Imaginary Locomotives

[Satan's Goldfish]

Helps if I attach the picture...

[rockershovel]

Oh I knew they'd stuffed that in there, my argument was that it was too far from the fire and therefore somewhat cold and there isn't a great deal of point in having a superheater that isn't very warm.

Well, I did say that they didn’t justify themselves... seems to have been an exercise in filling up the available space, rather than achieving the optimum layout.

 

I assume this is why most larger Mallet-type locomotives had those huge “front porches” - because there was no other useful function for the space, which was a result of the necessary running gear overall dimensions

[Regularity]

Why not 2-4-6-0 it 2-4-6-2T?

[JimC]

I don't think you need to incline your inside cylinders quite so much. I reckon this works. (Yellow is of course the inside cylinders. I've drawn the valves under the cylinders, because that was the arrangement on the Dean era 4-2-2s and 4-4-0s, and it keeps it neater. The arrangement of rockers to drive the inside cylinders may be a problem, but lets pretend that clever young Mr Holcroft has worked out something special [grin]. The inside valve spindle isn't parallel to the piston rod, as indeed it wasn't on the 4-4-0s.

 

[later - reworked the attachment to make it (I hope) a bit clearer. I don't know which end the inside valves would be driven from, so have hedged bets.

 

Edited March 5, 2018 by JimC

[runs as required]

Actually, it's a pity that steam development stopped when it did, and the locos built by the Big four didn't advance. I would have liked to see the marine type boiler as used on the hush hush paired up with steam turbine drive as used on turbomotive. I read that one of the problems with the boiler was the pulses from the 3 cylinders upset the firing of the boiler as it had been designed for use at sea with turbines.

In passing by quickly (and without recourse to Google) I had the recollection that this combination was the basis of those Scandinavian condensing locomotives - Hagestrom or some such IKEA name.

dh

[Satan's Goldfish]

Thanks Jim, that certainly looks a much neater version. I'm assuming that is drawn with the wheel con-rod at it's lowest position?

 

2-4-6-0 tender and 2-4-6-2 below with the revised (hidden!) inner cylinders at the front. They look very neat and shorten the overall length a bit when compared with 0-6-6-x versions

[runs as required]

Agree a more elegant front apron.

So why a leading pony wheel rather than the adhesion of effectively 2 panniers under one boiler (and engine crew)

 

dh

[Regularity]

Agree a more elegant front apron.

So why a leading pony wheel rather than the adhesion of effectively 2 panniers under one boiler (and engine crew)

 

dh

The leading pony truck is gentler on the track, and does a better job of guiding the leading section - and hence the rest of the engine - into curves.

 

Think of it more as a “bendy 2-10-0/2-10-2T”, with divided 4 cylinder drive.

[runs as required]

The leading pony truck is gentler on the track, and does a better job of guiding the leading section - and hence the rest of the engine - into curves....

But what kind of speeds are we contemplating with this Behemoth?

Panniers were pretty nippy - even I remember on the tortuous Bala - Ffestiniog.

 

dh

[Dr Gerbil-Fritters]

ooh, look what I found - actual GWR Garratt proposals...

 

 

 

from this interesting website

[runs as required]

How very interesting; thank you.

Dated 1931 - depth of the Depression, poor old Gorton - nothing likely to be forthcoming from someone like Collett at Swindon (where was Stanier when that presentation was made I wonder).

dh

 

Ed

Afterthought - what could the tractive effort have been of the accompanying 4-6-0+0-6-4 Garratt proposal.

That might have got Sir James Milne's publicity sensors excited.

Edited March 5, 2018 by runs as required

[Mr_Tilt]

The 'Super Garrett' on that site is AWESOME!

 

A 2-6-6-2-2-6-6-2 with the front and rear engines arranged as a Mallett under each end of the boiler. More hinges than my kitchen! 

[Corbs]

Previously posted in this thread the last time this came up (thread really does go in circles)

[Satan's Goldfish]

But what kind of speeds are we contemplating with this Behemoth?

Panniers were pretty nippy - even I remember on the tortuous Bala - Ffestiniog.

 

dh

Driving wheels are based on a small prairie rated for 60mph.

[Regularity]

It’s not just the speed, but the length and weight. Replacing the leading drivers with a pony truck won’t alter the tract I’ve effort of the engine, just reduce the adhesion a bit. But it might lead to better distribution of the weight, as that front axle is ahead of any fulcrum, etc.

[Compound2632]

Previously posted in this thread the last time this came up (thread really does go in circles)

MFG-1.jpg

 

I'm sure there's at least one mirror involved here - to say nothing of smoke...

[laurenceb]

the beyer garratt locos and the garratt traction engines are completely un related different companies made in different parts of the country

 

There was a connection between Garratt and Garrett. After the AGE collapse Beyer-Peacock bought Richard Garrett & sons and one of the products made at Leiston works was  mechanical stokers for Garratt locos

[rockershovel]

There was a connection between Garratt and Garrett. After the AGE collapse Beyer-Peacock bought Richard Garrett & sons and one of the products made at Leiston works was  mechanical stokers for Garratt locos

Wow, 10 points for THAT one!

[Satan's Goldfish]

Before I attack my next ridiculous turn of the century kettle, can I just get confirmation on some things: Do Garratts have generally short/stubby boilers? i.e. will the Std 1 boiler as used for the Mallets be ok or do I need to shorten it? And is there something 'not good' with Meyers that means Mallets were more common a design? The Meyer arrangement should have much less overhang.

[Regularity]

The point of a BG is that the power producing plant is slung between the power using units, allowing for a larger boiler within the loading gauge. If you have a Meyer, the power plant has to be above the wheels, to allow the - for want of a better word - power bogies to swivel, raising the boiler centre-line and more importantly, the overall height.

[Joseph_Pestell]

ooh, look what I found - actual GWR Garratt proposals...

 

gwr280-082.jpg

 

gwr460-064.jpg

 

from this interesting website

 

Presumably intended for the South Devon inclines.

 

I wonder if the GWR had actually requested this work or if the drawing office at Gorton was a bit quiet and they decided to pitch an idea to the GWR.

Edited March 6, 2018 by Joseph_Pestell

[Hroth]

Presumably intended for the South Devon inclines.

 

I wonder if the GWR had actually requested this work or if the drawing office at Gorton was a bit quiet and they decided to pitch an idea to the GWR.

I like the idea that there's one proposal for mixed traffic use* and one for goods! I suppose the reason that the GWR wouldn't require such locos would be that they would be a fairly expensive way to deal with Summer Saturdays and be under utilised for the rest of the year. The 2-8-0+0-8-2 might have been of use for the South Wales coal traffic through the Severn Tunnel though.

 

* Wheel diameter of the 4-6-0 + 0-6-4 looks more like a Hall than a Castle or a King.

[melmerby]

Presumably intended for the South Devon inclines.

 

I wonder if the GWR had actually requested this work or if the drawing office at Gorton was a bit quiet and they decided to pitch an idea to the GWR.

According to RCTS the only Garratt the GWR considered was a 2-8-0+0-8-2 machine in the late '20s using 28XX parts but it never went beyond the discussion stage.

I assume BG was pitching for business.

 

Keith

[rockershovel]

The point of a BG is that the power producing plant is slung between the power using units, allowing for a larger boiler within the loading gauge. If you have a Meyer, the power plant has to be above the wheels, to allow the - for want of a better word - power bogies to swivel, raising the boiler centre-line and more importantly, the overall height.

As a general comment of locomotive boilers, it was discovered at quite an early stage that there is a maximum useful length for the actual boiler/firetube section, which is about 21ft. However the boiler DIAMETER can be expanded up to the limits of the loading gauge, and/or the available grate area (to provide the heated gases in the firetubes).

 

A Garratt provides the maximum space within the loading gauge, for the lateral and vertical development of the boiler barrel and firebox. Other things being equal, the Garratt provides the optimum configuration for a boiler, plus various other advantages such as low centre of gravity, freedom to design wheels and running gear without encroaching on boiler and firebox, high degree of flexibility to cope with curves and bi-directional running capability. The main disadvantage is the overall length.

 

The Americans found that within their very large loading gauge, they could accommodate simple-expansion Mallet-type locomotives which had fireboxes and boilers as large as could be made practicable use of, while combining the simple design of the semi-articulated Mallet type AND achieve quite high running speeds, very high tractive efforts and sufficient stability under American conditions.

[runs as required]

Presumably intended for the South Devon inclines.

 

I wonder if the GWR had actually requested this work or if the drawing office at Gorton was a bit quiet and they decided to pitch an idea to the GWR.

I'm sure it would be the latter - it was dated 1931. My wife's very extended family originates from points east of Ardwick Green, Manchester and the older ones all talked of the hard times (there was a much used expression "it's all..[something] at Mather & Platt  - which I remember meant hot air/bullsh1t/noisy rhetoric but nothing actually tangible.

 

When I worked for a BR Design Development Group at Kings+ we were always being propositioned by people such as Dowty (we bought their retarders for Tinsley) and the Bristol Aeroplane Company who had missed the market with their Britannia and were trying to launch a plastic fabricated lightweight train.

 

dh