GWR ex-Cambrian Railways 73-class 0-6-0

[RosiesBoss]

Introduction

 

As noted in Post #3 in http://www.rmweb.co.uk/community/index.php?/topic/70550-carmarthen-junction-miscellena/, I have had mixed success in using Mainline/Hornby Dean Goods models. In addition to the models listed in that post, I had another Mainline example (purchased cheaply as a non-runner) that I could not ever get to run well. It seems that the tender drive unit was just too worn, so it sat on a shelf awaiting a new use.

Issues 85 and 86 of “Great Western Railway Journal” provided many images of ex-Cambrian Railways 0-6-0s. Russell provided outline drawings (especially Fig.161) and RCTS provided more details of their histories. The closest match I could find for locos that ran in my selected modelling area (Mid-Wales, 1930s) was the rebuilt 73-class. These had been provided with Dean Goods boilers and fittings, so my model could use the Mainline model as a starting point.

 

 

Prototype Notes

The 73-class (or Cambrian Railways “Large Goods”) locos were built in several batches by both Vulcan Foundry and Neilson Reid & Co. between 1894 and 1899. They were typical British inside-cylindered 0-6-0s and all came into service with the GWR from 1922. They remained working over the former Cambrian system until their eventual withdrawal, between 1926 and 1947. All except one were fitted with Dean Goods boilers. All of their tenders (and those of the later 15-class) were enlarged by means of the insertion of a steel strip to raise their heights (and water capacity). (See Green, p.20.) This modification can be seen in some photos, such as that of 896 on page 257 of GWJ 85. The weight diagrams in Russell do not show the resulting height of the tenders. Photographs of the locos in GWR service display tenders that, at first glance, look like ROD tenders, as they have similar proportions. However, their wheelbase is significantly shorter. The wheelbase of the 73-class locos is also different from that of the Dean Goods, but is very similar to that of a small 4-6-0, such as a Manor Class.

 

Donor Models

• Boiler and footplate: Mainline Dean Goods
• Loco chassis: cut-down whitemetal 4-6-0 chassis block bought at a sale at “Train Trader”, Pymble, NSW. This had been designed to take an X04 motor, driving on the rear axle.
• Tender chassis: Tri-ang B12
• Tender body: cut-down Bachmann ROD

Construction

I began by removing the loco superstructure from its chassis and tender, which were stored in my scrapbox.

 

I then moved to the cast chassis, where I cut off the front extension (over the 4-6-0’s bogie). I trimmed the chassis and the body so that both fitted together, with the central axle lined up under the centre wheel splashers. I fitted 20mm dia Romford wheels to the chassis and then checked whether the rolling chassis would fit under the body. I fitted Romford crankpins to the wheels and fabricated connecting rods from modellers’ brass strips.

 

I made up a motor-gearbox assembly from a SE Finecast motor mount, a small motor similar to Hornby Type 7 and a set of Romford 40:1 gears. (I have found such motors suitable for locos pulling light to moderate loads.) This assembly was installed to drive the centre axle, not the rear axle as originally set up on the whitemetal chassis. The pickup plate was then modified to suit.  It now looked like a workable assembly:

 

 

Internal portions of the wheel splashers were then trimmed away until the wheels turned freely. The body-to-chassis mounting points were then adjusted so that the buffers were at the correct height. The ballast weight was removed from the boiler and trimmed back to make room for the motor.

 

Sitting on its new chassis, the loco now looked like this:

 

Clearly, the cab, sandboxes and wheel splashers needed to be changed, so I removed the following from the body:

• Cab
• Sandboxes

The rear of the model now looked like this:

 

I fabricated a new cab from copper sheet and fitted it with the backhead/ floor assembly recovered from the original cab and test fitted to the body:

 

The cab was then attached with 5-minute epoxy. The backhead/floor was further trimmed, then attached with cyanoacrylate cement. Gaps between sidesheets and wheel splashers were filled with automotive filler, allowed to dry and then trimmed back.

 

The next step was to fabricate new front and rear wheel splashers from thin brass sheet. I chose to make the front sandboxes conform to the original small design. (One batch, made by Vulcan Foundry, had larger sandboxes.) These were then test fitted, adjusted and then attached with 5-minute epoxy. Once this had completely cured, excess adhesive was trimmed back from joins.

 

 

I now turned my attention to the tender. The Tri-ang B12 tender frame has the correct wheelbase. While frame details are a little different to the Cambrian Railways, I still chose to accept them as they were. The only details I found necessary to modify were to replace the original wheels with 14mm dia ones (to adjust the buffer height), to trim back the body locating ribs and to fit a Bachmann tension-lock coupling.

 

I removed the lamp brackets, fallplate and rear handrails from the Bachmann tender body. The prototype body looks like an ROD tender – but it isn’t! I had to lower it by about 3mm and remove about 5mm from the middle so as to make it fit the frame. I found no drawings of the enlarged tenders, but photos of both 73-and 15-class locos indicate that the bottom of the flare near the top of the tender bodywork is in line with the boiler- and cabside-handrails. The two body halves were then re-joined with 5-min epoxy and then finished with automotive body filler.

 

 

I made up a simple loco-tender coupling from brass and an 8BA bolt, then fitted the cab roof. The lever reversing rod was replaced with one more appropriate for the CR’s standard screw reverse. I attached the tender body to its frame with contact cement and reviewed its appearance before adding further details.

 

It was clear that the gap between tender and loco was too obvious, so I fitted the ROD tender’s fallplate. I then fitted new handrails to tender and cabside, as well as new GWR-style lamp brackets, bent from office staple wire.

 

 

The model was now ready for painting, starting with grey spray primer for the bodies.

 

 

Whistles, recycled from the donor Dean Goods, crew and front scale coupling were fitted after painting with Humbrol enamels.

 

I chose to number the model as 885 – one of the last survivors and which was allocated to Llanidloes and Brecon sheds on the Mid-Wales line in the 1930s. I could not find anyone selling suitable etched plates, so I printed them. If suitable etched ones become available, I will consider replacing the home-made ones. Coal was added after all paint, lettering and varnish had fully cured.

 

 

My wife has observed that the model “looks too shiny”. However, there are photos of ex-works locos in similar condition on page 253 of GWRJ No. 85. In my alternate version of reality, there are enough cleaners in Carmarthen Junction Loco Depot to keep them that way!

 

Reflection

This has been another enjoyable “scrapyard challenge”, making good use of many bits and pieces picked up cheaply at “bring and buy” stalls and the like – even the Romford wheels, axles and gears. I don’t pretend it’s perfect – far from it! But I do think I’ve captured the essence of the real thing and I now have another loco suitable for my Mid-Wales area layout. I believe the total cost was well under A$50. No other RTR GWR 0-6-0 is currently available in Oz, but the nearest generally similar model is the Bachmann J11 which retails here at around A$162. I think I’ve achieved good value for money with my simple project.

 

This little loco provides an interesting contrast with the standard GWR locos, such as the Dean Goods. The model is a worthy addition to my existing collection of “absorbed engines”: http://www.rmweb.co.uk/community/index.php?/topic/70468-gwr-absorbed-locos-on-carmarthen-junction/ plus http://www.rmweb.co.uk/community/index.php?/topic/72460-gwr-1331-ex-whitland-cardigan-0-6-0st-project/

It is another suitable example to illustrate the point that “not all GWR engines look the same”.

 

References

1. John Copsey (ed.): Great Western Railway Journal: Issues 85 and 86 (Wild Swan, 2013)
2. RCTS “The Locomotives of the Great Western Railway – Part 10 – Absorbed Engines1922-1947 (RCTS, 1966)
3. J.H.Russell: “A Pictorial Record of Great Western Absorbed Engines” (OPC, 1978)
4. C.C.Green: “Cambrian Railways Album – 2” (Ian Allan, 1981)

[knobhead]

Very nice!

 

Yet another, inspiring, thread of yours that I have saved for future reference!

 

Regards,

 

Stefan

[Mikkel]

I very much agree with Stefan. Today I've been reading through all your threads, and there is so much inspiration that I need to lie down and relax a little :-) Thanks for sharing it all.

[Weaselfish]

That's really good. Nearly all of the steam classes that operated on the old Cambrian system after World War II are available ready to run now and this is a great way of filling one of the last gaps and getting something a bit different too. Can I ask where you got the ROD tenders from please? I need one for an Aberdare and another for when I have a go at this conversion myself. 

[RosiesBoss]

G'day, Weaselfish,

 

ROD tenders seem to be very thin on the ground unless you buy them with their matching 2-8-0 loco. Suitable models would include the K's or Bachmann LNER O4 or Hornby's LNER O1 (a rebuilt ROD). I keep my eyes open at "bring and buy" stalls at model railway shows around Sydney. I did manage to find a K's one in rough condition to run with a scratchbuilt 2251 class. Rebuilt and restored, it looks quite ok. In the case of the 73-class, I had been looking for suitable "bits" for a long time, until I spotted a body (no frame) for a Bachmann ROD at the Epping Model Railway Club show about 3 years ago. I was intrigued to see a bodyshell for the corresponding loco for sale nearby. I will continue to look for more ROD tenders, so I can have a go at building one of the Cambrian's elegant 4-4-0s.

 

Regards,

 

Rob

[Weaselfish]

Thanks Rob. I'd trawled the internet looking for ROD tenders and drawn a blank so it's time to hit a few more exhibitions with second-hand stalls. I don't think we'll  be in competition with each other given our respective UK and Australian locations. Good luck with your hunt - I've never seen a Cambrian 4-4-0 modelled and I bet your pics will be great.

 

All the best,

 

Mark

[Quarryscapes]

Not a bad representation that. I've so far put together the boiler and it's fittings for my Aston Goods. Very slowly getting round to the rest of it! 

[ChrisN]

This looks great, and an inspiration as I need to build Cambrian locos of an earlier period.  I will look out for other things you do.

[Gilwell Park]

RosiesBoss

 

Hi.  Was that the Epping, Essex, England or the Epping, Sydney, Australia exhibition?  Just out of curiosity.

 

Roger

[RosiesBoss]

G'day, Roger,

 

I regularly attend the Epping (Sydney) model railway show. It has one of the best organised and largest "bring and buy" stalls of any of the Sydney shows. Over the last few years, it has been held in the Thornleigh Brick pit sports complex, utilising an expanse of indoor basketball courts. The "bring and buy" area has been an area similar in size to a small community hall, cordoned off from the rest of the show, with tables arranged down both sides and through its centre. There is usually a queue of a couple of hundred hopefuls that has gathered before opening time on the first day. Unlike most other shows, this sale area uses both cash and credit cards. It is always an occasion not to be missed.

 

Here's a link to the club's exhibition page: http://www.eppingmodelrailway.org.au/exhibition.html

 

Regards,

 

Rob

[ChrisN]

I can tell I am getting old when I read a thread and think 'Wow!' and then find I have already commented on it and have forgotten it.

 

How close is the wheelbase you have used to the original prototype?

[RosiesBoss]

G'day, Chris,

 

As implied in my original text, the wheelbase of the chassis I used is 7'0"+7'9" - the same as many GWR 4-6-0s. The actual wheelbase of the Cam Rlys 73 class was 7'5"+7'10".

 

I'm not sure if this will be of use to other kitbashers, but I have been compiling a list of models that are already in my collection or are under consideration for construction. The file includes a partial list of commercial model chassis dimensions for comparison.

Model wheelbases.pdf

 

I'm currently completing an old 1076 class double-framed pannier tank, using some body bits from a Hornby 2721 and a modified Wills Finecast 1854 class (inner) chassis. The data in the appended table was part of the research into this model. I aim to publish an account of the model's construction soon in these pages.

 

Regards,

 

Rob

[ChrisN]

Rob,

Thank you, this list is really useful.  I have from time to time tried to do the same and do have some dimensions but have found sources to be elusive.

[DCB]

The wheelbase pdf is really useful but where is the Bachmann / Mainline 2251/ 57XX Chassis?.  Personally I find the availability of coupling rods the limiting factor for chassis as I cannot make them,  The cast Triang/Hornby and H/D Wrenn chassis can be drilled to change the wheelbase to a certain extent...

[RosiesBoss]

G'day, all,

 

As I mentioned in Post #12, I'm still working on my wheelbase database. There are several more entries to add - not just the Bachmann 57XX. I published it "as is" in reply to Chris.

 

I agree that availability of coupling rods can be an issue. I have successfully made some of my own, but will use suitable commercial ones if (locally) available here in Oz. These do save some time, but still need to be "fettled" somewhat to ensure smooth operation. On my Keyser 2-8-0s, I had to replace their one-piece connecting rods with home-made jointed ones to facilitate their negotiation of 2ft radius curves. I think that 2818 still looks ok.

 

 

Regards,

 

Rob