Hackworth’s Royal George

[Half centreParticipant @halfcentre]

I have long been interested in pre-Victorian locomotives so my next project will be a 3 ½ inch scale live steam “Royal George”. This was Timothy Hackworth’s loco of 1827; a significant machine in the early development of steam traction. However as I am sure you can imagine being such an early engine design sources and records are scarce and open to interpretation. I am trying to initially produce a set of working drawings and am hoping that forum members would be kind enough to give me the benefit of their opinions and expertise on some of the more puzzling aspects arising from the surviving documents. I hope to build it as close as is reasonably possible and feasible to the locomotive Hackworth initially designed and built.

I have T R Pearce’s excellent book on the locomotives of the Stockton and Darlington Railway. This contains the earliest surviving sketch of the loco and Alan Priors conjectural drawing. Unfortunately neither is on the net so unless you have the book are not readily available!

However 2 of the main surviving illustrations are available here

Source 1 and here Source 2

In addition Hackworth’s “Sans Pereil” (1829 0f Rainhill fame) survives as a ‘hulk’ at Shildon and also as a full scale working replica. It might perhaps help to throw light on some features of Royal George built only a couple of years earlier. The net has numerous sites in which this engine is mentioned – for example – ans_Pareil_Replica_05-09-17_69.jpeg”>Source 3

or simply type Sans Pereil into an image search – Source 4

Perhaps some of you have actually seen it in real life.

Finally Hackworth built a small model of the loco

photos here – Source 4

After all that (!) here is my first ‘problem’ –

The pistons do not appear to have the conventional piston rod guides/slides/crossheads. The drawings show an inverted V under the cylinders. Sans Pereil has a more conventional arrangement, and it is hard to imagine that the Royal George relied solely on support from the stuffing box/gland to maintain the piston rods parallel motion to the cylinders. Source 2 shows the V with no apparent linkage at its base; source 1 appears to show some kind of connection?

Is it a bracket with a brass bush set into the bottom of the V to allow supported vertical movement of the piston rod or is part of the linkage mechanism as well? Or am I missing the point completely?

Your opinions would be very welcome

Many thanks

Martin

[Half centreParticipant @halfcentre]

Much needed opinions!

[WearyParticipant @weary]

Hi Martin,

Must make it clear that I know nothing about that kind of locomotive. However…… the 'motion' looks suspiciously like 'grasshopper' motion as used on stationary engines of the period.

If that is the case then the 'inverted V' is there only to carry the link which runs to the middle of the main beam. It certainly looks that way in your links above. The layout can be most clearly seen in the contemporary model. If you google grasshopper motion you will find explanations of the geometry and functioning. In this kind of motion the cylinder gland is indeed crucial in guiding the piston rod.

If it is grasshopper motion then the pump(?) rod in source 1 would need a joint of some kind put in it to allow the thing to work correctly as the main beam must be able to move in a horizontal plane as well as a vertical one.

Just an initial thought from a position of ignorance, but might help…

Regards,

Phil

[KWILParticipant @kwil]

If you look at the linkage arrangement I think you will find it somewhat like a watts parallel motion albeit upside down. A similar arrange exists in Locomotion ( the other way up!) at the top of an unsupported (from your eyes point of view) piston rod!!

PM me if you wish

[KWILParticipant @kwil]

For those who are not aware of Timothy Hackworth's Royal George. Drivers are 4ft diameter.

[Ian S CParticipant @iansc]

I have a photo of Hackworth's model ina book I have "The Pictorial Encyclopedia of Railways", by Hamilton Ellis AI Loco E, FRSA. Martin you possibly have this photo, it is a veiw with the chimney at the right hand end, as in Kwil's drawing, it has some changes from the drawing, including a different chimney, different wheels. This model is described as a laborirtoy motor, and not an exact miniature of the fullsize locomotive. Ian S C

[Half centreParticipant @halfcentre]

Thank you all for your replies – it goes to show the value of asking for other opinions – I very much doubt I would have thought of looking at it in those ways. This weekend I will ponder on what you have said – I tend to be a bit brain dead after work during the week!

Ian – the photo sounds similar to the ones on the web, it is interesting that Hackworth felt the need to make a model, I assume he did it as a prototype? It perhaps shows how close to edge of known design and technology he was operating at. He felt the need to try it out first despite the difficulties he would have known (and we as modellers know all to well !) of scaling from what works on one scale to what works on a totally different one.

thanks again

Martin

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