Improving Hornby CDAs

[The Fatadder]

For my cameo challenge layout I need to put together two sets of 8 CDAs, I have a box of the early 2000s Hornby models which will be the starting point.

 

At the moment my thoughts are to tackle 3 main areas:

• The chassis: First of all is the removal of the fictional box which runs along the length of the wagon, then I somehow need to get them fitted with P4 wheels (with break disks on opposite axles).  Not that easy given the limited space, though having seen a video on youtube of Hornby HAA running on Calcutta Sidings there must be a way of doing it.
• The ends: Add the missing operating linkage to one end, my thinking here is a simple representation with a square of evergreen strip, with a hole drilled to accept a length of 0.8mm brass rod.  
• The sides: I am going to do a test example drilling out the holes in the sides / ends to see how it looks.  I have a feeling that with the over thick plastic moulding it will not look right.  Option 2 is to just add them as either a transfer or with paint 
• Finally (and most importantly) the roof:  which frankly is awful (its such a shame Hornby didn't bother tooling up a new hood at the same time as the new body / chassis).  The first plan was to recess the existing hood into the top, first cutting the vertical plate off the side, then cutting away material from the inside of the hopper by reducing the thickness so that the roof should fit.  At this point I looked again at prototype (rather than working from memory...)  The issues are much more complex, Firstly the Hornby hood is too long, I would say by almost 5mm at each end.  Secondly the hood should continue down much lower into the hopper (to just below the line of holes in the side).  Unless someone tells me that a suitable replacement part has become available from the trade in the past 7 years, my logic is to chop down the length, rebuild the ends with wire, increase the width / depth of the hood with plasticard profiled to shape and then add the flat areas filling in the ends.  

I will also be attempting to model the prototype (with end ladders and a hood which is the opposite way round) but the main difference there will just be the ladder and the movement of brake equipment to below the chassis.

 

Now I am interested to hear what others have already done to improve these wagons before I start...

[The Fatadder]

A further refinement to the plan for the roof after finding this photo https://ukrailwaypics.smugmug.com/UKRailRollingstock/C-tops-codes/CDA-china-clay-hoppers/i-R8kKNbv

 

That looks to me pole I can keep the blue part of the Hornby canopy, remove the area with the ties, as an L section circa 6mm between the under side of the hood and the under side of the side slots and then deepen the ends. Replace the raised cover along the side with brass folded to the required profile (maybe an etch if i have enough other bits to fill a sheet)

[crazynitwit]

For my cameo challenge layout I need to put together two sets of 8 CDAs, I have a box of the early 2000s Hornby models which will be the starting point.

 

At the moment my thoughts are to tackle 3 main areas:

• The chassis: First of all is the removal of the fictional box which runs along the length of the wagon, then I somehow need to get them fitted with P4 wheels (with break disks on opposite axles).  Not that easy given the limited space, though having seen a video on youtube of Hornby HAA running on Calcutta Sidings there must be a way of doing it.
• The ends: Add the missing operating linkage to one end, my thinking here is a simple representation with a square of evergreen strip, with a hole drilled to accept a length of 0.8mm brass rod.  
• The sides: I am going to do a test example drilling out the holes in the sides / ends to see how it looks.  I have a feeling that with the over thick plastic moulding it will not look right.  Option 2 is to just add them as either a transfer or with paint 
• Finally (and most importantly) the roof:  which frankly is awful (its such a shame Hornby didn't bother tooling up a new hood at the same time as the new body / chassis).  The first plan was to recess the existing hood into the top, first cutting the vertical plate off the side, then cutting away material from the inside of the hopper by reducing the thickness so that the roof should fit.  At this point I looked again at prototype (rather than working from memory...)  The issues are much more complex, Firstly the Hornby hood is too long, I would say by almost 5mm at each end.  Secondly the hood should continue down much lower into the hopper (to just below the line of holes in the side).  Unless someone tells me that a suitable replacement part has become available from the trade in the past 7 years, my logic is to chop down the length, rebuild the ends with wire, increase the width / depth of the hood with plasticard profiled to shape and then add the flat areas filling in the ends.  

I will also be attempting to model the prototype (with end ladders and a hood which is the opposite way round) but the main difference there will just be the ladder and the movement of brake equipment to below the chassis.

 

Now I am interested to hear what others have already done to improve these wagons before I start...

may i ask what cameo challenge this is and thats quite an undertaking, to upgrade all 16 wagons. 

[The Fatadder]

may i ask what cameo challenge this is and thats quite an undertaking, to upgrade all 16 wagons. 

 

My layout for the MRJ / Wild Swan Cameo Challenge Wheal Imogen - here http://www.rmweb.co.uk/community/index.php?/topic/122113-ecc-wheal-imogen-p4/?view=getnewposts

[The Fatadder]

This evening I have been working on my initial prototype wagon, (although digging through the stock box this is in fact my third attempt at improving the roof (with the previous two getting to the stage of cutting off the flat section and then stopping...)

 

First of all a request, does anyone have a 1980s / 1990s photo of a CDA roof?  All I have been able to find are pictures showing the details on an EWS liveried example, and it is from this I have made my approximations.  I would be interested to compare with the original to ensure that am as correct as possible.

 

Second a disclaimer, this is not 100% accurate!  That said it is a lot more accurate than Hornby's attempt, and about as accurate as the rest of the HAA shell that it is sitting on (so not a lot I guess...)  The aim is to take a pretty poor wagon and make it look at least tolerable within the scope of a small layout.  If I have made any glaring mistakes please point them out, Id rather know now than after I have made another 15 of them!

 

Anyway onto the build:

This was the start point, not quite straight from the box (as its previous owner has made a start marking up the slits for the weathering) 

First up the wheels,

I managed to get a set of Maygib 14.5mm coach wheels in, but it is not that free running.  I think more material needs to be removed from the backs of the W Irons and the axle holes drilling out.  A job for another day!   The rest of the chassis work has been put to one side for the moment...

 

Next up the end, 

I made a very rough approximation of the gearbox housing from a Waitrose BBQ kabab stick drilled to accept a length of 1mm rod.  This was then profiled with an angle to match that of the end of the hopper, before supergluing into position 

 

​Then onto the important bit, the roof

​​The first step was to tidy up the work bench (this was buried under a years worth of modelling & assorted other junk) before removing the original roof from the wagon. 

Next the roof was prepared, cutting off the worst elements of fiction from the Hornby tooling.  This was a simple cut to remove the silver section from the blue. 

The end was removed from the rest of the tooling at one end (it is a separate part glued on) before shortening the hood to match the prototype (if I remember rightly it was approximately 10mm).  Once cut the original end was glued back into place, before re-profiling both ends to closer match the prototype.  

 

Back to the body it was time to prepare for the new roof, I started by filing an angle onto the top of the wagon slimming down the over thick sides.  (this is very rough on one side which was done by mistake (its covered by the roof). 

Next was to fit a false floor (set to the height of the infilled areas around the top of the hopper), this was approximately 5 rivets from the top of the wagon.  a couple of brackets were glued in place followed by the plasticard floor.

 

The ends of the roof needed to be extended down to the new floor, again cut from plasticard and profiled to get as close a match as possible to the Hornby ends.  A third length was also glued along the inner edge between the two ends.  I am giving though to drawing these up to run through Silhouette Cutter and make new one piece ends)

 

Finally the roof was test fitted into position, and the cover was added along that side (a length of Evergreen strip roughly profiled to shape).

 

The model now needs filler, (a lot of it due to the gaps between the roughly cut parts to provide clearance to the various angles).  It then just needs some silver and ECC blue paint to finish it off (then to repeat for 15 more wagons.)

 

 

 

 

 

 

 

[pharrc20]

Interesting and timely thread as my uncle has just purchased 11 of these newer style Hornby wagons from our exhibition club stand today... to bolster his existing fleet of these models for his own intended Cornish layout.

Inspired to look for a top view I have only found this one from flickr in EWS days https://flic.kr/p/8R5Mxo

I will follow with interest cheers Paul

[The Fatadder]

That photo is very interesting in that the plate on the right side of the wagon is missing, giving a much clearer view of the most important area (fortunately I think the obstruction caused by the plate is perfect at hiding the missing strapping between the hood and the side of the wagon

[The Fatadder]

On to the first production batch, my plan had been to build complete locos in batches of threes but at the last minute I changed my mind to build the whole lot in two batches.

 

I have decided to start by building the whole rake for 1988, then at a later date build the whole rake for 1998. In addition I have also decided that each rake will consist of 9 wagons rather than the 8 originally planned. For some reason I think that an odd number of wagons looks better than an even number...

 

So tonight I prepared 8 more hopper shells, this time only filing on three sides. The hoods have also been prepared, although strangely these differ from the initial wagon in that both ends of the hood are part of one moulding. Clearly the previous owner of these wagons must have very carefully removed one end and reglued it. It does however add extra work to shortening the hood which now requires an extra cut. The next step will be shortening the hood, then preparing the new plasticard pieces.

 

In addition I have dismantled one wagon to separate the cradle from the hood (in this case it had previously been sprayed EWS red). This has now been given two coats of Railfreight Red (although still needs at least one more coat).

Edited October 30, 2017 by The Fatadder

[Daddyman]

Regarding re-wheeling, are you aware of this thread on the Scalefour Society pages? 

 

https://www.scalefour.org/forum/viewtopic.php?f=39&t=4737

[The Fatadder]

Regarding re-wheeling, are you aware of this thread on the Scalefour Society pages?

 

https://www.scalefour.org/forum/viewtopic.php?f=39&t=4737

Thanks for that, some interesting points

 

 

My first converted wagon uses maygibs which fit between w irons (just) but are not that free running. I need to investigate the reason and then resolve before I buy another 16 pairs of wheels. Exactoscale is another option (but the axles are awful), alternately it will be a need to file the w irons back to accept branchlines or Gibson wheels which are fractionally wider on the wheel face.

[The Fatadder]

Over my morning coffee I have been completing some rom calculations as to the number of CDAs needed for the layout. My testing has 3 Clay Tigers fitting within the works, based upon lengths in the Kernow tiger thread it appears that the equivalent is 5.5 CDAs, this clearly needs to be checked on the templot print this evening but if true I need a lot more CDAs (if I shorten to 5 that’s just one extra to be batch) while selling off the ten spares will fund the wheels.

 

Anyone know if Keen Maygib coach wheels are still available? I’m struggling to find a source

[timbowilts]

AFAIK Keen Maygib are long defunct.

These days I purchase my coach and wagon wheel requirements form Wizard Models because

a) it takes too long to get anything out of Markits (I've had an unfulfilled order with him since October 1st but that's early days yet by all accounts)

b) Alan Gibson doesn't do e-commerce ad I like being to oreder from a website

 

Regarfds

 

Tim T

[The Fatadder]

AFAIK Keen Maygib are long defunct.

These days I purchase my coach and wagon wheel requirements form Wizard Models because

a) it takes too long to get anything out of Markits (I've had an unfulfilled order with him since October 1st but that's early days yet by all accounts)

b) Alan Gibson doesn't do e-commerce ad I like being to oreder from a website

 

Regarfds

 

Tim T

Guess it’s into eBay then, it’s been a while since I last purchased wheels (8 years or so at least) but the benefit of maygibs was a solid wheel and a a tire profile which is narrower than Gibson / Ultrascale/Branchlines yet more generous than Exactoscale

 

It will also cause complexity in the last two 37s which are still awaiting rewheeling, as my standard fix to deal with the poor design of Bachmann’s co co bogie was to use maygibs on outer axles and the branchlines wheel on the middle. The 0.25mm difference in radius eliminates any wobble on the centre axle. Time to go through stock that’s earmarked for sale / display and liberate the maygibs!

[Daddyman]

AFAIK Keen Maygib are long defunct.

These days I purchase my coach and wagon wheel requirements form Wizard Models because

a) it takes too long to get anything out of Markits (I've had an unfulfilled order with him since October 1st but that's early days yet by all accounts)

b) Alan Gibson doesn't do e-commerce ad I like being to oreder from a website

 

Regarfds

 

Tim T

Peter's Spares have some Markits bits and everything comes the next day. 

 

Not sure whose wheels Wizard's are, but they also come next day. 

[The Fatadder]

Rebuilding the hoods is taking a lot longer than I hoped, but I have now finished the first batch of 5 hoods. Making the first cut approximately 2 mm from the end with the small peg. Measuring the thickness of the end and then a second cut to chop out the excess material.

 

Once checked with an engineers square to ensure the two parts were square the hoods were reassembled and are now ready to start work on the plasticard sub structure. (Although the decision to make now is whether to get on with building the interesting bits, or to spend another night building the next 6 hoods.)

 

After another coat of rail red the frame for the prototype wagon is nearly ready for reassembling.

 

Still looking for a wheel source, annoyingly Colin Craig’s website lists all of his other wheels bar the 14mm one that I need ( presumably having ran out of maygibs). Will be dropping him an email today to double check

Edited November 1, 2017 by The Fatadder

[The Fatadder]

The 1980s batch have now been fitted with the brackets to support the false floor. I then moved on to the final prep work before new construction starts, modifying one wagon to its original condition.

 

If I was starting again I would use a HAA as a doner, as I don’t have one I have used a CDA. The cradle frame is now in Rail red, however modification was still needed to the ends. First the vents were removed, this left a large hole which had to be filled. Next the ECC loco has to come off, I started applying IPA then scraping off. Unfortunately it took the silver off as well so was repainted with Humbrol metallic silver. Once weathered it will blend in perfectly. The final job was to add the in fill area on the end brackets. This was formed from 20thou plastic cut to shape and glued into position (it now just needs Rail grey paint).

 

Still on track to have batch 1 finished this week

[The Fatadder]

The prototype wagon is now nearing completion, first the 5 1980s wagons were fitted with their false floors. Next the lower end plates were cut (each needing minor adjustments to get a bespoke fit with minor variations in floor height) as a result I only got one installed on a hood

 

With the hood finished it was out with the filler to prepare the ends, at this point I realised I had made a mistake on the original test build (and replicated it on all the others) building them all back to front! In the end I have been rotating the bodies on the chassis as I build.

 

With the body finished and reassembled I added the ladders and roof mechanism to the prototype wagon along with fitting (and painting) the protective plate along the side. I’m still unsure about this, it just looks a bit too chunky

 

 

Finally I test fitted the roof (after filling and repainting the joint from shortening the roof.) I also added dark ECC blue highlights on the roof in preparation for weathering

 

 

Edited November 2, 2017 by The Fatadder

[The Fatadder]

Note: remember that CDAs are not symmetrical, I was working with the body off chassis on the first few, I then fitted the roofvthe wrong waybroubd (so end vents were on the wrong side.). Now fixed.

 

Two more are built, and the first 4 are now p4 after minor filing and fitting exactoscale wheels. Hopefully the final 2 will be converted tomorrow, then time to fit couplings and add some extra weight. I’m planning to start breaking up Blackcombe to recover point components and a few other bits, so will try and use trdvtrsck that sill works for a quick test...

Edited November 5, 2017 by The Fatadder

[The Fatadder]

After finishing off the Polybulk conversion to P4, I have got on with more work on the CDAs.

 

The first job was to build the final two hoods for the 1980s batch, which are now awaiting the final filler coat. 

 

They were next fitted with Exactoscale P4 wheels.

 

All that remains is silver paint, weathering and fitting instanters, then I need to do it all again for the 1990s batch...

Edited November 6, 2017 by The Fatadder

[The Fatadder]

Today I fitted the remaining linkages to the hoods, along with adding the hood mechanisms to the ends. The latter were soldered up using a rough jig filed into an off cut of hardboard.

With this complete the hoods were glued into place, so the wagons now just need Instanters fittings (which should be in the post) while 3 need renumbering. At which point they will be ready for a lot of white paint when weathering

 

 

Hopefully how they should look arriving into Wheal Imogen

 

Before / After (although the Before has been fitted with Exactoscale wheels)

 

Edited November 8, 2017 by The Fatadder

[Mick Bonwick]

 

CB80EC15-ADA5-4BFD-B775-E11369A0D729.jpeg

Hopefully how they should look arriving into Wheal Imogen

 

 

Nice bit of scenic work! :-D

[The Fatadder]

Nice bit of scenic work! :-D

I think I need to add some track and a backscene and make it a proper photo backdrops

[JDW]

Nice work, they look much better than out of the box.  I'm curious about the (Railfreight?) red one though, I thought they were all blue until EWS maroon?

[The Fatadder]

Nice work, they look much better than out of the box.  I'm curious about the (Railfreight?) red one though, I thought they were all blue until EWS maroon?

 

It is the one off prototype CDA (hence it does not have the end vents, the air distributer is below the chassis and there is a triangular grey box between the support legs at the ends along with a ladder.  The roof also opens to the opposite side of the wagon to the ECC wagons.

 

I am less clear as to the colour of the roof (hence have just gone with ECC blue)  I have a feeling that it will probably turn out to be rail grey and I will need to repaint it...

 

There is a thread somewhere else on the forum with a photo of the real thing 

http://www.rmweb.co.uk/community/index.php?/topic/45043-china-clay-cda-wagons/#entry495794 

[JDW]

It is the one off prototype CDA (hence it does not have the end vents, the air distributer is below the chassis and there is a triangular grey box between the support legs at the ends along with a ladder.  The roof also opens to the opposite side of the wagon to the ECC wagons.

 

I am less clear as to the colour of the roof (hence have just gone with ECC blue)  I have a feeling that it will probably turn out to be rail grey and I will need to repaint it...

 

There is a thread somewhere else on the forum with a photo of the real thing 

http://www.rmweb.co.uk/community/index.php?/topic/45043-china-clay-cda-wagons/#entry495794 

 

Thank you for taking the time to answer my rather foolish question with good humour and politeness, I realised just now that I'd somehow skipped over posts #16 and #17, which would have given me the answer...!     I shall hang my head in shame