China clay cda wagons

Halvarras · August 25, 2023

When Hornby released their National Wagon Preservation Group triple pack (R6963 - HAA, HMA & prototype CDA) it occurred to me that I could create my own 1986/7 china clay triple pack based off this - involving an older CDA wagon I already had (R6106). I also have four later weathered versions (R6648/9) so I was able to compare new with old with a view to a transplant - it was possible with a little carving and filing in out-of-sight locations (it's obvious that the canopy itself was (alas!) carried over from the earlier model, and I think the tub and cradle likewise but with detail tooling changes). I sat on the idea until the price of the triple pack dropped, then got stuck in - this was a couple of years ago.

Although there might have been a simpler way to do it - buy a 'blue' one, 353224 (R6708) and an HAA - this would probably have involved some waiting, 3 separate orders with 3 lots of P&P so would have cost more, plus unweathered blue ones were hard to find at the time; and wouldn't have saved all of the work as a different set of issues would have arisen. So here's the set:

And what I did:

A photo of HAA 351297 in St Blazey Yard appears in John Vaughan's book 'An Illustrated History of West Country China Clay Trains', which says that it was specially cleaned to test the discharge of china clay from this hopper design (I've seen reference to a different pair of HAAs involved in this trial but this is the one with photographic evidence).

The model uses the HMA wagon renumbered and relettered as these markings were 'boxed' unlike the HAA. That was the easy one!

The HAA test must have been successful because it quickly led to this. The prototype CDA 353224 uses this body on the underframe of the HAA (I made sure to get this the correct way round!) - this 'removed' the above-frame brake distributor and added the correct pattern rounded solebar gear casings. Its unique and short-lived end frame- mounted ventilators were fashioned from 10thou plasticard referring to the image published earlier in this thread, which disappeared shortly after completing the model - a close thing since this is the only photo I've ever seen of the wagon with this feature. The ladders are cut from Ratio plastic signal ladders. The canopy required painting from red to blue, and the odd grey-printed number panels changed to black with Railtec transfers and Fox white coaching stock numbers (also used on the HAA above).

And 353224 must have been successful because it led the this one and 137 others!

The CDA underframe from that one was combined with the body and cradle of the earlier model to create the first production wagon, in the condition I found it in St Blazey yard nearly 36 years ago. Some 'excavation' of the top side of the underframe was required to get the older cradle to fit, and body and cradle are fixed to the underframe via two self-tapping screws, diagonally offset because the near full-length steel bar ballast weight is located in a central 'well'. Markings were replaced with Railtec transfers.

The silver on this older body is duller than the other two, and I noticed the canopy frame was grey, so I finally found a purpose for Humbrol's currently dull No 11 silver!

Although these models were 'completed' two years ago I knew they weren't properly finished. The HAA was, but the other two required canopy winding gear (did 353224 actually have this in its original configuration or was it just a 'proof of concept'? Is that why the ladders were there?) which, after a lot of head-scratching, were fashioned from square-section rod, Hornby track pin, wire and bits of insulation) and 375000 also a brake distributor shield (scrap nameplate etch and brass wire), neighbouring air tank (plastic sprue, scrap etch and wire) and that small air vent swapping sides at this end, unique to 375000. Also gaps cut and filed into the cradle's lower framework. CDAs being a 'hot topic' I got the models out last week and sorted these features, which were very fiddly - now I remember why I stopped short of these first time around! And a good job I screwed not glued 375000's body in place.....perhaps I knew...... However I've stopped short of those drain holes, 353224's HAA buffers (which I noticed in that photo) and no doubt a few other details apparent to a 1980s wagon expert, which I am not (most of what I know I've learned on RMweb!) I hadn't even intended to model the 1980s until 29th March 2019........

This all left me with a new HAA body on the early 'pivoting' underframe for disposal at some point.

I fully understand that the Hornby model has shortcomings but I don't demand 100% fidelity so they're good enough for me. However those four other weathered CDAs, which have nostalgia value for me, will NOT be getting the canopy winding gear/shield/air tank upgrade as I value my sanity too much!

The Fatadder · August 25, 2023

I have done a lot of research into the prototype CDA. I have seen a couple of photos in its original condition, one of which is in the works the other at St Blazey. (The works photo clearly shows the good opening mechanism). The initial production series wagon was then built (with slightly different end arrangement) before standardising on the series production. At some point around this time the wagon was rebuilt with the series production end vents (rather than 375000’s non standard arrangement). There is a photo of it under test in this arrangement still with red frames. Before eventually getting a repaint into ecc blue with logos, ecc blue without logos and finally EWS.

Ive previously modelled it in original condition from a Hornby mode with a scratch built roof. More recently I’ve converted a Cavelex model in 1999 condition just before it went into EWS

Halvarras · September 6, 2023

I was out and about this afternoon, mainly because Realtimetrains was suggesting an 18-car IET was coming down the branch from Newquay! Seemed unlikely but I intercepted it at Middleway anyway - needless to say it was only half that length......

However peering over the gate at the far end of St Blazey yard it is obvious that scrapping of the long-stored CDAs has begun, two having had their hoppers lifted off and one of the underframes cut in half (as far as I could tell from a distance):

As I understand it the Bodmin & Wenford Railway will most likely take around half a dozen of these CDAs, mostly from those withdrawn last month so already in working order, along with first-built 375000, although it is acknowledged to be in poor condition. These pics were taken through the vegetation from the road:

At this end the vertical shaft of the canopy winding gear is missing - you can see the top part (gearbox presumably) beyond the large vent. Several of the stored wagons are like this. Note '000's white number panel - all others are yellow.

At the other end ('000's unique end with small vent on the wrong side) both the air brake distributor and air cylinder are missing - the pipe connections to both, and the vacant cylinder cradle, can be seen through the end framework.

Not many have had these parts removed, and I'm a little disappointed that, with so many available, 375000 was targeted as a 'Christmas Tree' parts donor. Since the first of the 13-ton 'clayhood' wagons B743000 was preserved at the Wheal Martin China Clay Museum it was not beyond expectation that the first production CDA would be similarly claimed, if not by the Museum then the BWR up the road, and efforts made to keep it intact just in case. This will make its preservation more difficult than it needed to be (in my opinion) but as I've said before there is no shortage of replacement parts in the immediate vicinity, some still in working order until last month, so hopefully it can be restored to its former glory.

There has been mention of 375001 also joining the BWR's preserved rake, this one also long out of use is stored alongside the road and appears to be intact.

Following developments with interest....!