Carriages / Wagons for Locomotion No.1

[What About The Bee]

The Examiner published notice of the opening of the Stockton and Darlington Railway. Issue No. 924 Monday, October 17th 1825.

You will find the notice here.

https://babel.hathitrust.org/cgi/pt?id=hvd.32044089261531&seq=675

While the obvious plagarism of the consist is present, referencing the "elegant covered coach", we do have pertinent details about the passenger carriage, underscored.

"The coach in which the proprietors travelled is to ply the road from Stockton to Darlington". We have seen advertisements of this service in an earlier post in this thread. 

"From the success", observed The Scotsman, "of this experiment at Darlington, and from what we have learned otherwise, we have no doubt that when the Edinburgh and Glasgow Railway is formed, STAGE-COACHES moved by loco-motive engines will commence plying at the very first..."

Stage-coaches. The very name of a particular vehicle in England the 1820s.

Bee

[What About The Bee]

https://babel.hathitrust.org/cgi/pt?id=iau.31858045867771&seq=223

New England Farmer, dated January 24, 1826. "In consequence of the opening of the Stockton and Darlington Railway, it is said that the price of coals of the former is reduced from 18 to 12 shillings per ton. Goods are transported at one halfpenny per ton per mile. A COACH has been established on the rail road which carries passengers at one penny a mile"

https://babel.hathitrust.org/cgi/pt?id=umn.31951p01084278u&seq=586

The Monthly Magazine November 1826. "There are six or seven COACHES now running on the Stockton and Darlington Railway. They carry on average 150 passengers a day. The charge is 1d. per mile outside, 1½d inside" 

While it is possible that the Smiles illustrated carriage had inside passengers, I see no accomodation for outside passengers. Again, the reference here to a coach.

As a reminder, there was an advertisement for a railway coach. Here is the view of Union, which offered fares of 1d. per mile outside, 1½d inside.

Perhaps you still wish to have Locomotion No.1 pull the 1860s Smiles illustration, which has popularly entered the public consciousness via the centenary celebrations and the replica at Beamish. I totally understand that. It simply is not supported in the record, an invention of Smiles.

Hornby should offer that version, simply to match the myth.

Yet, Longridge's illustration matches all the period advertisements and descriptions. It is a "coach". Not a box on wheels. Hornby must produce this carriage, to be pulled in consist, as Longridge shows.

Bee

[What About The Bee]

Earlier in this thread, I linked https://books.google.com/books?id=0qdVAAAAcAAJ&printsec=frontcover, an 1827 book which preserved an earlier 1825 article about the Opening of the Stockton and Darlington Railway.

While the book preserved the text of the article, I was left wanting. This was merely the text. What did any newspaper look like from nearly 200 years ago, and more specifically, that of the Newcastle Courant of October 1, 1825?

[instructions and Key:

Right click, "view image". Zoom.

Lower Right, full front page.

Top, banner with date.

Lower Left, fully legible text, when zoomed.]

While I was hopeful, there is no further information other than the article preserved in the 1827 book. There are no images of the railway, the locomotives, the participants or the scene. Yet it is the most contemporaneous notice to the Opening, in original presentation. What you would see that day, reading the news, nearly 200 years ago.

The novelty! Extra! Extra! Read all about it!

Bee

[What About The Bee]

A NEW CANDIDATE EMERGES

Point 1.

The Science Museum has a letter from John Backhouse to his sister. 

https://collection.sciencemuseumgroup.org.uk/documents/aa110075124/letter-from-john-backhouse-to-his-sister-describing-the-opening-train-on-the-stockton-darlington-railway

You may, of course, read all the details there. The museum dates the letter as 27 Sept 1825. Note the post mark, 1825, irrefutable.

To summarize, John was a spectator at the opening, aged 14. He wrote to his sister, describing the event, and most interesting for our purposes, drew a sketch of the train to include "Experiment", numbered 22 in his diagram. One may term this a childish sketch, lacking in detail given the size. But please read this post in totality before formulating an opinion.

He also states that the flag in chaldron behind "Experiment" reads

'Periculum privatum' and 'Publicum Bonum'. This presents as a unique data point, a possible correlation.

Point 2

The Science Museum holds non-period art by John Dobbin.

https://collection.sciencemuseumgroup.org.uk/objects/co227670/opening-of-the-stockton-darlington-railway-ad-1825-from-a-sketch-by-the-artist-at-the-time-drawing

 While the image is clearly from 1871, it is claimed by the Friends of the Stockton and Darlington Railway that Dobbin was a spectator at the event, aged 10. 

The consist is drawn, again very small. 

Point 3

We have a verbal description of "Experiment, from the Durham County Advertiser, dated 1 Oct 1825. You may read the entire transcript here

https://www.sdr1825.org.uk/archives/durham-county-advertiser-1-october-1825-transcribed-by-peter-bainbridge/

Extract:

This coach, named “The Experiment,” is fitted up on the principle of what are called the long-coaches, the passengers sitting face to face along the sides of it. It is calculated to carry 16 or 18 inside, and is intended to travel daily for public convenience between Darlington and Stockton.

Further:

A flag inscribed – “Periculam Privatum Utilitas Publica,” which may be rendered into English thus Private Risk for Public Utility.

Point 4 Correlation

I have clipped the sketches of Backhouse and Dobbin, made them equal in size. Presented here for your inspection

A few things are immediately apparent

1) They look to be the same!! 5 openings. 6 poles. Box like. In the Dobbins image, the passengers are facing inward, as the Durham County Advertiser describes. Yet, how can this be? The Backhouse letter was a private communication to family. Dobbin could never have seen it. The "Experiment" as drawn by both, show identical features. The correlation? Both were 1st hand spectators

2) There is something written in large bold letters beneath the openings on both images. The Backhouse image suggests it reads "Experiment". Spell the word carefully, and see the letters in Backhouse's sketch, one at a time.

The illustration by Dobbin is not legible.

1) The reason I couldn't read the writing on the flag in the Longridge engraving is because it was in Latin. I was expecting English. Upon further inspection of the Longridge engraving, there is correlation with the S&DR motto.

In the case of Backhouse, he proves himself a 1st hand spectator, by referencing the Latin in the moment, albeit incorrectly.

2) The general shape is consistent with the 1860 Smiles illustration.

Yet in detail, it is not a match. Only 3 openings, not 5 as drawn by 2 firsthand spectators. Walls, not poles. No writing on the side. It would be consistent with the Durham County Advertiser description.

3) The period advertisement for Experiment does NOT mention fares both inside and outside. Just one fare, 1d./mile. If seating was available inside AND outside, there would be a fare differential.

4) The Longridge engraving can only be dated as early as its publication. 1832. It is possible that the artist presents "Experiment" as per the period advertisement illustrations, an anachronism. Just a suggestion, not a fact.

5) Durham County Advertiser describes 16 or 18 passengers, facing each other. Coach seating is facing each other, yet it would be impossible to seat that quantity of persons in any stage coach. We know from the LMR, that similar compartments hold 6 persons, not 16.

CURRENT RANK

1) In primacy of place, the "Experiment" as sketched by 1st hand spectators. They independently provide the same data points. The sketch is consistent with all of the data assembled so far, most importantly with each other, but also with the Durham County Advertiser.

2) Falling to second place, the stage coach illustrated in the Longridge engraving. Consistent with illustrations in advertisement of passenger service. Near period illustration, yet perhaps not 1st hand spectator. Accurate in many other details, such as flags and Locomotion/Active valve gear. 

3) Dropping to last, the Smiles illustration. Far from a period illustration, can only be dated as early as 1860. Consistent with the Durham County Advertiser verbal description, but utterly fails to match details provided by independent 1st hand spectators.

[What About The Bee]

I wrote to the Friends of the Stockton and Darlington Railway, sharing the link to this thread.

I have heard back from them and this is what they had to say

÷÷÷÷

The new replica Experiment is built and being painted at present. We've tried to make it look as accurate as possible but for modern use it has had to have side opening doors (concealed) and a slightly later design of wheel. (it also hides air brakes and variety of other things underneath the original never had!). Metal roof rails for guard and baggage which can be discerned in the Backhouse/Dobbin images may not make the final build sadly for practical reasons. No official photos of it yet, but one of our members spotted it during an open day at the A1 trust workshops where it is being painted after being built by North Bay Engineering in Darlington.

÷÷÷÷

You will note: The Backhouse and Dobbin images, the 1st hand spectators. The researcher has independently arrived at the same conclusion I have.

Further, this link was shared, of the current state of the build for the S&DR 200th Anniversary.

https://www.facebook.com/groups/sdr1825/permalink/2676405032497776

The researcher went on to say:

Great if Hornby could turn out an accurate Experiment and chaldrons for 2025, North Bay Engineering do have CAD drawings for the replicas and I'm sure would be happy to help if needs be.

÷÷÷

MODERATORS: Can you somehow get this in to Martyn and or Carl? This is an amazing offer. The CAD drawings of the replicas will make any Engineering work at Hornby lighter. The Friends of the S&DR are making a wonderful offer.

Bee

[What About The Bee]

From the Facebook Post by the Friends of the Stockton and Darlington Railway

Bee

[What About The Bee]

Throughout this thread, we have examined several candidates and finally arrived independently at the Dobbins/Backhouse images, just as the researcher at Friends of the Stockton and Darlington group did.  The solution for both researchers identical.

With Locomotion No.1 edging closer, we all would like some rolling stock to go with the locomotive.  Of course, Accurascale's chaldrons are perfect for this.

But what if you wanted the passenger carriage Union or Defiance? We have Longridge's wonderful print, showing this carriage type in consist.  What other waggons are in that consist?  Chaldrons.

What if you wanted the passenger carriage Experiment, as illustrated by Dobbins and Backhouse.  Wonderful drawings, with the carriage in consist.  What other waggons are in those consists?  Chaldrons.

Therefore, to properly scale those passenger carriages, they should be modeled in reference to a standard, to wit: an Accurascale Chaldron.

To that end, I've reverse engineered and sketched up an Accurascale Chaldron.

No details.  No split spoke wheels.  No flanges.  Just a basic chaldron, unadorned.

The standard candle, defined.

Bee

[What About The Bee]

Have you ever wondered how a model is developed?

Here is how I begin any CAD design, with the analysis of the existing imagery and descriptions.

We have two portrayals of Experiment and one written description, which informs us of the seating chart and carriage entryways.

Of the two images, we have the one by John Backhouse, drawn on the spot on 27 Sept 1825.  The other is a more formal painting by Dobbins, who was a first hand observer.  Unfortunately the painting itself was created decades later.

Of the two, I personally consider the Backhouse depiction far more important.  Why?  Backhouse had nothing to reference, no other railway comparisons.  He drew what he observed, without consideration of what he "knew".

For example:  Backhouse depicts Experiment with FOUR axles.  That is a most unusual characteristic, observed again only briefly for the Duke of Wellington carriage on LMR Opening Day; but usually not observed.  Nearly everything had only two axles¹. Four axles presents an issue.  Backhouse cannot know the difficulty.  He has nothing to base his depiction on, no prior knowledge of railways.  Thus, he drew what he observed.  Four axles.  

What does Dobbins depict, decades later?  Nothing.  He conveniently hides the chassis behind a wall.  Now that could have been an accidental depiction. It also could have been deliberate.  It could also be an artist, knowing that four axle carriages have railway issues, doubts his own recollections and so avoids the dilemma by hiding it.  

My CAD of Experiment must therefore have FOUR AXLES, as per Backhouse

How long should Experiment be?

I measured the top of each chaldron depicted by Backhouse.  The average length was just over 21 pixels.  I then measured the top of Experiment, as depicted, obtaining 51 pixels.

Therefore, the ratio is 51/21.2 = 2.406

I measure the top of the Accurascale chaldron at 33.7 mm.  OO Experiment should be 81.071 mm long.  

What about Experiment's wheels and axles?

Here, there are some dilemmas.  

Backhouse shows a chaldron hopper length and wheel diameter.  Accurascale also has these characteristics.  Yet between the two, there are different ratios. 

Further Backhouse shows both chaldron wheels and Experiment wheels.  There is a clear size difference.   The ratio, per Backhouse, is 1.57.  That is, Experiment's wheels are 1.57 times bigger than his chaldron wheels.

If I am to keep the ratio of Accurascale chaldron wheels to Experiment wheels correct per Backhouse, then the wheels should be 18.56 mm in diameter. Obviously too big as that is a scale diameter of nearly 4 feet 8 inches. 

Yet I should make Experiment's wheels bigger than the wheels on an Accurascale chaldron.

What else pops off the page?  

These points are agreed upon by Backhouse and Dobbins.  

1. There are 6 posts per side, creating 5 openings.  

2. "EXPERIMENT" is written on the side (presumably both sides?) in bold capital letters.

3. No horn guides or blocks are shown.  The wheels must be outside of any frame and the bearing surfaces inside the wheels.

First pass at CAD for OO Experiment.

Experiment's chassis shown with four axles and larger wheels, next to a chaldron for comparison.  Yes, the track radius is a concern with this.

And herein is another dilemma

Does the carriage body nestle in between the wheels or does it overhang the wheels?  

Horse Drawn Omnibus Images

If between the wheels, as all the imagery suggests, that is very cramped internally.  We must fit two of: seat depths, external walls and wheel clearances plus one central walkway.  All of which must be inside 4'8½".  Made all the worse by the OO Squish problem.  This image shows a scale 12" depth seat on each side, with a grand total of a scale 6" walkway.

Or with overhanging, we have a more spacious and reasonable cross-section.  The seats have ~16" depth (normal) with a much more reasonable walkway between them.

I think that's enough for now.

Bee

¹Stephenson's Patentee LMR33.  The 1834 patent explicitly claims flange-less wheels as a method of overcoming multiple axles.  Therefore, it cannot apply to Experiment, created in 1825.

Edited May 17 by What About The Bee
Emphasize Paragraph heading

[LTSR_NSE]

Could 2 adapted Chaldron chassis (with some kind of pivot between) have been used? (akin to the later log wagons & Duke of Wellington coach on L&MR)

If your undercut/overhang body is prototypical, that could possibly allow a small degree of pivoting? (alternatively 4 independently pivoting axles would allow curves to be negotiated with even smaller degree of pivot per axle)

That suggestion is probably anachronistic for the period - but might assist with oo compromises & R2/1 curves?

Edited May 17 by LTSR_NSE

[What About The Bee]

@LTSR_NSEExcellent observation.  The LMR log waggon completely slipped my mind, and yes, per Whishaw (1842), it clearly had a pivoting member.

Both Backhouse and Dobbins show the top of the seat backs terminated at the height of the chaldron.  The seats I illustrate in the prior post are merely for width and are much too low.  Once raised, there will be significant room underneath the false floor.  Does it conceal a pivot?  I do not know the answer. 

Let's follow the data, and see where it takes us.

Bee

[What About The Bee]

PART ONE, Carriage Body Width

When this topic was last visited, I expressed some alternatives as to the width of the carriage body.  Did it nestle betwixt the wheels or did the carriage body sit over the top of of those wheels?

Let us revert to the data presented to us in the Durham County Advertiser, dated 1 October 1825, mere days after the S&DR opened.

This coach, named “The Experiment,” is fitted up on the principle of what are called the long-coaches, the passengers sitting face to face along the sides of it.  It is calculated to carry 16 or 18 inside, and is intended to travel daily for public convenience between Darlington and Stockton.

There are two other data points to consider, both of which are human factors.  The minimum width of a walkway should be 24" and the depth of a seat should be 17¼".  These data points can be readily confirmed on the internet.

Suppose the carriage body sits in between the wheels.

Arithmeric Exercise One:
Add up everyrhing but the aisle, to see how much would be left for the aisle. 

Track gauge 4'8½" = 56½"

Flange thickness (from DOGA) 2.19" × 2 = 4⅜"

Wheel clearance to carriage 2" × 2= 4"

Wall thickness 3" × 2 = 6"

Seat depth typ 17¼ × 2 = 34½"

Sum 48⅞"

56½" - 48⅞" = 7⅝"

An aisle should be sufficient to walk in.  7⅝" is not a sufficiently wide walkway , especially in a long well as deep as the height of a chair seat, roughly 20" deep.

Arithmeric Exercise Two 

Suppose I guarantee a standard walkway; how deep are the seats?

Per the internet, the minimum walkway width for one person is 24".

[Both sides) Flange+Clearance+ wall thickness  = 14⅜"

Add the aisle @24" = 38⅜"

Subtract from track gauge
56½" - 38⅜" = 18⅛"

Divide by 2, as there are two parallel rows per the Durham County Advertiser.  9¹/₁₆" seat depth.  That is a very shallow seat indeed.

Arithmetic Exercise Three
Now suppose I permit the carriage body to overhang the wheels.

Aisle 24"
Seats 17¼ " ×2 = 34½"
Walls 3" × 2 = 6"

24" + 34¼" + 6" = 64½"

Nicholas Wood, 1853, states 1825 S&DR rail was malleable (wrought) iron, 28 lbs per yard.  The French text translated the word as "wavy", meaning fishbelly rail.  This is consistent with the Longridge illustration, which shows fishbelly rail.

Width of 28lb rail 1¾" × 2 = 3½"
Gauge 56½"
56½" + 3½" = 60"

To have standard seating and standard walkways, the carriage overhangs the outside of the RAIL by 2¼" per side.  Less than 1mm in OO.

Conclusion #1: I think this finally puts paid to the "shed on wheels" illustration that is often proffered as "Experiment" in Smiles of 1863.

Not only is the illustration nearly 40 years out of date, the numbers illustrated here preclude this from consideration.  Either the aisle is far too narrow or the seats are far too shallow.   

We must consider that public transportation was available in 1825.  Horse drawn coach advertisements abound in the press, and these had seats and aisles.  The public would expect similar accomodation from the S&DR.

Conclusion #2: "Experiment" has a carriage body which overhangs the wheels.

PART TWO: Carriage body elevation

From John Dobbins, we know the seat back came up to approximately the middle of passenger backs.  Human factor engineering says the top of our heads are ~36" over the seat.  ½ way up is 18".  Further, that the top of the seat back is nearly exactly the height of a chaldron.  

From the internet, we can see that the height of a chair seat is just over 20 inches.

From these data points, as can assign elevations to a carriage body seating unit.  It now has this appearance.

Of note is the incredible gap between the chassis and the carriage body.   But in following the known datapoints, the CAD model must remain true.

This could easily accommodate a bogie arrangement.  The four axle arrangement begs the question.  Yet we find no notice of bogies in until the aquatint of the log waggon on the LMR, 1834.  The Duke of Wellington carriage may or may not have had bogies .  An interesting theory, but we simply do not know.

Instead of assuming a bogie arrangement, in the absence of evidence, I will keep to a rigid chassis, without bogies.

PART THREE: Going around Second Radius (or indeed any radius) Curves.

Simply put, lateral compliance, permits multi-axle travel around a curve. Nearly every steam locomotive in your fleet performs this magical feat.  The side to side play permitted is a function of the track radius of curvature, the wheel diameter, the flange height and the longitudinal axle distribution on the locomotive.

Equation One: Wheelbase extension via flange height.  

Equation Two: define lateral play as a function of true wheelbase.  Y is the side to side play required.  M is the nominal wheelbase.  X's are leading and trailing flange wheel base extensions

In order to reduce friction and permit easy side to side motion, it is a good idea to use brass axle bushes.  All of these require a good working knowledge of the dimensions of the exact parts.  I have assumed some numbers, so as to get an initial idea of the feasibility of the design.  Frankly put, it is feasible and the equations I wrote check against FreeCAD.¹

I've placed the order for the exact parts.  The parts are coming from the UK.  I will definitely adjust the design and publish my final numbers once I have a firm measurement of the parts. 

Here, I show the chassis and axles, within the lateral compliance designed, on a second radius curve (R2).

PART FOUR Carriage Decoration

I've added Experiment to the side of the carriage body.  Given the Dobbins illustration, I think there is a half round molding at top and bottom, suggesting that the letters are raised.  Thus, I have made this part of the CAD.

The superstructure consists of the posts and roof.  

PART FIVE.  The Cradle.

The cradle, that supports the carriage body seating unit is entirely speculative.  Backhouse does not draw a single chassis for any member in the consist.  Dobbins hides the chassis behind a wall, as previously discussed.

But the seats cannot float over the chassis like a blimp.  I've designed a simple cradle that would support the seating unit and transfer the passenger load down into the chassis from the seating unit. 

That's enough for now.  Next update when wheelsets and bushings arrive.

Bee

¹Yes, I wrote my own equations. There are other ways to solve for these values.  I prefer trigonometry.
 

Edited May 25 by What About The Bee
Word choice

[Aussie Fred]

Looking at The "Experiment" Railway Coach, one wonders why they bother when a horse drawn carriage on Road would be more practical and wouldn't the horse have trouble stepping over/through the sleepers?

[What About The Bee]

Hi Fred

No worries about answering your questions.  It's always better to ask and find out the answer.

1 hour ago, Aussie Fred said:

 wouldn't the horse have trouble stepping over/through the sleepers?

The only part of the rail system that was exposed was the top of the rails, with just enough clearance for the flanges.  The remainder of the system was buried under hard packed earth.  This means, unlike a modern system, the top surface between the rails was a dirt path!

This even more so with stone sleeper blocks.  The rectangular stones (24" wide × 24" long × 12" thick) were sub-grade.  There was no tie between the rails.  

Horses would have an issue with modern rail.  

1 hour ago, Aussie Fred said:

, one wonders why they bother when a horse drawn carriage on Road would be more practical 

In a word, rolling efficiency.  The same answer in 1825, 1925 and next year, 2025.  Pulling something on rail is much more efficient that pulling that same thing on a road.  

So either increase the load or decrease the energy required.  A horse could easily pull Experiment or Defiance on rail, fully loaded.  Much greater capacity than the road stage coach.

Period roads were not smooth asphalt or macaddam.  They were cobblestones in the city, dirt roads in the country. 

Period newspapers reported that as soon as a railway was established, the road stagecoaches went out of business.

Bee

Edited May 25 by What About The Bee
Macaddam, not macadamia. Sheesh

[LTSR_NSE]

Only once steam locomotives became capable of entirely replacing horses (& also heavier, requiring stronger rails and more stable fixings) did sleepers become more commonplace.

Edited May 25 by LTSR_NSE
Removed duplication of Bee’s reply

[What About The Bee]

Hi LT&SR_NSE 

A goodly portion of the LMR was originally laid in sleepers, Chat Moss in particular.  Understandably, burying a sleeper subsurface was asking for rot to occur.

One answer was wood preservation.   An 1832 wood preservation patent by John Howard Kyan became known as Kyanized Wood.  The LMR did apply for a license from Kyan, and used it in sleeper production by 1837.

The entire rail support issue was a problem.  The fundamental competition to wooden sleepers was stone blocks.  Stone blocks provided a stiffer ride, so much so that broken blocks were common.  In 1836, it was reported that a single 100 yard stretch of track by the Edge Hill Engine Works had 200 broken stone blocks!  All of which needed replacing.

To the stone block vs wooden sleeper conundrum, add in the fishbelly vs parallel rail issue.  Which was better?  That actually wasn't a clear cut answer in the period.  

The cherry on top being that all of the rails were entirely too light.  The S&DR opened with 28 lb per yard rail.  The LMR opened 5 years later with 35 lb per yard rail, a 25% increase.  By the end of the 1830s, 70 lb per yard rail was already in use, a 250% increase.

You are correct in my view.  As heavier parallel rail with heavier fixings, with improved wood preservation and drainage came into being, heavier locomotives pulled heavier loads.  The horse was banished.  No need to worry how the horse would do.

Bee

[What About The Bee]

As a curiosity, here are some early Stockton & Darlington Railway rail profiles.

I have yet to find a profile of the rail in use in 1825.  Drat!

Bee

[What About The Bee]

With the parts on hand, the final bits of OO Experiment can be resolved.  The parts that were reverse engineered (guessed at) were measured and updated.  

The model was updated to permit OO Experiment around a 2nd radius curve (438 mm).  You may read all about that here: Round The Bend

Another update is couplings.  It is clear that Locomotion is to run with the Accurascale Chaldrons.  Carl stated as so, during a video update.  The Accurascale Chaldrons come with extra magnetic chain couplings to attach to other rolling stock.  They use a NEMA 362 pocket.  I've installed that pocket, to spec, on OO Experiment.  It is rendered as a separate color, as separate part in CAD, but in the 3D print, it will be fused with the chassis

When Locomotion No.1,  Accurascale Chaldrons and OO Experiment are coupled, it will be the same coupling throughout.

I decided to install side skirts under the seats, outboard of the seat cradles

The reason is apparent. John Backhouse was a first hand observer on Opening Day of the Stockton and Darlington Railway. When the CAD is viewed in side elevation with the chassis detail turned off, as Backhouse depicts the consist, something very magical happens

Bee

1) Hopefully, this goes to the correct thread.  Posted via search function

2) Would someone mind examining the metadata for Locomotion?  I'd like to have OO Experiment on hand when Locomotion arrives.  Thanks!

 

Edited August 3 by What About The Bee
Spelling

[LTSR_NSE]

47 minutes ago, What About The Bee said:

Would someone mind examining the metadata for Locomotion?

Current ETA is 22 Oct ‘24

(be aware that in interviews/Q&As Martyn & Carl have only ever stated “end of the year 24” for Locomotion projected arrival - so treat website ETA with caution!)

[Peter Stiles]

I'm hoping, one day, to be able to buy a book full of Bee's wisdom. It'd be well thumbed and look great on a shelf. I've not learnt so much since Duke's posts of days gone by...

[What About The Bee]

That is very complimentary @Peter Stiles.  While I do appreciate the sentiment, it may be unwarranted.  I'm always in awe of those around me and strive to do better. Thank you.

I share your enthusiasm for learning.  Nothing like a new discovery, a novel approach, to invigorate the mind.  I came to the Forum so as to learn from others who are more knowledgeable than I about model railways. There are plenty.

I make plenty of mistakes, but writing a book will not be one. 😁 

Bee

[threelink]

Shame, Bee. I too would relish the prospect of a book. 

[What About The Bee]

But @threelink, why would you want a book?  A book is a static store of information, there is no spirited conversation.  

Books are great.  But conversation is better.  Here, we can trade ideas.  There, its the world according to some nutter named Bee and no, thank you, the world does not need that diktat.

Bee

 

[threelink]

Agreed that conversation is better but one cannot reasonably start a conversation at, say, 2am but one can sit and read a good book. 

[What About The Bee]

I've been doing some research on Active, the "original" version of Locomotion No.1.  I think it quite enthralling, so join me.

George Stephenson's first locomotive was Blucher, inspired by Blenkinsop's cogged engine.  Linkage between axles, similar to Blenkinsop, was via gears.  Wood, Practical Treatise, 1825 shows us only Blucher's gear train.

The issue, of course, is gear wear.  Exacerbated by imperfect control of axis of revolution due to imperfect bearings.  George swiftly realized that this was not the answer.  

On 28 February 1815,  Stephenson and Dodds received UK patent number 3887.  

One of the basic claims of this patent was that the locomotive would be driven strictly by the adhesion between the wheels and rail, not by cogs (as in Blenkinsop).  This is how a locomotive works.
 Patented!

With two central and vertical cylinders, each axle has the same quartering.  The quartering is not different from side to side.  Rather the quartering is by axle, not by side.  Thus, the other part of the patent described how the front and rear axles were to be coupled to retain quartering.  The primary patent drawing shows the arrangement, but the text makes it clear.  The axles could be crank axles, with a pair of coupling rods between axles.  The patent drawing also specified a chain linkage between axles as an alternate method.

"The engines are kept at their proper distance apart [quartering].... two grooved wheels that have notches into which the projecting bolts of the endless chain fall, and in which it works, are fixed in the centre of each axle."  

We have this magnificent sketch.  Per the Science Museum, drawn by George Stephenson, himself.  

It too shows the chain coupling system, in this case the chain isn't perfectly stretched, rather it has some slack.  Chains normally wear, making this is a likely operating condition.

In 1817, with Losh, Stephenson patents the steam spring.  The feature was to suspend the locomotive using a series of pistons and steam.  While the steam spring was not well accepted, we have the patent drawing which shows a coupling chain.  Notice, no coupling rods, no cranked axles.

Next, we have George Stephenson at the Hetton Colliery.  Early 1820s.  There is a marvelous aquatint labeled Hetton Colliery, showing a locomotive 

Again, there is the chain coupling.

There are two other views of a Hetton Colliery locomotive, included here.  While we cannot make out the chain, it is most certainly there.

We have this drawing in Tredgold, 1825.  A Hetton Colliery locomotive.

Chain coupling

Wood, 1825

Chain coupling

I hope by this point in the discussion, you have accepted that the chain coupling was more than a one off experimental system.  We have depiction after depiction, with the chains clearly visible.  

And then we come to the Stockton and Darlington Railway.  A mere 2 years after the Hetton Colliery locomotives.   The contract was let to Robert Stephenson & Co in July 1824.  We know the partners were George, Michael Longridge of Bedlington Iron works and Pease, the railway promoter of the S&DR.  Industrial giants of the day.  George had divested himself of the company, to work on the LMR.  Robert was off to South America.  So as the two locomotive principals were off in the weeds, it was up to Longridge to deliver the first locomotive to the S&DR, to wit, Active [Locomotion No.1].  

Per the excellent paper:  "LOCOMOTION No.1 An Assessment of its History and Modifications Through Archaeological and Archival Study"  Bailey & Davidson; 2023, the S&DR was pressuring Robert Stephenson and Co to finally deliver on contract.  The authors state that
"Stephenson thus found himself under intense pressure to complete the Active as a reliable locomotive by that time. It is therefore most likely that the first boiler, with the yet unworkable parallel motion, was laid aside and substituted by the yet unfitted boiler for the second locomotive. He would then, most probably, have fallen back on the well-proven ‘Killingworth’ type arrangement of slide-bars and crossheads, whilst introducing connecting and coupling rods, and abandoning the use of ‘steam springs’."  The authors of the 2023 paper make much of internal to the company sketches.  They show coupling rods, tis true.  And certainly, parallel motion.  But parallel motion was not on Active.  How can they be sure of coupling rods?  Hence "most probably".

Newton, "London Journal of Arts and Sciences" 1825.  

You will note on the first page, that Newton states the engines are not different in principle from the Hetton Colliery engines.  Faster and stronger but not different.   

Newton, on the second page, states that "The induction and eduction valves of both cylinders are worked by rods connected to eccentrics below, and the alternating power of the pistons is communicated by parallel motions and sweep rods on each side to cranks upon the spokes of the running wheels".  This implies that some locomotives had coupling [sweep] rods.  

Now what of the contemporary Active drawings.  

Our primary first hand observer was John Backhouse, a 14 year old who drew the consist, on the spot, on opening day.  He gave little thought to recording any mechanical details.  No chains.  No return cranks.  No coupling rods.  It is useless for our inquiry.  The Backhouse sketch remained out of public sight.

Earlier in this thread, I attributed this drawing to Longridge.  

According to the Science Museum, it appeared in Adamson, 1826.  The only copy of Adamson online does not include the drawing, so I forgive myself for not catching the detail.  Yet again, no chains.  No coupling rods.  No return cranks.

Dobbin was a first hand spectator.  He painted his scene decades later from, he claimed, sketches made on the spot.  He agrees with Backhouse in many details, a known non-public first hand observer.  Thus we can somewhat trust his image.  No chains.  No return cranks.  No coupling rods.

There is one more piece of indirect evidence.  The second locomotive delivered to the S&DR was not nearly as successful as Active.  Extant is a communication to Robert Stephenson and Co stating  "Resolved That Robert Stephenson & Co. be requested that in any engines they may furnish us with not to send any engines with new and experimental apparatus that such fitting up as hath been tried and approved already….".  My reading of this suggests Locomotion No.1 was of accepted practice and the second locomotive  delivered to the S&DR was experimental.  What was accepted?  Chain couplings.

So, given the widespread acceptance of the chain coupling in the prior art.  Given the time pressure by the S&DR.  Given the absence of George and Robert from the works. :::  I think Robert Stephenson and Co made Active with a chain coupling. Robert Stephenson and Co, under the direction of Longridge, fell back into form.   Not one drawing shows a coupling rod.  

Sure, later locomotives certainly had coupling rods. Newton states that they had sweep or coupling rods.  It is clear that Stephenson went back to the 1814 concept and coupled the axles via rods.  This drawing shows a Killingworth type engine with a return crank and coupling rod.  The rod is moved to the wheel, instead of underside, via a crank axle.

Active, however, remains uncertain.  I think the preponderance of evidence suggests a chain coupling .  

Probably 🙂

Bee
 

Edited September 7 by What About The Bee
Clarity

[What About The Bee]

Sweep Rods

The authors of the Locomotion paper of 2023 make much of Newton's second page.  I will quote again.

Newton "London Journal" 1825

"The induction and eduction valves of both cylinders are worked by rods connected to eccentrics below, and the alternating power of the pistons is communicated by parallel motions and sweep rods on each side to cranks upon the spokes of the running wheels". 

The implication that sweep rods are coupling rods is so strong that I accepted it without research.

Yet...

What is a sweep rod?

"Life of Richard Trevithick" has a paragraph where a pump is shown.  The flywheel is driven by a sweep rod.  The discussion is about a crank pin on the flywheel or a cranked axle driven by the sweep rod.
https://www.gutenberg.org/files/46634/46634-h/46634-h.htm
Search on page for "sweep rod".  

There are other steam driven pumping engine descriptions that use the term sweep rod.  It is always to connect the piston to rotating motion via crank axle or crank pin.

Here is a page that specifically states that a sweep rod is a connecting rod.
https://www.gracesguide.co.uk/Levant_Mine_and_Beam_Engine
Search on page for "sweep rod".

Therefore, l flatly state that the "sweep rod" is today's connecting rod.  The rod that connects the action of the piston to the wheel rotation.  Not a coupling rod, that connects wheels together 

So now we can label the sweep rods on the drawing

Can we satisfy Newton's description? 

"Power of pistons communicated by parallel motions and sweep rods on each side to cranks upon the spokes."

"Parallel motion"

As you may observe, as the piston reciprocates, the top cross beam is driven up and down.  The sweep rods are connected to crank pins on either side of the axle, those pins in phase with each other.  Thus, the TWO sweep rods remain parallel to each other throughout the piston stroke.

Why would Newton emphasize parallelism?  James Watt invented the first steam pump in 1769.  By 1825, there would have been plenty of steam pumps.  Each steam pump with a sweep rod, a singular sweep rod.  Stephenson's locomotive was fairly novel, with the Hetton engines first arriving in 1820.  Newton published in 1825.  The double sweep rod parallel motion was as unique as the locomotives.

"Sweep rods to cranks"
Well, sure, the sweep rods are connected to the cranks on the spokes of the wheels.  

Read the Newton description again and ask yourself, how is that a coupling rod.

Bee