Imaginary Locomotives

[RedGemAlchemist]

On 28/12/2022 at 21:45, tythatguy1312 said:

Frankly it looks brilliant, but it does raise the question of what an unstreamlined A4/W1 would look like

Ugly as sin.

[The Johnster]

A4s have domes and splashers!  Who'd have thunk it!

 

I'm wondering why they bothered with the splashers, as there is no reason I can see that the driving wheels were not simply allowed to run in the open space between the boiler, the curved streamlined running plate, and the streamlined casing.  I can only assume it was to keep some sort of lid on the amount of crud flying around in there at speed on wet days.  Don't forget, when Mallard was coming down Stoke Bank at 126mph, the tops of it's driving wheels were doing 252mph.  The bottoms were stationary of course.

[rodent279]

6 hours ago, The Johnster said:

A4s have domes and splashers!  Who'd have thunk it!

 

I'm wondering why they bothered with the splashers, as there is no reason I can see that the driving wheels were not simply allowed to run in the open space between the boiler, the curved streamlined running plate, and the streamlined casing.  I can only assume it was to keep some sort of lid on the amount of crud flying around in there at speed on wet days.  Don't forget, when Mallard was coming down Stoke Bank at 126mph, the tops of it's driving wheels were doing 252mph.  The bottoms were stationary of course.

No. Relative to the frames, the wheel rim speed will be 126mph, assuming no slip between wheel & rail.

 

[Captain_Mumbles]

On 29/12/2022 at 08:45, tythatguy1312 said:

ah nice, a P1 which wouldn't try to murder the poor fireman. Frankly it looks brilliant, but it does raise the question of what an unstreamlined A4/W1 would look like

I imagine it would look like an A3 with a Vee cab???

[billbedford]

7 hours ago, The Johnster said:

A4s have domes and splashers!  Who'd have thunk it!

 

I'm wondering why they bothered with the splashers, as there is no reason I can see that the driving wheels were not simply allowed to run in the open space between the boiler, the curved streamlined running plate, and the streamlined casing. 

 

To keep any oil thrown up from the journals saturating the boiler insulation. Think Bulleid's and fires. 

Edited January 3, 2023 by billbedford

[JimC]

2 hours ago, rodent279 said:

No. Relative to the frames, 

Please, please, let's not have a frames of reference dispute. They get extremely messy. I see a lot of them in the sailboat world (where admittedly they are both important and very complicated ). 

[DenysW]

  On 28/12/2022 at 21:45, tythatguy1312 said:

Frankly it looks brilliant, but it does raise the question of what an unstreamlined A4/W1 would look like

@RedGemAlchemistReplied (with photo):

Ugly as sin.

 

True as posted, @RedGemAlchemist. But I think most of the ugly is only the support struts for the streamlining. Take those off, paint it blue to match the tender and it would like quite handsome again.

[tythatguy1312]

10 hours ago, RedGemAlchemist said:

Ugly as sin.

I imagine removing the "ribs" and painting it properly would allow it to look substantially better

[Corbs]

Robin Barnes in his book 'locos that never were' pontificated on what a semi-streamlined A4 might look like, with P2 styling.

 

 

Samarti Smith on FB sketched out what a de-streamlined A4 might look like.

 

 

 

[Ramblin Rich]

2 minutes ago, Corbs said:

Robin Barnes in his book 'locos that never were' pontificated on what a semi-streamlined A4 might look like, with P2 styling.

 

 

Samarti Smith on FB sketched out what a de-streamlined A4 might look like.

 

 

 

The de-streamlined version (if that's an acceptable word) really does suffer from the curved footplate making it obvious that something has been removed. The de-streamlined Stanier Coronations looked fine due to the straight footplate. Similarly the P2 style A4 looks far more acceptable.

[Corbs]

22 minutes ago, Ramblin Rich said:

The de-streamlined version (if that's an acceptable word) really does suffer from the curved footplate making it obvious that something has been removed. The de-streamlined Stanier Coronations looked fine due to the straight footplate. Similarly the P2 style A4 looks far more acceptable.

 

 

On the subject of Duchesses, A.N. Wolstenholme sketched out what a semi-streamlined Coronation might have looked like:

 

 

 

For completeness, here was a sketch of a streamlined Thompson pacific from the same series:

 

Edited January 3, 2023 by Corbs

[Flying Pig]

17 minutes ago, Ramblin Rich said:

The de-streamlined version (if that's an acceptable word) really does suffer from the curved footplate making it obvious that something has been removed. The de-streamlined Stanier Coronations looked fine due to the straight footplate. Similarly the P2 style A4 looks far more acceptable.

 

The running plate is not structural and could easily be replaced with something more like a Peppercorn A1.  I doubt the smokebox would survive long in "semi" form either.  You'd probably end up with a Gresley-Peppercorn hybrid in terms of styling: an A3 with a wedge cab and straight running plate open in front of the cylinders.  Having lost the smoke-lifting effect of the streamlining it would probably gain smoke deflectors sooner rather than later.

[tythatguy1312]

1 minute ago, Flying Pig said:

 

The running plate is not structural and could easily be replaced with something more like a Peppercorn A1.  I doubt the smokebox would survive long in "semi" form either.  You'd probably end up with a Gresley-Peppercorn hybrid in terms of styling: an A3 with a wedge cab and straight running plate open in front of the cylinders.  Having lost the smoke-lifting effect of the streamlining it would probably gain smoke deflectors sooner rather than later.

you know, with all the extended complications, I'm starting to see why it was easier to just leave the streamlining on. But it is an interesting aesthetic possibility.

[Flying Pig]

8 minutes ago, Corbs said:

 

 

On the subject of Duchesses, A.N. Wolstenholme sketched out what a semi-streamlined Coronation might have looked like:

 

 

 

 

I think that's very stylish!  I don't think the smoke lifting arrangement would do much though - any chance of Witte deflectors?

 

Edit - the Duchess as originally posted, that is.  The Thompson one is trying much too hard around the cab (but might be improved by curved windscreens, AM9 style).

Edited January 3, 2023 by Flying Pig
A nasty surprise.

[Flying Pig]

1 minute ago, tythatguy1312 said:

you know, with all the extended complications, I'm starting to see why it was easier to just leave the streamlining on. But it is an interesting aesthetic possibility.

 

It's just some sheet metal and brackets to hold it up, not complicated at all.

[rodent279]

I think something like this would sit rather well on a Duchess or on a Bulleid Pacific.

 

 

 

[tythatguy1312]

32 minutes ago, rodent279 said:

I think something like this would sit rather well on a Duchess or on a Bulleid Pacific.

 

 

 

I do believe something similar was tried on a GWR King, though without the central headlamp. The results are certainly a sight to behold.

Edited January 3, 2023 by tythatguy1312

[Compound2632]

3 hours ago, Corbs said:

 

 

On the subject of Duchesses, A.N. Wolstenholme sketched out what a semi-streamlined Coronation might have looked like:

 

 

 

For completeness, here was a sketch of a streamlined Thompson pacific from the same series:

 

 

Engines with their hands in their pockets.

[The Johnster]

9 hours ago, billbedford said:

 

To keep any oil thrown up from the journals saturating the boiler insulation. Think Bulleid's and fires. 

 

[Corbs]

17 minutes ago, tythatguy1312 said:

I do believe something similar was tried on a GWR King, though without the central headlamp. The results are certainly a sight to behold.

 

Interesting alternative take on this published in Steam World Magazine

 

Edited January 3, 2023 by Corbs

[tythatguy1312]

3 hours ago, Corbs said:

 

 

On the subject of Duchesses, A.N. Wolstenholme sketched out what a semi-streamlined Coronation might have looked like:

 

 

 

For completeness, here was a sketch of a streamlined Thompson pacific from the same series:

 

I'd call the designs rather visually unpleasant but I've seen what the French got up to.

 

[rodent279]

14 minutes ago, tythatguy1312 said:

I do believe something similar was tried on a GWR King, though without the central headlamp. The results are certainly a sight to behold.

Yes, I'm aware of those, they look half-hearted at best, nowhere near as impressive as the J class or the 38 class.

[Compound2632]

13 minutes ago, tythatguy1312 said:

I'd call the designs rather visually unpleasant but I've seen what the French got up to.

 

Now those certainly have personality.

[Ramblin Rich]

39 minutes ago, tythatguy1312 said:

I'd call the designs rather visually unpleasant but I've seen what the French got up to.

 

Front of the first one looks very much like an A4's wedge.

The second one looks like it's going to open up like a Bristol Freighter plane!

 

https://www.curbsideclassic.com/uncategorized/rampside-outtake-silver-city-airways-bristol-type-170-freighter/

Edited January 3, 2023 by Ramblin Rich
add link

[The Johnster]

11 hours ago, rodent279 said:

No. Relative to the frames, the wheel rim speed will be 126mph, assuming no slip between wheel & rail.

 

 

Yes, relative to the frames, but not to the ground, which the wheel rim at the top of the circumference relative to the ground will be moving past in a Granthamwards direction at 252mph, and stationary at the bottom, resulting in the axle, which the wheel is turning, moving along relative to the ground at 126 mph, the speed of the train.  You can't even say that the wheel is moving the axle forward, because relative to the axle the wheel is motionless.  Of course the train is descending a bank and has a vertical downwards speed as well; should this be calculated and added to the total?  It starts getting a bit sticky here, because something is either moving the train at 126mph or the train is stationary and propelling the rest of the universe backwards relative to it at 126mph, or some unfathomable mixture of the two, and that's before planetary (moving the train eastwards at about 400mph) and galactic rotation and expansion of the known universe is taken into account.  Even the molecules at the absolute centre of the axle are moving forward relative to the ground at 126mph, but there must be some small portions of those molecule that are not revolving, which is where my brain starts to melt...  You want relativity, ask Einstein, he knows a lot more about it than me!

 

The rest of the wheelset is moving forwards at various speeds averaging 126mph, and revolving at whatever rpm that works out as; the bogie and Cartazzi wheels are revolving a lot faster, but still averaging 126mph forwards, Granthamwards for the purpose of this screed.  As they revolve, the parts that are travelling perfectly upwards and perfectly downwards are moving forwards at exactly 126mph but simultaneously upwards or downwards in balance at a speed determined by the rpm, this speed reducing to effectively zero at the axle central molecules.  The lower half of the wheel is moving forwards at progressively lower speeds and not moving forwards at all at the exact bottom of the revolution, and progressively higher speeds up to 252mph at the exact top of it.  In this way the wheel levers the locomotive along at half the speed at which the 252mph lever at the top of it is moving forwards, 126mph.  The wheel rim, indeed the entire wheel, is as a whole moving forwards at an average of 126mph, but rotationally at a speed determined by the rpm and the wheel diameter. 

 

I prefer the simplest explanations of this highly complex physics; 1) it's magic, and 2) it just does, ok?  So long as it magically continue to just do, things are fine, except that Mallard is attempting to destroy it's middle conrod big end bearing at an average of 126mph forwards and whatever the rotational speed is.  I would hazard that none of these sorts of thoughts were present in Joe Duddington's mind at the time; uppermost, though he never said so, was probably 'how the **** are we ever going to stop!!!'.