Niels

17 hours ago, JimC said:

I

 

I'm quite pleased with the look of this boiler, if I'm not kidding myself it gives the locomotive a more purposeful look than the Manor. In reality of course Collet's team would surely have considered and rejected a shortened Std 1 like this before they went ahead and designed a complete new boiler for the Manor.

How will it look with 5 feet drivers and 16 inch cylinders?

If a two-cylinder Saint with 80 inch drivers can do 100 so this is limited to 75 with 60 inch drivers.

Fast enough for Wales.

On 28/12/2023 at 13:38, Flying Fox 34F said:

In a simplistic way, just reduce all dimensions by 12%.  It should fit reasonably.

Ironically, the same figure is the difference between OO and HO!

 

Paul

If You can afford it ,it has already done.Photoshop Coppercap

Click Picture for enlargement.Once ,wait ,Once more.

On 27/12/2023 at 09:53, Flying Fox 34F said:

Just rescale the whole drawing to fit an appropriate British Loading Gauge.  There are plenty to choose from.  I’m sure someone can recalculate Tractive Effort of a smaller machine.

 

Paul

Let me try.

A Castle has two 406mm dia outside cylinders sitting 2184mm appart.

Mr Garbe in Germany designed a 2-6-0( P6) with full Krauss- Helmholtz front truck and two outside cylinders sitting 2080mm apart.

Prussian P6

That means a 2-6-4 with Castle wheels and cylinder dimensions could run the same routes as a normal Castle.

It could even have 508mm outside cylinders and  one inside with 762mm strokes and have more tractive effort than a King.And at lower pressure if wheels were 6 feet diameter

On 21/12/2023 at 15:58, JimC said:

I put this together after a thread on another forum. 
I've always considered that the chief issue with the Great Bear was excessively long fire tubes, but it was pointed out that there was at least one successful locomotive class with 23ft tubes - the German DRG05 4-6-4 that held the steam speed record with 200km/h on essentially level track. I took a look at the numbers, and basically if the Bear's firebox and grate were increased in size by about 25% the resulting proportions aren't so different from the DRG05. So here you are. 

It could also be a fourcylinder simple copy of Goelsdorf 310.Would solve the UK loading gauge problems  allowing a Krauss Helmholtz up front.

1 hour ago, rockershovel said:

Inside cylinders with outside valve gear never really rang any bells. It remained on the margins of European design, flattering to deceive for many years - the LNWR once experimented with it - but to no real effect. 

 

Exotic boiler designs were another European chimera which never really justified themselves. 

 

Chapelon was a real genius, a true innovator and his keynote designs look rather magnificent. 

Inside cylinders with  mostly outside valve gear pulled worlds fastest commercial  steam train in Belgium.

https://www.altaplana.be/en/dictionary/12.004

GWR surpassed everybody in crazyness,building fourcylinder locomotives with two inside valve-gears in 1950.

GWR also sired a lot of exotic/expensive  boilers  with corners and tapers everywhere and never proven superior to anything.

But Your evaluation of Chapelon will be true in all eternity.

Lovely

1 hour ago, rockershovel said:

Well, yes... but the whole thing, rods flapping around, no running board,...

The italians tried to improve performance.

A4,MN ,BoB&WC used tinplate to hide lousy engineering (valve drive).

10 hours ago, rockershovel said:

That Italian loco... I don't know what it is about Italian steam locomotives, but the national genius for style and design seems to have entirely left the arena. 

 

 

The picture was meant to show that Caprotti on Q1 was possible and would have been more user friendly.

Franco Crosti was ugly everywhere.

5 minutes ago, 62613 said:

Awful lot of stuff going round and round!

Two extra balance rods.

Benefit is very much less uncomfort and destruction of crew,locomotive,train and permanent way.

A K1 can then do anything better than a B1 and is 10 tons lower mass and cost.

1 hour ago, Jeremy Cumberland said:

Do you have an example of an inside-cylindered locomotive?

There are  pictures in a Q1 book  ISBN 0954485912 page 16 and 17?

Caprotti then?

Italian inside Caprotti

or

Stephenson

Outside Stephenson

or

Walschaerts

Waelschaerts outside to inside

1 hour ago, Jeremy Cumberland said:

Without pretending to understand much about it (beyond its being a poppet type of valve gear), the photograph seems to show it being driven only by a return crank, not by the crosshead, so I don't see why it shouldn't work on an inside cylinder locomotive. The valves would be difficult to get at though, being above the cylinders and between the frames, which might make it a less attractive proposition for inside-cylinder locomotives.

It is not a poppet valve gear but four low-mass piston valves per cylinder.

Try to find  the drawing in first link.

Cossart balance rod

34 minutes ago, AlfaZagato said:

Would that valve gear have worked on an inside-cylinder loco?

Even better I think.

On the outside cylindered 141TC they had to put a low mass (lots of holes) reverse rod to one end of the vertical crank that guides the heavy balancing rod.

On inside cylindered engines the normal practice is to have inside-crank throw and outside coupling pin opposite..

I cannot claim to understand the Cossart valve gear and will love to see a describtion (in french if need be).

The gear was not changed or altered from 1933 to 1970 and the 141TCs stopped and started an awfull lot of times

Bulleids Q1s have always fascinated me and I think they could have been improved and been best british 0-6-0 if they were not already.

Bulleid  went to France around 1936 to meet Chapelon and the Nord Pacific became ill somewhere north of Paris.

Locomoive exchanged and the very fast schedule kept.

He went forward to see the wonder engine and was impressed and very surprised

It was a surburban tank Nord 141TC that had Cossart valve gear that also acted as reciprocating balance for the steam pistons.

If the Q1 had had this valve gear it would  have been balanced 100% fore and aft and yawing or nosing.

Worlds safest and fastest inside cylindered 0-6-0.

And a little easier to maintain as all valvery can be reached from outside.

No eccentrics on crank and thus more robust.

Nord 141 TC page 211

141 model

19 hours ago, TerryD1471 said:

The climate within the LMS in the early 20s (under Hughes) suggested a freight 2-8-2 and a Pacific. We know that the MR powers trod on that idea and eventually a good 4-6-0 came out, but when eventually a pacific materialised (6200), there seemed to me to be an opportunity to have an equivalent 2-8-2 using a Princess boiler. This machine could have had 5'9" drivers and would have been ideal for the night sleepers on the WCML (not too fast) and also moving heavy stuff over the S & C. The clue was that the LNER had contemporaneously built a 2-8-2 (2001) and this might have suggested a similar solution, but it was not to be.

 

Nevertheless, I might just build a model of this imaginary machine; it might take place alongside my Stanier 4-6-4?

 A three cylinder compound based on 9f parts would have been a fitting finale

1 hour ago, rodent279 said:

Here's an imaginary loco that may have been touched on before.

The Hunsley Austerity 0-6-0ST had a short 11' wheelbase for 30'4" of loco. Would they have been better locos for short trip work if they had a leading & trailing axle, turning it into that rare beast the inside cylinder 2-6-2ST?

A simple modification for all inside 0-6-0 locomotives  can be to put balancing rods on the driver outside pins.

We balance ca 50% up and down as usual with counterweigths in the wheels and the rest in the rods and that will also cancel the swaying  or yawing movements.

The Southern Q1 with 4 feet  drivers and wide firebox can run and track better at  speed if it had been made that way.

Bulleid knew this locomotve pre WW2 as inspiration.

Nord 141-T

20 minutes ago, 34theletterbetweenB&D said:

 The 2-8-2 mixed traffic formula worked well in all of North America, France and Germany,

Not quite.

The  german 2-8-2 s  were all outlived by 2-10-0s

The last SNCF steam haul was done by a WW1 2-8-0 and the americans went for 2-8-4 and 2-10-4s

48 minutes ago, Murican said:

Yeah, this was what I had in mind when writing up the idea for the Standard 8 2-6-0.

It will be possible to move the shown single 18 inch outside high pressure cylinder ca 200mm forward and we can then allow first driver set 25mm sideway freedom.

Krauss Helmhotz/Zara tracks as well as best boggie.

The single 27 inch low pressure cylinder between frames can be moved a little rearwards if neccesary for max axle load.It can eventually be of the kind Stumpf as tested by Raven my hero.

The wide box boiler can be placed 25-50mm of centre to compensate for removed cylinder.

What livery?

It can do the work of most Pacifics and mineral 2-8-0s?

11 hours ago, Flying Pig said:

 

Unless the designers did something radical, a BR Standard 8 would be very similar to a Stanier 8F or an Austerity.  What were the complaints about the 9F that a loco like that would remedy?

 

Where in UK is 5 times 15.5 tons adhession and flangeless driver better than 4 times 17.5 and a Zara truck up front?

This wonder could better all B1,Black fives and clans and Britaniasas well

And be 10% more frugal and pleasant to man if built as Two cylinder compound with External balance ding

On 13/08/2023 at 13:10, Northmoor said:

I don't think conventional IC engines are anywhere near 60%; the best diesels (very large, maritime) are more like 40-45%.

Big diesels and natural gas engines are plus 50 today.

I have ordered Wild Swan Horwich moguls and look forward to scheme an up to date imaginary version.

Two cylinder compound and low pressure exhaust via Stumpf ports like my hero Raven tried twice.

I have also ordered the Stanier three cylinder 2-6-4 book to see how much space between frames where my low pressure with Stumpf ports shall be.

It seems  all locomotive classes deserve a monograph  and if I may suggest the next, it migth as well be the S3/B16 from NER/LNER in all three variants to grade Raven,Gresley and Thompson.

33 minutes ago, DenysW said:

What puzzles me about large-scale fuel cells is how you get all the oxygen (plus ~80% inert carrier gas if you use air) evenly into the large (vast?) numbers of modestly-sized cells. Easy on a lab scale, but feels like a nightmare on the megaWatt scale.

It gets worse.

The air has to be very clean and efficiency of fuel cells can be roughly 60% on very low power.

Or more or less as modern IC engines.

When fuel cells are stressed efficiency sinks rapidly.

Solution is to collect the oxygen as well as hydrogen from the pyrolisis process,refine both fractions and feed a fuel cell.

Not for my money please

5 hours ago, rodent279 said:

Slightly at a tangent to the thread title, but perhaps related, is a question I've been wondering about.

When GJC built some Saints and Stars as 4-4-2s for closer comparison with the French Atlantics, why did he go to the trouble of modifying the design of a 4-6-0 to remove the trailing coupled axle, and substitute a smaller wheel with outside frames and springs? Why not simply remove the trailing coupling rods? The result is still an Atlantic.

When a disconnected  driver goes out of step(it does) balance will be a disaster

2 hours ago, Compound2632 said:

 

The Midland / LMS compounds, with one HP and two LP cylinders, were designed so that on starting, HP steam was admitted to all three cylinders. Only once the regulator was past the half-way mark did the engine switch to compounding. (That's the Deeley version, the arrangements for the Smith-Johnson engines was a bit different.) Presumably at least some other compound designs working in a similar way, to maximise power on getting underway?

True

I had it mixed up with water release valves that were different on low and high pressure cylinders.

Danish P class atlantics and PR and E classes of Pacifics had safety valves on receiver and combined blow-out and safetyvalves that limited max pressure in low pressure cylinders.

The biggest locomotive cylinder in Europe was the 900mm dia700mm stroke low-pressure cylinder on the Bulgarian 0-12-0 of class 40 and they had max receiver pressure safety valve as well.

5 hours ago, Jeremy Cumberland said:

There's probably not much in it, if you are comparing like with like (3 cylinder simple expansion against 4 cylinder simple expansion). 3 cylinder locomotives need larger outside cylinders, so there's obviously more metal outside the frames. However, there might not be much less metal between the frames.

 

Compounds are different, and a compound will always be heavier than the equivalent simple engine, because of the need for larger low pressure cylinders. Where compounds gain (or should gain, at any rate) is in increased fuel efficiency, not in reduced weight.

Not quite so heavy as the low pressure cylinder hopefully never see so high pressure or temperature as the high pessure one.

13 minutes ago, The Johnster said:

  5' on a modern steam loco with roller bearings and a well-designed means of clearing exhuast steam without it causing back pressure will run very freely and be capable of 90% of steam-age work in BR days.  

Even then, roller bearings and modern lubricants on the slide bars will enable 6' wheels to drive a loco very fast, probably 100mph-capable, and the 5' locos will be able to run at up to around 90mph if needed, but preferably not on a regular basis...

 

 

The driver diameter is not really important if You do some balancing being either three or four cylinders or have strange connecting rod alikes as on the two cylindered Nord141 tank .

Simple two-cylinder locomotives doing more than 5 rounds per second selfdestruct as forseen by my hero mr Raven more than a century ago.

There was a lot of worry with the dragbox design of Britanias and class fives used on fast trains,proving Raven was rigth.

Axlebox type and lubrication in the fifties and sixties was not the issue.

Interesting problem.

A King with a single outside high pressure 22 times 30 inch cylinder driving first driver axle inside coupling rods and sitting up front aside the low pressure of33 inch bore where standard Kings have two inside cylinders, can yield 40000 lbs tractive effort and be measurably more frugal.

How tight line curvature before outside front cylinder collides with rest of world?

Cylinder axis can be 3feet 1.5 inch from midplane.

Mr Riddles ,as pensioner, thougth most locomotives should have had five feet wheels and wide fireboxes according to Steam World issue 144 page 23

8 hours ago, JimC said:

The King boiler was 250psi. 

 

 

You are rigth.

That means the concept of a 2-6-0 as two cylinder compound with a single outside 21 inch cylinder could only muster a tractive effort of 36000 lbs where Kings had 40000 using same formula and fudge factors..