Imaginary Locomotives

[Compound2632]

Don't use turntables, use wyes instead.  Plenty of room in our parallel universe.

 

Plenty of room needed, given the rigid wheelbase of some of these!

[Corbs]

Plenty of room needed, given the rigid wheelbase of some of these!

I tried as hard as I could to keep most of them not too much more than a 9F

Edited January 20, 2018 by Corbs

[BernardTPM]

I tried as hard as I could to keep most of them not too much more than a 9F

Ah, but a Britannia is longer than a 9F (and a Princess Coronation even longer). Don't be fooled by the number of coupled wheels!

[Corbs]

Ah, but a Britannia is longer than a 9F (and a Princess Coronation even longer). Don't be fooled by the number of coupled wheels!

Overall length or rigid wheelbase (or driving wheelbase)?

[PhilJ W]

I mentioned the Holden 4-6-0's (B12) a few pages back. A mixed traffic version with smaller wheels would be useful, perhaps even as a 2-6-2?

[BernardTPM]

Overall length or rigid wheelbase (or driving wheelbase)?

Overall, but I'm guessing I was at cross-purposes there. Sorry!

[Compound2632]

Sorry to start a hare. It was coupled (and hence-ish) rigid wheelbase I had in mind but I accept the point that that of these eight-coupled behemoths is no more than that of ten-coupled goods engines such as the 9F and Austerity.

[Corbs]

I mentioned the Holden 4-6-0's (B12) a few pages back. A mixed traffic version with smaller wheels would be useful, perhaps even as a 2-6-2?

Hmm an interesting one, would it still be inside cylinder? I wonder if there would be enough room for cylinders and motion with a 2-6-2.

[Lu4472ke]

Hmm an interesting one, would it still be inside cylinder? I wonder if there would be enough room for cylinders and motion with a 2-6-2.

 

You could always do both inside and outside versions.

[jcm@gwr]

Hmm an interesting one, would it still be inside cylinder? I wonder if there would be enough room for cylinders and motion with a 2-6-2.

 

 

You could always do both inside and outside versions.

 

Outside cylinders and inside motion?

[Corbs]

Well, I started thinking about a goods design based on the B12.

 

I ended up with this, guess by this stage it would be the LNER T2.

It uses the same boiler, cylinders, front bogie and fittings as the B12, same loco length. Stretched the tender though.

 

Edited January 21, 2018 by Corbs

[Corbs]

The W2, built on the same basic components?

(Now altered to give it a taller cylinder placement like the J20 so the motion can clear the first axle)

Edited January 21, 2018 by Corbs

[DCB]

The 4-8-0 would really need to be based on the J38 rather than the B12 as the connecting rods would be crazily short with leading axle drive.   Inclined cylinders and drive onto the second axle would be needed to get a reasonable length of con rod and let the rod and the valve gear clear the leading axle and bogie. The GW could not build a 4 cylinder 4-8-0 version of the 4700 for the same reason, no clearance with small driving wheels.

The B12 was really an over elongated 4-4-0 in any case and keeping the same cylinders and valve gear for a 4-8-0  or 4-6-4 T would result in an excessively long loco.

[Niels]

Today is your lucky day also.

 

'Ah, Mr Riddles, I've been looking for you. I say, your office does seem to be rather smokier than usual, and what's that scent?'

 

BR-STD-9F-tank-1.jpg

 

 

 

A first step in the rational 1984 range of standard locomotives.

All shall have 5 feet driving wheels and wide fireboxes.

Hail Big Brother.

 

https://imgur.com/GqDOFMW

[Dr Gerbil-Fritters]

Regarding wheelbases, am I correct in thinking the 9F had blind centre drivers and increasing degrees of sideplay on the axles on either side of the centre axle?

 

For illustrative purposes, here is how a Main Depot would be laid out in our imaginary world. 

 

 

Smaller running depots would have the same arrangement but without the maintenance buildings.

 

 

These are obviously real examples, being steam servicing facilities built in the late 1990s but they still clearly show the principles laid out by the Norfolk and Western and partially adopted by the LMS (and latterly BR) in being designed around the 'garage' system with a logical and simple flow of engines around the facilities.

Edited January 21, 2018 by Dr Gerbil-Fritters

[Corbs]

The 4-8-0 would really need to be based on the J38 rather than the B12 as the connecting rods would be crazily short with leading axle drive.   Inclined cylinders and drive onto the second axle would be needed to get a reasonable length of con rod and let the rod and the valve gear clear the leading axle and bogie. The GW could not build a 4 cylinder 4-8-0 version of the 4700 for the same reason, no clearance with small driving wheels.

The B12 was really an over elongated 4-4-0 in any case and keeping the same cylinders and valve gear for a 4-8-0  or 4-6-4 T would result in an excessively long loco.

 

You're right, it would need to drive to the second axle, maybe like the J20 which used the B12 boiler, cylinders and motion. In this case the connecting rods would need to be longer to get to the 2nd axle? I'll adjust them to give it a bigger/higher cylinder cover like the J20.

https://www.lner.info/locos/J/j20.php

 

The 4-8-0 is based on a King rather than a 4700, with the 4 cylinder front end layout (see comparison below) - this is what I meant by it being a Collepelon rather than a Chapelward

The centre point of the first axle is in the same place as the King, so it could drive on the 1st and 3rd axles instead of 1st and 2nd?

 

 

The GWR 4 cylinder locos have the inside cylinders placed well forward and drive on to the front axle - see animation below.

Edited January 21, 2018 by Corbs

[Compound2632]

Well, I started thinking about a goods design based on the B12.

Stretched the tender though.

 

But the point of the short tender on the Holden 4-6-0 was to squeeze it onto the Great Eastern's small turntables.

[Coryton]

Think about that for a moment... I believe that this was done with the auxiliary water tanks used by some South African lines, dropping the tank and running round it, because the LOCO runs bidirectionally, but it wasn’t preferred to push the tender. However for a coal/water tender (1) it needs to be BEHIND the loco (2) it ALSO needs to be the right way round...

 

I thought the suggestion was that second tender would be just for water, so you uncouple the water tender, run onto the turntable with the coal/water tender, leaving it next to the locomotive and the right way round, then run round the water tender and couple it back on - the other way round - but it doesn't matter for that one.

 

I presume that tenders and locomotives could be turned separately, but that sounds like a bit of a faff.

[Corbs]

But the point of the short tender on the Holden 4-6-0 was to squeeze it onto the Great Eastern's small turntables.

D'oh! Well at least in this case the smaller tender could be used. 

At the moment I'm working with the wye concept to get rid of turntables as a limiting factor.

[rockershovel]

I thought the suggestion was that second tender would be just for water, so you uncouple the water tender, run onto the turntable with the coal/water tender, leaving it next to the locomotive and the right way round, then run round the water tender and couple it back on - the other way round - but it doesn't matter for that one.

 

I presume that tenders and locomotives could be turned separately, but that sounds like a bit of a faff.

We’re not quite on the same page, here; but since the question has been raised;

 

The auxiliary water tenders used in places like SA, are/were just tank cars. The extra tenders used on locos like the Flying Scotsman, were converted from conventional tenders, and also include features like the corridor.

 

Photo here, seems to show conventional buffing and drawgear

 

 

So I would guess that if the necessary hoses and couplings were fitted, it could indeed be detached and re-attached, and run bi-directionally. However I suspect that it would be no great matter to turn in separately on the turntable, and re-attach conventionally? Perhaps someone who is familiar with the type, might shed some light on the matter?

Edited January 21, 2018 by rockershovel

[Corbs]

Oh, I thought we were in agreement. The stanier tender in the photoshop is non-corridor, and only carries water, so my point was that it could have a water hose at each end so it could be connected/disconnected/reconnected to the conventional tender. Just fit it with conventional buffers and drawgear at each end, like when they are converted into water carts.

[rockershovel]

Oh, I thought we were in agreement. The stanier tender in the photoshop is non-corridor, and only carries water, so my point was that it could have a water hose at each end so it could be connected/disconnected/reconnected to the conventional tender. Just fit it with conventional buffers and drawgear at each end, like when they are converted into water carts.

I think we’ve crossed posts.

 

My best guess would be that since AFAIK, no British locomotive ever used an auxiliary tender in revenue service, the actual outcome would be to include the necessary watering in the programme.

Edited January 21, 2018 by rockershovel

[Coryton]

The auxiliary water tenders used in places like SA, are/were just tank cars. The extra tenders used on locos like the Flying Scotsman, were converted from conventional tenders, and also include features like the corridor.

 

Photo here, seems to show conventional buffing and drawgear

 

345A5D83-91C6-4A60-A329-687E12798BC3.jpeg

 

 

I thought that (in the UK at any rate) a tender with a corridor connection and buckeye coupling was anything but conventional.

[rockershovel]

I thought that (in the UK at any rate) a tender with a corridor connection and buckeye coupling was anything but conventional.

See above. I can’t find any reference to any British locomotive using an auxiliary tender in scheduled revenue service. I can’t find any reference to any locomotive, other than a Gresley Pacific, using a corridor tender.

 

Any tender with conventional buffing gear and/or couplers both ends, would be a conversion. The one in the photo was attributed to having been built for Flying Scotsman, but subsequently used with an A4 (hence the blue paint)

Edited January 21, 2018 by rockershovel

[Corbs]

Yes the issue we are trying to solve is these monster locos' coal consumption, so sacrificing some water space in the main tender and having a water cart. If you have a wye, this isn't an issue, but if you are restricted to turntables, to avoid having to build very very long ones, the water cart could work.

 

The only water tender in the UK as you say was built to go with 4472 (subsequently Bittern) after the demise of water troughs and water columns. I didn't know they had kept the corridor though!

Having the same connections at each end makes sense as:

a) the loco can still operate without the water tender (albeit with reduced water capacity)

b) the turntable doesn't need to be very very long

c) the tender can be uncoupled and recoupled to different locos depending on need/direction