results were disappointing and no further engines were so treated although ran with the Geisl for the rest of its life.

3 The most famous 9F is Evening Star, the last steam locomotive to be built for British Railways, being out shopped from Swindon in March In recognition of this it was the only one of the 251 strong class to receive the BR Lined Green Passenger livery (the rest were plain, unlined black) and was also the only one named. The engines were built as follows: Numbers Builder Years Crewe Crewe Crewe Crewe Swindon Crewe Crewe Swindon Swindon Crewe 1958 The engines were allocated new as follows: Western Region Midland Region Eastern Region Midland Region Eastern Region Midland Region Eastern Region Midland Region Eastern Region Midland Region Eastern Region Midland Region Eastern Region Western Region They were repaired in the main workshops of the region of allocation and the designs parent office was, strangely, Brighton. Strange, considering no 9F s were allocated to the Southern Region. The Scottish region never had a permanent allocation of these engines although some did work there. First withdrawn: 92034, 92169, 92170, 92171, 92175, (1964) Last withdrawn: 92077, 92160, (1968) Preserved: 92203, 92212, The Model. The only model of a 9F in N Gauge is one by Minitrix which suffers in a lot of ways. Firstly it only has a passing resemblance to a 9F being the same body shell as used on the Minitrix Britannia s. The chassis is not accurate in terms on wheel diameter or spacing and, the most glaring error as far as the chassis is concerned is

4 the inclusion of flanges on the middle set of driving wheels, something which the prototype lacked to enable it to corner better. The valve gear is also woeful and not inclined as on the prototype. Because it is on a continental chassis the model is noticeably wide when compared to other British models, particularly kits of BR Standards. Minitrix produced two examples in unlined black with the late crest and Evening Star in lined BR Green with the late crest. The lining on is poor with only one orange stripe being shown rather than the true orange-blackorange as on the prototype. Both examples have a BR1G tender attached and both have a single chimney because of the use of the Britannia body. As was, to my knowledge, never attached to a 1G tender and had a double chimney all its life both models fall further as a result. Having painted such a dire picture there are some positives. Owing to the large number of wheels the average punter at a train show who knows a little about BR Standards will identify the model for what it is meant to represent. The chassis is a good one and the haulage power of the model is certainly up there with the prototype. With some adjustments notably a double chimney which most of the class attached to 1G tenders had these maybe made into a nice model, provided the owner doesn t mind the continental chassis. There is a kit available to convert the Minitrix 9F to a Crosti example. The kit allows the modeller to either have the Crosti or the reconverted Crosti (which was classified 8F by BR, down graded from 9F). The more important changes which can be made are: 1. Removal of 4.5 mm from the front of the boiler, just behind the smokebox, and the removal of 4mm from the front of the chassis. This gets the front bogie positioned much better. 2. Change the cylinder mounting so they slope upwards, and reprofile the cylinders. 3. Change the profile of the bottom of the smokebox on the left. (These changes were all described in an article in Railway Modeller June 1992.) 4. There is a detailing kit with replacement and rather better looking smoke deflectors and correct shape buffer beam available in etched brass from TPM. (See link below) 5. Add steam pipes to cylinders - these show through a cut-out in the bottom of the deflectors. 6. Replace water feed pipe to boiler with one of correct shape and position.

5 9F Single Chimney/BRIG Tender Photo Album Locomotive Date of Pic Place of Pic Reference Jan 54 Crewe Works BRILL V1N6 p Jan 54 Crewe Works BRILL V1N6 p Jan 54 Crewe Works BRILL V1N6 p Jan 54 Crewe Works BRILL V1N6 p Jul 67 Dillicar Troughs SW NOV82 p Oxford Shed LDSO p Feb 67 Oxenholme SFN p Jul 67 Grayrigg Bank SW NOV82 p Sep 55 Hendon SD NOV96 p Mar 55 Cricklewood Yard LI75 p Long Meg Widnes Anhydrite SW JUN91 p Dec 64 Ex ANNESLEY DEPOT SW JUL97 p50 Some useful links for the 9F: The author of this article can be contacted via