Changing horses in mid-stream

I bought this tank wagon kit some years back at Guildex. It was sold with rubdown transfers for the “Basic Slag & Phosphates Companies” and was for the conveyance of sulphuric acid. The picture on the box is for a different firm entirely as the kit was then new and the box art work was not yet ready. The prototype wagon was based in my home town of Newport, Monmouthshire, hence my interest in it. In the tardy fashion typical of many of us modellers, I’ve just got round to it. This is a mixed media kit. The tank and frames are moulded in ‘milky bar’ resin, there are some white metal castings, plastic buffer housings, turned steel buffer heads and etched brass running gear. It requires a set of split-spoke wheels; I chose Slater’s.

I was informed that the wagon dates from 1933, and is a Charles Roberts product. Its style is however somewhat earlier, with wooden solebars more typical of the twenties; by 1933 most tank wagons were being built with steel solebars. The titular owners were Basic Slag & Phosphates Companies but they were in fact largely owned by Baldwins Limited. The firm operated from Lilleshall Street on the East Usk Branch and is listed in the 1938 Johns’ Newport Street Directory. It made fertilisers from a mixture of phosphates and powdered slag which was a waste product from iron making.

My first problem soon made itself apparent: I failed to find a photograph of the prototype, though I searched my extensive PO wagons index, the standard book on tank wagons by Tourret, and Joe Greaves’ estimable listing of published private-owner photographs, which you will find on the Black Dwarf Lightmoor website.

So I was obliged to take the lettering style of the transfers and the supplied livery information on trust, as the instructions have neither diagrams nor photographs. I do not know if the livery was lost during the World War II pooling, or if the wagon was regarded as non-pool. Reluctantly I started the build, worried about constructing a vehicle which might not conform to prototype.

The text-only instruction sheets are easy to understand, so it’s not hard to work out what goes where. I deviated from the suggested order several times, but no doubt you’d get a finished model just as well if you go by the maker’s sequence. The white metal castings were clean, and the etched parts nicely done. My principal complaint is with the quality of the resin castings. The underframe was banana shaped, and though the instructions claim that any distortion can be solved by immersing the casting in hot water and manipulating it back into shape I found that the distortion returned once the part had cooled, even though I placed a heavy metal box on it overnight. The instructions claim that once the tank body is added to the underframe any distortion will disappear. That seemed to me to be doubtful; three-leggedness was a likely outcome when I came to fit the wheels, and so it proved as we shall see.

So work began with the resin parts being scrubbed first in soapy water to remove any releasing agent. A job worth doing at this early point is to file any casting flash from around the resin spigots on the rear of the solebars, which are the fixing points for the W-irons and the V-hanger mounting plates, and to have a dry run with the W-irons to see if the holes on the etched parts will fit.

Mine did not and needed enlarging with a rat tail tile. I did not spot it needed doing at an early stage and it was much more difficult to do after the tank was in place on the frames. In retrospect it would also have been better to file the etched holes into a vertically orientated oval as well, to give a millimetre or two of adjustment when fitting the axles. This would help to ensure that all four wheels sit level. No provision is made for a compensated chassis, so it’s vital to have the axles parallel in both planes. It’s easier, too, to drill the witness marks for the tank lashings 1mm while the frames and the four cradle pieces are still separate.

The other large resin casting is the tank. This had prominent mould lines needing filing off, and some of the rivet detail around the ends was missing where the edge of the resin was crumbling. Holes in the tank for the various white metal fittings need drilling out 2mm, and the tank ends need gluing to the tank barrel. I toyed with the idea of air-brushing the body before assembly as suggested, as it is probably a different colour from the underframe, dark red according to the instructions, but eventually I decided to wait, in case the paint finish was damaged by subsequent handling of the body.

Don’t forget to fix the metal casting for the lower discharge valve to the underside of the tank now. This is impossible once body and frames are united. I added the four resin cradle pieces to the frames with superglue, then smeared both the tank underside and the curved areas of the cradles with Evostick and let the glue harden for 10 minutes, before bringing the two components together, and then binding them tightly with rubber bands, flooding the cradle/tank joints with runny superglue. I then left it all to harden for several hours. Later inspection showed that one cradle had separated from the underframe as the glue joint had failed under the tension of the frame distortion.

So, more glue, and more rubber bands…If I had painted the tank this process would almost certainly have damaged the paintwork. Even after all this, the solebars were still neither straight nor parallel.

While the glue was setting I got on with assembling the sprung buffers. The injection mouldings appear to be identical to the Parkside product for ribbed RCH buffers. The capping rings were added to the buffer ends with Plastic Weld and allowed to dry, and the barrels were cleaned out slightly with a rat tail file. Tiny internal springs are threaded over the steel buffer stems, which are then inserted in the barrel, and 14BA nuts secure the stems in place. A dab of Loctite or superglue will prevent the nuts coming undone. The end result is excellent.

The headstocks holes needed to be enlarged a little to accept the buffer bodies. It was easier to fit the couplings before any further underframe detailing is done, and it would have been easier still if the headstock had been a separate component. I put the two rather thin hooks provided on the etch into my spares box and substituted four spare Acme brass hooks sweated together in pairs to form a chunkier alternative. Springs and split pins are provided, and fitting them is quite tricky as the space between the frames is narrow. I gave up on the split pins, and cut a longitudinal slot in each coupling shank so that two tiny rabbit ears could be twisted with snipe-nosed pliers once the spring was in place, to prevent it from escaping. I also reduced the springs in length by about a third; as supplied they were too long to fit on the buffer shank and still leave any room for compression.

As I feared, getting the wagon to sit level with all four wheels touching the rails proved problematical. I had three attempts before I cured the problem and it had all four paws touching a flat surface; stale superglue had to be scraped off each time. If I were making another I would file one of the four holes for the bearings into a slight oval to give a little vertical adjustment, as well as enlarging the holes in the W irons as described above. I soldered three axleboxes to the W-irons but superglued the fourth, to give me a few seconds to adjust its height before the glue grabbed. When I fitted the spring castings, I made sure the small bolt heads on their suspension brackets faced outwards. There is no etched detail for axlebox keeper plates, so I added four pieces of Microstrip to represent them, with tiny cubes of very fine Microstrip to form the bolt-heads.

The two smaller folds on the V-hanger mounting plates need to be made with the half-etched lines on the outside of the fold and the longer V fits behind the frame, the shorter one being at the front. I wanted to add the V-hangers to the mounting plate with solder for strength, but I was not quick enough with the soldering iron and the heat caused the superglue holding the mount to the rear of the solebar to fail. So I cleaned the old glue off and soldered the two Vhangers to the mounting bracket as a separate sub-assembly before re-gluing.

The brake-shoe/pushrod castings have vertical limbs which are slightly too long. I had a trial run to see how much needed to be removed before gluing them to the cross-frames.

The limbs should not protrude above the top edge of the solebars. The curved face of each shoe needs to be concentric with the wheel rim, and the push rods should be orientated right rod over left on both sides of the wagon. I used a piece of 1.3mm copper wire salvaged from an old mains electric cable to link the pushrods to the v-hangers. The holes in the V’s did not line up precisely with the hole in the casting, so a little fettling was needed. These are ‘either-side’ brakes, so there is no transverse rod beneath the wagon to connect the opposing pairs of V’s.

The kit provides four well-designed curved etched safety hangers for the pushrods, but I discarded them, as without a photo of a specific Basic Slag wagon to work from I could not be sure that the curved type is correct. As straight safety hangers are more common on tank wagons of this era, I made some up from scrap brass strip. If I had known when I bought the kit that I would be unable to find a prototype photo to work from I might have had second thoughts about the purchase. The brake levers need to be cranked in two places to clear the axleboxes, and I curled the end of the handle to form a shunter’s slot. The lever guides/ratchets were folded up and sealed at the top with a little solder. I then soldered them to the front of the cast springs (being quick to avoid damage to the white metal) rather than trust a superglue bond beneath the solebar as this part is vulnerable to handling.

Some guesses, which may or may not be right, had to be made about the siting of the diagonal wire stays and the tank lashing straps, and I did not exactly follow the model photo on the box lid (which you’ll recall was of a different company’s wagon anyway). The etched strapping bands are short by several millimetres and did not reach the cradles once curved to shape around the tank body as the kit’s makers intend. So into the spares box they went and I set about making longer replacements. I deviated from siting them as instructed, as most photos I could find of wooden framed wagons showed strapping bands further outboard and attached to the solebars, not to the cradles. Two lengths of scrap brass strip were substituted, which needed to be exactly 104mm. A 1mm hole was drilled at each end, and two pairs of snipe-nosed pliers were used, one to clamp the strip and the other to induce a 90 degree twist 5mm from each end. New 1mm holes were drilled on the top edge of the solebars 6mm outboard of each transverse beam, and I glued a tiny brass eyelet in each hole, parallel with the transverse beams, not the solebars. These came from a Slater’s coach kit I think. A shortened split pin would also do the job. The eyelet and the ends of the lashing strap were joined by threading a short length of 0.45mm wire through the holes to represent a fixing bolt, and securing them with a rapid dab of solder. There was not quite enough 0.7mm brass wire in the box for all the bracing wires, and it had been curled to fit the packing so it was difficult to get the upper horizontal stays straight.

Some 0.9mm straight nickel silver wire was found to form the diagonal stays. I glued the cast end stanchions with the base of their limbs level with the base of the headstocks, as per prototype, but then found that the lower holes in the stanchions did not line up with the holes in the resin tank cradles. The stanchions required redrilling before the lower horizontal wire stays could be fitted. I added four tiny mounting points from a sliver of mains wiring sheath, (the tiny red rings visible in my photos of the naked wagon). I also deviated from the instructions by at first mounting the diagonal bracing wires with their lower ends fixed to the top of the solebar, not the cradles, though this was changed again later.

No mention was made of horse hooks, but two dimples were found towards the left hand end of each solebar. These were drilled out 0.8mm and a U of 0.7mm wire inserted. The distinctive Charles Roberts deckle edged maker’s plates are not moulded onto the solebars, nor supplied on the brass etch so I filed up a pair from scraps of brass and glued them right of centre on the solebars. Build time to get the model to this paint-ready stage was about 10 hours.

The instructions say the kit has ”been designed to enable the model to be built with the minimum of effort”. I would not in all conscience recommend it to a beginner as there is significant rectification work to be done, though it can be made into a tidy representation of a tank wagon. An intermediate level modeller should be able to overcome the difficulties encountered along the way.

The model was given a thorough wash and left to dry, and then the underframes were sprayed with a black satin aerosol.

However, I had become increasingly uneasy about building and painting a generic or hybrid tank wagon which might never have existed. But that very day two photographs turned up on a local-interest page of Facebook (which sadly I cannot reproduce here as I do not own the copyright). They showed several Class B black tank wagons in War Department livery at Crumlin, one from the 1950’s and the other from about 1969. These were probably on a working from the Royal Ordnance Factory at Glascoed, near Pontypool. Shazam! - The penny dropped, light dawned, scales fell from my eyes and angels sang. The later photo showed three wooden-framed wagons which were almost identical to what I had built. The only major visible differences were that there was no ventilator on the top of the tank near the end and the diagonal stays were fixed to the face of the solebars, not to their upper surface. The decision was made; against all the advice of the old adage the horses would be changed in mid-stream.

The Basic Slag transfers would go in the spares box, and with a minor modification to the diagonal stays and the valve I would end up with a reasonably accurate wagon, albeit not belonging to the firm I had originally planned to construct. The single colour black livery would also obviate the need for a lot of tedious masking to get a dark red tank on black frames. The diagonal stays I had lovingly crafted were ripped off and replaced with new ones mounted on the solebar fronts as per my newly discovered prototypes. The offending tank ventilator was also removed and the resulting hole filled with a cylindrical plug of white metal scrap sprue.

The whole wagon then got a coat of black satin aerosol. Several WD photos in Tourret’s book on tank wagons helped flesh out the siting of the lettering. Transfers came from the HMRS Pressfix range, SR sheet 13 for the ‘W’ and ‘D’ and LNWR sheet 16 for the running numbers, ‘T’, ‘TARE’ and smaller numerals, with the stars and the WD arrow logos in white ink applied with a mapping pen. Running numbers were not clearly visible in the photos so ‘324’ is notional. Next, a coat of thinned Wilkinson’s exterior matt varnish was applied with an airbrushed. I added a few drops of Humbrol 98 matt chocolate to the thinned varnish to tone down the jet black.

Weathering was done with powders and a little judicious dry-brushing of various Humbrol earth colour enamels, with a final ‘grace note’ of spilled fuel running down the tank sides, executed with a few brush-strokes of gloss black paint. I was pleased with the end result. It’s fairly accurate when compared with a real WD wagon, but sadly my planned layout still lacks a ‘Basic Slag’ wagon. If anyone knows where I might find a photo of the real thing I would be indebted to them.