PROGRESSING

THE LNER B1 DESIGN

By Doug Hewson

I got fed up with seeing so called B1s some of which were quite immaculate especially at exhibitions, but all wrong and worst still calling them B1s.  When people tell me they are starting to build a Springbok and I am sorry but I just can't help replying with a groan. When they say "What", I then tell them that the only resemblance Springbok has to a B1 is that it does have the correct number of wheels but there the similarity ends and the K3 tender which Martin Evans has paired it with makes it look worse, even if it had been the correct width.

I always work to works drawings or my own measurements taken from the real thing.  I, too, am from a solid B1 area (Scunthorpe) I worked in the Structural Drawing Office at the steel works by the line side to Cleethorpes and Immingham. In summer time I used to take my sandwiches down by the line side and sit on a pile of steel beams to watch the B1s come by with the lunch time Up and Down trains. I thought the B1s were very handsome engines but there is no way that a Springbok, which irritates the hell out of me lives up to that accolade. 

As you know I have already designed the BR 2-6-4 Tank, the 4-6-0 Class 4, the Britannia, and well on with the BR Class 4 2-6-0 and I have redesigned the GWR 5700/8750 Class Pannier Tanks to works drawings.  The next target had to be the B1.

Progress to date is that all three drawings for the tender are complete.  This is the 4,200 gallon group standard tender which was fitted to all but the first ten B1s. The drawings show all five different types of tender (excluding the self-weighing variety, of which ten were built). All 410 lived with their own tenders throughout their lives.

There are notes on the drawings to say which tender belonged which engine. There are ones which had snap head rivets to fix the top plates to the sides, flush riveted ones similar. Ones with the coal plate position over the water dome, a drawing showing and the position of the coal plate later in life (The 1950s).

At the front end of the tender there are drawings to show the differences between the Darlington built ones and the Doncaster built ones. The Darlington built ones had inclined shafts to the water valves and the Doncaster ones and the North British ones were vertical.

There are two sets of frames for the B1s and they changed at 61340 This is all on the drawings. This included the tender frames. On locos 61400 – 61409 the drag beams were cropped off.

The tenders on locos 61001 to 61039 did not have intermediate buffers. The coal plates on all of the tenders were altered to suit the cab profile during the 1950s.

Tenders for the locos 61352 to 61354 and 61357 had snap head rivets to join the upper side plates to the upper side plates and 61355 and 6 + 61400 to 09 had these plates joined with countersunk rivets so apart from the step, they were flush sided. The remainder were all completely flush sided.

Non of the B1s had the K3 tender as Martin Evans has drawn to go with his Springbok.  All of them had the 4,200 gallon LNER Group Standard tender.  All of the tenders had steam brakes and a through vacuum pipe.

For the loco I have been concentrating on drawing all the differences such as six different driving and coupled wheels, four or five different smokebox fronts and five different front bogies. I haven't done anything about a self-weighing tender, yet!  I did not have any proper details for the valve gear but the late  Don Ashton sent me the whole of the full size details and they show dimensions of the valve gear in 64ths even on the full size!

The Steam Workshop already has the proper castings in stock for the buffers, tender horns, and all the suspension details, including the spring hangers and brackets, spring helpers, Spencer blocks, axlebox covers, and all the usual finishing details such as steam heating and vacuum pipes, etc. 

I have set out the details of the of all six driving and coupled wheels some of which had additional plates riveted to the balance weights.  The first ten B1s were built with V2 wheels.  The driving wheels had the balance weights 15-05° in advance of the crank.   The coupled wheels had the balance weights 3° in advance.  The details of all of these locos which had which plates are given on my drawings.  Note the difference between the two preserved B1s 61306 (Which is wrongly named Mayflower) and 61264.  Mayflower was an Immingham loco which I used to see regularly. 

I have drawn out the front views of all five of the different bogies and noted on the drawing which locos had which bogies so when building a loco to my drawings I would certainly pick a number and build that engine so you will not be disappointed, as there are many differences.  I have only drawn out one of the front bogies but there were two, one had leaf springs and one had coil springs bit it seems that 61264 had both!

I have also completed all the valve gear layout and the details. 

I have drawn the engine with the correct LNER 100A boiler with its sloping back head.  I have also drawn most of the various fittings, including the manifold, fire hole doors, regulator handle, reverser, all the valve gear, including the layout, cylinders and drain cock gear brake gear including an arrangement drawing.  At present I am just working on a suitable design for the “SJ” vacuum brake ejector so that it looks correct, although internally it may not be so!

Smokeboxes are all drawn on Drg No8 and I have shown the smokebox drawn as a flat plate . There are quite a variety of front views to the B1s.  The first 10 B1s had smoke box doors which were 4 25/32 outside diameter and were 11 11/16 radius so were very flat. This applied to 8301 to 8310. They also had the door hinges at 2 1/8 centres and the hand rails were bent inwards and then exactly followed the radius of the door.

Following this they had doors which were 5 1/16 in diameter and ad a much more pronounced curve at 10 27/32 radius. The hinges on these smokeboxes were very narrowly spaced at 1 5/16 centres. The number plates then had to be placed above the top hinge. The handrails from now on were radiused from the outside handrails to the knob in the top centre. Locos from 61190 were fitted with a step on the door but these were dispensed with later.

From locos 61350 onwards the smokeboxes changed again and although the diameter remained the same at 5 1/16, this time the radius of the door changed to 6 7/8 giving them a much more pronounced domed effect.  The door hinges reverted to the 2 1/8 centres so the number plates in this case were placed below the top hinge.

I have drawn up the cylinders on Drg 7 and all that goes with them, but I have included a rear cover which the B1s did not have.  They were blind bored similar to the A1s, A2s, A3s, A4s and the V2s.  I thought that it would make sense to do it this way so that  the bores could go straight through. 

I have shown the superheaters on this drawing and they are a departure from the usual single row as I never think that we have enough superheat on our 5” gauge locos.  I first tried this on my BR 2-6-4 Tank loco, the 4MT with great success which is very economical.  The superheater elements are only 5/32 in diameter and with a double, double bend in them they will fit down a ¾ x 18swg tube, and still one can get a flue brush down the tubes so they can be kept clean. There are no obstructions in the smoke box to interfere with the cleaning operation as the main steam pipes go straight down the insides of the smokebox and into the stem chests.  The header for the for the superheaters is tucked right in the top of the smoke box the same as on the full size engine.  The upper set of elements is radiant, and the lower set ends at the fire box tube plate and there are ferrules on some of the side stays in case you want to fit a brick arch inside the fire box. There are 58ft of elements in my smoke box.

There is the conventional LNER anti vacuum valve on top of the smoke box.

 

The drawing No11 is all of the side platforms and would you believe they consist of 23 pieces!  I have, of course detailed them all off the joints in the engine as I could now obtain a works drawing for these.  Also detailed on there are the cab with a view inside the left hand side of the cab and the roof will be on Drg 9.  Also detailed on there is the front cab window frames and the cab side windows, the vacuum brake reservoir, steps including the left hand one which has been modified to accommodate the AWS box behind the cab step and the grab rail to fit on the front platform. 

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