Lnwr Cornwall as built

[Killian keane]

I have long been interested in this most handsome loco, especially in her original 1847 guise as a 4-2-2, but I have found a few inconsistencies in the few drawings I have seen, namely the two domes seen in this cross section but in no other illustration

Does anybody know where one might find a better drawing or have information on this loco?

[Devo63]

PM sent.

 

Dave R.

[Argos]

Hi,

 

I seem to recall that Cornwall was rebuilt several times in her early existence to try and get her to work efficiently.

It could be the inconsistencies you are seeing are just different rebuilds.

 

You are probably best just picking a source and sticking to it. 

[Penlan]

I have long been interested in this most handsome loco, especially in her original 1847 guise as a 4-2-2, but I have found a few inconsistencies in the few drawings I have seen, namely the two domes seen in this cross section but in no other illustration

Does anybody know where one might find a better drawing or have information on this loco?

 

 '...especially in her original 1847 guise as a 4-2-2'.. This was not Cornwall's original wheel configuration, but for a very short time it was a 2-2-2, with a 12ft overall wb., and a long front overhang. The two outer wheels where 4' 1" dia.,  A drawing in this format appeared in 'The Railway Gazette', 5th July 1918.

The implication for the 1847 rebuild was it became a 2-2-2-2*, the two 3' 6" front wheels (replacing the 4' 1" wheel) not being in a bogie format and a total wb. of 16' 6".

* This my view, not shared by others, but the drawings don't seem to leave enough space for bogie support arrangement.  In the drawing above, this is a centre cross-section, not the outside view of the front wheels.

 

There seems to be various drawings of Cornwall in the 2-2-2-2 format dated to 1847, this is another.  From Ahron's 'The British Steam Locomotive from 1825 - 1925', presumably after the removal of the boiler element around the firebox and either, forgot to draw the dome, or, the dome is set further back..

 

 

This drawing shows the original (double) dome arrangement.  As descriptions state the rear axle was within a tube through the firebox, presumably the water surrounded the firebox and the steam was collected in the dome above, and as the arrows show, moved to the other dome.

 

 

Various Authors have written on the subject over time, including Ahron's and Ted Talbot.  I'm sure there must be a detailed review somewhere in early editions of 'The Engineer', before, or after, the Great Exhibition of 1851.

[Penlan]

re. The front wheels, I wonder if that circle on the frames
between to the two front wheels on the drawing marked Fig 75 - F 
is part of an early form of Mike Sharman's 'Flexi-Chas' 

 

And back to the OP -  a better source? Either NRM or a copy of 'The Engineer' is possible.

Edited December 30, 2017 by Penlan

[Caley Jim]

re. The front wheels, I wonder if that circle on the frames

between to the two front wheels on the drawing marked Fig 75 - F 

is part of an early form of Mike Sharman's 'Flexi-Chas' 

It certainly looks very much like the pivot for an equalising beam of some sort.

 

Jim

[Killian keane]

'...especially in her original 1847 guise as a 4-2-2'.. This was not Cornwall's original wheel configuration, but for a very short time it was a 2-2-2, with a 12ft overall wb., and a long front overhang. The two outer wheels where 4' 1" dia., A drawing in this format appeared in 'The Railway Gazette', 5th July 1918.

The implication for the 1847 rebuild was it became a 2-2-2-2*, the two 3' 6" front wheels (replacing the 4' 1" wheel) not being in a bogie format and a total wb. of 16' 6".

* This my view, not shared by others, but the drawings don't seem to leave enough space for bogie support arrangement. In the drawing above, this is a centre cross-section, not the outside view of the front wheels.

 

There seems to be various drawings of Cornwall in the 2-2-2-2 format dated to 1847, this is another. From Ahron's 'The British Steam Locomotive from 1825 - 1925', presumably after the removal of the boiler element around the firebox and either, forgot to draw the dome, or, the dome is set further back..

 

Cornwall Mk2A.jpg

 

This drawing shows the original (double) dome arrangement. As descriptions state the rear axle was within a tube through the firebox, presumably the water surrounded the firebox and the steam was collected in the dome above, and as the arrows show, moved to the other dome.

 

Cornwall Mk1 #1A.jpg

 

Various Authors have written on the subject over time, including Ahron's and Ted Talbot. I'm sure there must be a detailed review somewhere in early editions of 'The Engineer', before, or after, the Great Exhibition of 1851.

In the second drawing, looking at that small area immediately behind the front axle, where a number of tubes end, would this area not be prone to filling up with ash, rendering the lower tubes ineffective? Or would the draught be sufficient to suck the ash into the higher section of the smokebox perhaps

The rear axlebox is shown in conventional hornguides in the upper drawing, so if this axle is going through a tube in the firebox, the inner diameter of the tube must have been sufficient to allow adequate vertical motion

Also interesting that the (bl**dy enormous!) eccentrics seem to have a set of decorative peircings similar to those in the splashers of a lot of 1840s locos

Edited December 30, 2017 by Killian keane

[Killian keane]

A slight snag has arisen, does anybody know who does an 8' 6" wheel in 4mm?

[James Harrison]

A slight snag has arisen, does anybody know who does an 8' 6" wheel in 4mm?

 

Try a Bachmann "Emily" chassis, I think the driving wheels clock in at around 33- 34mm. 

[Jol Wilkinson]

AGW do a 8' wheel (listed as for a Stirling Single). That's tyre diameter, so add anther 1.0mm for 00/EM flanges and it would be nominal 32mm across the tyre, 33mm across the flanges.

[ian@stenochs]

Also interesting that the (bl**dy enormous!) eccentrics seem to have a set of decorative peircings similar to those in the splashers of a lot of 1840s locos

The eccentrics would be cast so the piercings would be there to make the casting less likely to suffer from contraction stress and voids.

 

Ian.

[Killian keane]

'...especially in her original 1847 guise as a 4-2-2'.. This was not Cornwall's original wheel configuration, but for a very short time it was a 2-2-2, with a 12ft overall wb., and a long front overhang. The two outer wheels where 4' 1" dia., A drawing in this format appeared in 'The Railway Gazette', 5th July 1918.

The implication for the 1847 rebuild was it became a 2-2-2-2*, the two 3' 6" front wheels (replacing the 4' 1" wheel) not being in a bogie format and a total wb. of 16' 6".

* This my view, not shared by others, but the drawings don't seem to leave enough space for bogie support arrangement. In the drawing above, this is a centre cross-section, not the outside view of the front wheels.

 

There seems to be various drawings of Cornwall in the 2-2-2-2 format dated to 1847, this is another. From Ahron's 'The British Steam Locomotive from 1825 - 1925', presumably after the removal of the boiler element around the firebox and either, forgot to draw the dome, or, the dome is set further back..

 

Cornwall Mk2A.jpg

 

This drawing shows the original (double) dome arrangement. As descriptions state the rear axle was within a tube through the firebox, presumably the water surrounded the firebox and the steam was collected in the dome above, and as the arrows show, moved to the other dome.

 

Cornwall Mk1 #1A.jpg

 

Various Authors have written on the subject over time, including Ahron's and Ted Talbot. I'm sure there must be a detailed review somewhere in early editions of 'The Engineer', before, or after, the Great Exhibition of 1851.

Might I enquire as to the source of this second drawing? I've just read Ahrons little piece on Cornwall and if anyone can direct me to relevant volumes of the engineer or Ted Talbots material on her I should be most appreciative

[Edwardian]

Try a Bachmann "Emily" chassis, I think the driving wheels clock in at around 33- 34mm. 

 

Elsewhere here I have seen it quoted as a whopping 35mm

[Compound2632]

In the second drawing, looking at that small area immediately behind the front axle, where a number of tubes end, would this area not be prone to filling up with ash, rendering the lower tubes ineffective? Or would the draught be sufficient to suck the ash into the higher section of the smokebox perhaps

 

I'd have thought the draught through those lower tubes would be pretty feeble, rendering them useless for heating water even if free of ash? The draught must be strongest closest to the blastpipe (not shown on either drawing) - I doubt 1840s engineering was good enough to make the smokebox sufficiently airtight to create anything approaching a uniform low pressure.

[Jol Wilkinson]

I'd have thought the draught through those lower tubes would be pretty feeble, rendering them useless for heating water even if free of ash? The draught must be strongest closest to the blastpipe (not shown on either drawing) - I doubt 1840s engineering was good enough to make the smokebox sufficiently airtight to create anything approaching a uniform low pressure.

The whole concept was pretty novel and somewhat flawed, but it was in the very early days pf locomotive design, so I think that can be excused.

[Jol Wilkinson]

Might I enquire as to the source of this second drawing? I've just read Ahrons little piece on Cornwall and if anyone can direct me to relevant volumes of the engineer or Ted Talbots material on her I should be most appreciative

Mike Sharmans book of a selection of 7mm drawings, "The London North Western Railway"  (Oakwood Press) has three drawings of Cornwall.

 

The first shows Cornwall as a 2-2-2, built in 1847. The drawing is credited to the Locomotive Magazine 1941.

 

The second shows Cornwall rebuilt in 1847 with the 4-2-2 wheel arrangement. This is credited to Locomotive Magazine 1897. This is the drawing in Penlan's post #4

 

The third drawing shows Cornwall as rebuilt in 1858, reverting to a 2-2-2. Shown with an "!open cab", this looks very much as she finally appeared with the Webb style cab and as provided in the the 4mm kit. This drawing is also credited to Locomotive Magazine 1941.

 

Ted Talbot's "An Illustrated History of LNWR Engines" has these photos, the cross section shown plus the cross section in post #4 and also a more detailed cross section and a drawing of its original tender. There are six photos, a WD  and outline drawing of Cornwall in later Webb condition with a 1500 gallon and then a 1800 gallon tender. There isn't much detail in the text other than general history.

[Killian keane]

Thank you very much gentlemen, I di have a knack for choosing oddities to model (fire queen is my other dream magnum opus) as far as I can fathom only two engines with the boiler below the axle were built, Cornwall and L'Aigle, but a third design, an 0-4-0 was proposed thus:

[stephi]

Hello 

I have two questions, my first one is about this drawing of the Trevithick 4-2-2

it is on the 2-2-2 version

I Wonder what is the use of the apparatus pointed on my picture, it is the break ?

if yes do you know where I could find a good schematic of such thing?

I want to model it but I only find side picture 

 

my next question Do you have more information

about this proposal of a 0-4-0 engine ?

Thanks very much for your help

 

[RLWP]

The mechanism ringed looks like the lifting links for the valve gear

Locomotives of this era rarely had brakes

 

Richard

[stephi]

Thank you Richard :)

 

I hope, one day  to be able to  model this loco in the most accurate way possible :)

 

[RLWP]

6 minutes ago, stephi said:

Thank you Richard

 

I hope, one day  to be able to  model this loco in the most accurate way possible

 

 

"in the most accurate way possible" is an interesting idea. As there is so little information, you could do almost anything within the dimensions of the very few drawings, and it's unlikely anyone could prove you wrong.

 

Or you could do a huge amount of research about early locomotive design in general, and for Crewe specifically, and still end up with something that it is unlikely that anyone could prove you wrong (or right!)

 

Did you make any progress @Killian keane ?

 

Richard

[stephi]

to be honnest I only find side view or schematics of the loco in the 4-2-2 and 2-2-2 version. and yes I'm doing research about the whole work of Crewe , its still helpful.

ny exemple I will use certain part of the 2-2-2 columbine from Crewe for the front and aft part I can't see

I know that anybody could prove I'm wrong, but I want to be "near" the reality. since it a personal project  I'll do my best :)

but if people can prove I'm wrong will I'm doing with the few little information I can find, I can also ask "what information you have to prove I'm wrong"  In this case it's mostly it could be best to use the word " interpretation " and not model of the original engine 

 

Edited March 16, 2019 by stephi

[stephi]

I believe I have finaly find the solution to the valve gear   you was true about it.  thanks !

but If what I "believe" is true  I also understand why it was rebuilt in 1858... very unpractical to have all the gears over the boiler,  (I also imagine the driver having to concentrate on is job wile he can see everithing Moving "on" the loco )

 

by the way sorry to everyone who read my texts. my English is not really good 

[Killian keane]

2 hours ago, RLWP said:

 

"in the most accurate way possible" is an interesting idea. As there is so little information, you could do almost anything within the dimensions of the very few drawings, and it's unlikely anyone could prove you wrong.

 

Or you could do a huge amount of research about early locomotive design in general, and for Crewe specifically, and still end up with something that it is unlikely that anyone could prove you wrong (or right!)

 

Did you make any progress @Killian keane ?

 

Richard

Im waiting to see if any more info or drawings come up before starting on a model,  I have plenty to do in the interim!  

[stephi]

This engine fascinate me (Don't know why)  its why I want to built it  

I modeled one about 10 years ago for a N gauge railway, but to small , no informations  and poorly made, the next one will be better, and yet, if anymore information appear I will be able to modify it

 

by the way @Killian keane  I found for the first time the 0-4-0 schematic on you post  do you have more informations about this proposal ?  it look so odd with those big Wheel 

 

thanks