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RichL
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Now that my 21mm/12mm gauge test track is finished I really need to get some stock built. It is a kind of catch 22 situation though. Whilst I pore over countless books getting a hold on the exact nature of my new layout, I have no precise idea of what stock I shall need. Some stock needs building though, if only to build up experience and fill in time before the layout is ready to be built.

Firstly, there are a few Dundas Models Irish NG wagons on the go. I needed to get these running to test the test track. I hit a problem with excessive side play on the wheelsets though. Either the axles are shorter, or the bearings are different to those that the chassis were designed for. I have paused on these whilst I work on a solution. I guess that squeezing the bearings in a little should work. I also have a couple of ideas for quick and easy motive power. More about this another time.

For 21mm gauge, I have a few wagon kits to put together and an out-of-period diesel to convert to the correct gauge. I am really itching to do a steam loco though. Whilst browsing through my ever growing collection of books, I came across a drawing and photo of a tiny loco for the Newry, Warrenpoint and Rostrevor Railway on page 67 of Locomotives of the GNRI. At around 3" long, it is really tiny in 4mm scale. It is so weird that I really fancy a model. Crazy, but true.

So, I have decided to evaluate it to see if I really can model her. It was too hot to do anything energetic this afternoon so I decided to take a deep look at the design. The photograph in the book is very poor ( it was taken in 1885 or thereabouts, so fair enough). The drawing was probably made from the photo. Comparing the two, it seems to me that the drawing is not quite right. Perspective problems on steam locos make accurate scaling from a photo a real challenge, even when you know key dimensions.  I scanned the images and started playing around in Photoshop. Firstly, here is the image in the book enhanced a bit to bring out more detail.

Grendon-Victoria-orig-enh1.jpg.54962ac4a73154d6dd6a434d38b16736.jpg

This shows a few details not in the drawing, like the name of the loco seems to be on a small rectangular projection from the side of the loco, for example. The brakes appear to be only on one side of the loco. The rear bunker appears to be very rounded with pointy ends on the rear buffer beam.

Using perspective and scale corrections I then stretched the photo to get a reasonably accurate idea of the proportions of the loco

Grendon-Victoria-correction.thumb.jpg.a16d77ebc2b2b6ab7d3f329b21147f61.jpg

Because the loco photo is taken at around 45 degrees and from near ground level it is impossible to get a true side and end elevation from the photo directly. You can work out the relative proportions though by doing several different perspective corrections independently.

The main conclusion so far is that the front end has been drawn too short. Here is the original with a very rough correction below just to give you the idea.

Grendon-Victoria-side1.jpg.eafd649beafbfe3c5e49066d779a695c.jpg.

Whether I pluck up the courage to build it or not is a matter for another day, but I am finding the loco thoroughly addictive to study. My next step is to work out more of the relative dimensions more accurately and then maybe build a mock up in card to compare with the photo.

The only useful dimension quoted in the book is the driving wheel diameter at 4ft. It was built by Grendon in 1850. Not likely to be any more information to go on. Even the frame details in the drawing are probably conjectural, I guess, as you can't make much out in the photo. Looking at contemporary designs may give me a few pointers to fill in the gaps.

By coincidence I already have wheels suitable for her. I would be happy just to see it move under its own propulsion. Being able to haul something would be a bonus.

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Brazil Locomotiva nº 1 - Baronesa

Locomotiva a vapor 2-2-2 Baronesa vista de perfil

This may help with some proportions for the drawing, it's a William Fairbairn design which I suspect 'Victoria' may be based on, also the Grendon works had a connection in supplying a 2-2-2 loco to the London company working in Brazil??

There is a few dimensions here;- http://vfco.brazilia.jor.br/locomotivas/vapor-EFCB-Estrada-de-Ferro-Central-do-Brasil/pagina-01-locomotiva-Fairbairn-Sons-2-2-2-Baronesa-01-Maua.shtml

Eoin

 

Edited by murrayec
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Many thanks everyone for your help and enthusiasm!

Fairbairns are great if you are modelling the Waterford & Tramore, but 'Victoria' has all the hallmarks of being designed by someone who didn't really know what steam locos were supposed to look like ;) It is very unusual in a number of ways. Of course, some of the oddities might date from when she was running on the NW&R, but we shall probably never know. The GNRI book suggests she was originally built for an exhibition in Dublin in 1850 and later bought by Dargan to run on the NW&R, which he operated under contract for a while. The spacing of the wheels, with the front axle so far forward almost suggests that it was originally planned as a 2-2-0T

I think there was an article on Grendon locomotives some time in the 1970s or 1980s in the IRRS Journal which might give a few more details. Otherwise, I suspect the photo is all I really will ever have to work from.

The only other actual Grendon loco I have seen a drawing of is on p29 of the same GNRI loco book. This is an 0-4-2 tender loco of 1849. The book suggests it is a conjectural drawing and it shows little detail. Incidentally, there are some other really tasty locos in that book, including a couple of 2-2-0 tanks - maybe for another time!

No point in getting too obsessed though - if the consensus is that you all want me to have a go, then I shall have to go with what we have. I do have quite a few drawings of other locos of the period, so feel sure I can cobble something convincing together in due course ;)

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I managed to find the actual catalogue for the 1850 Dublin Exhibition online https://digitalarchive.rds.ie/files/show/2630   How cool is that?

It even contains a brief description of the locomotive........

Machines for raising and moving Bodies ; Steam Engines, Carriages, Ships, Boats, Etc.

Your Committee next advert to the large cast iron trying table, the locomotive engine, and the stationary steam engines, exhibited by Messrs. Grendon of Drogheda, the working of which latter engine added so much to the interest of the Exhibition, by its being used as the power for moving several irnportant machines exhibited by manufacturers. 

Their locomotive engine exhibited deserves notice as one of a new class of light passenger engines made by them for the Newry and Warrenpoint Railway, on which it is reported to have worked most satisfactorily. The cylinders of this engine have a diameter of nine inches, with a twelve-inch stroke, and the steam-valves are wrought with the new patent variable expansive link motion. The diameter of the driving wheels is four feet, that of the trailing wheels, two feet ten inches, and the engine is so constructed as to carry sufficient coke and water for a journey of twenty-five miles, at a speed of forty miles per hour. The advantages which it possesses over the engines in general use, as stated by the Messrs. Grendon, are, its not consuming more than one-third of the ordinary quantity of coke, and from its lightness causing much less injury to the permanent way. 

As the Messrs. Grendon are the first manufacturers, in this country, who have constructed locomotive engines for sale, several of which are at present in use on the Drogheda and other railways, and which are reported by the engineers to have worked effectively for a considerable period, your Committee deem it but just to these spirited and successful manufacturers, to award the Gold Medal, value £5, as expressive of their approbation of these exertions.

......Not a lot more information, but clearly originally built for coke rather than coal - and the diameter of the non-driving wheels is stated, which I did not know. Unfortunately, the wheels I have are 12mm - a scale 2" too big, but don't tell anyone. They will wear down in time. ;)

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Sounds like a ground breaking project, Mike Sharman funnily enough published an article on designing a loco from a few know dimensions and a photo.

An interesting what if would be to include a section of 6'2" gauge to your layout based on the premise that the Ulster Railway did not re-gauge in 1848 🙂

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4 hours ago, Mayner said:

An interesting what if would be to include a section of 6'2" gauge to your layout based on the premise that the Ulster Railway did not re-gauge in 1848 🙂

That would make the diamond crossing on my test track interesting! Why not throw in 4ft 8 1/2 as well, since the Dublin & Kingstown might equally not have regauged. One railway (forget which) went for 5ft 2in, which would be impossible on shared track, as would that zero gauge one out West. ;)

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OK, a brave stab at redrawing the drawing, based on 'correcting' the perspectives on the photo. The main difference is that the loco seems a bit longer at the back and the front wheels are slightly further forward. I think it makes a slightly more elegant loco. Very difficult to be sure though about the dimensions. Next will be a rough 3D mock up so I can compare the changes with the photo. I can better judge the height, diameter and position of the chimney, dome etc from that too. My rear buffer beam is too low, but easily corrected. CAD software might be a better way of doing this, but I don't want to have to learn new software just for one loco.

Original at the top, my own rough draft effort below it...

 

Victoria-005.thumb.jpg.7d23ef5c7a3162f5115574f2bff08f59.jpg

I found a photo of an original Grendon loco in 'The Midlland Great Western Railway of Ireland' by Ernie Shepherd, p28. That is a 2-4-0 tender loco built 7 years or so after 'Victoria', but should be handy for some of the smaller details

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1 hour ago, David Holman said:

The latest RM has a full review of the new Hornby 'Rocket' set. Somehow, they have fitted a motor gear box into the tiny body, with enough traction to haul three coaches.

Yes, remarkable. Bachmann's OO9 Baldwin is another example of a fine, but very compact loco in 4mm scale.

'Victoria' is made easier by the tanks along the full length of the boiler which should hide the mechanism. Small motor technology has come on leaps and bounds in the last few years. I should be fine!

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13 hours ago, RichL said:

OK, a brave stab at redrawing the drawing, based on 'correcting' the perspectives on the photo. The main difference is that the loco seems a bit longer at the back and the front wheels are slightly further forward. I think it makes a slightly more elegant loco. Very difficult to be sure though about the dimensions. Next will be a rough 3D mock up so I can compare the changes with the photo. I can better judge the height, diameter and position of the chimney, dome etc from that too. My rear buffer beam is too low, but easily corrected. CAD software might be a better way of doing this, but I don't want to have to learn new software just for one loco.

Original at the top, my own rough draft effort below it...

 

Victoria-005.thumb.jpg.7d23ef5c7a3162f5115574f2bff08f59.jpg

I

Strange little Beastie! difficult to build a plausible looking model from the photo.

The original sketch appears to be the most likely of the two though the leading axle looks like it would barely clear the rear of the cylinders.

I would be inclined to sketch out the cylinders and ashpan, the fit the axles to suit.

226887500_Victoria2-2-2.jpg.8fcfb4f3134c6079dfac6d5aee8a9004.jpg

The L&M Planet drawing is a good example of early inside cylinder loco practice

https://simple.wikipedia.org/wiki/Steam_locomotive#/media/File:Stephenson_110_Planet,_1832.jpg

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Sorry for the long delay in responding but I have been away for a few days and didn't have access to my notes. You raise a very good point, Mayner! I was mainly going on the photo and drawings of other locos of the same period. The steam chest was full width between the frames in all drawings I looked at. Translating that to the photo , the front of the far front wheel would have to project slightly beyond the front of the steam chest to appear thus in the photo....

Grendon-Victoria-orig-enh1.jpg

On reflection, the steam chest, or at least the lower part of it, is quite narrow. You can see this from the faint outline of the cylinder covers on the front of the steam chest. Having said that, the cylinders were quite short, possibly only 13" stroke (though one source suggests 15"). That's well below the diameter of the wheel at 34". As you rightly suggest though, the steam chest couldn't go over the top of the leading axle - unless it was sloped sharply upwards towards the rear. Not impossible, as some strange angles were used at this period it seems, but perhaps unlikely.

When I get the chance I shall take closer look at the front end and try to reconcile the problems.

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I've managed a revised drawing taking account of the steam chest and also the firebox. The main difference from the original drawing now is that mine is still stretched a bit towards the rear

 

Victoria-005-mk2.jpg.4f1018ed53fc7b45a68bd0f47df0ea49.jpg

I think only a mock-up is going to improve things from here - something in 3D to compare directly with the photo.

Here's another excellent prototype - original Cork Blackrock & Passage Rly from before the line was converted to narrow gauge - very tempting too, but not for now!

98195547_2891388294291418_83215704238671

Edited by RichL
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