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16T mineral wagons – a bluffer’s guide to recognition

Gaining a grasp of the various designs of 16 tonner seems to be something that exercises the mind of many a modeller.  It’s true  that it can be a complicated business, but unless you really want  to get into the history for its own sake, it’s not obligatory to make it so.   I believe some of the confusion may be due, at least in part, to the usual (and admittedly logical) historian’s approach of outlining development of the type from its origins in the 1930s or even earlier.  So in order to try and break this down and demistify it, I’m going to go backwards – starting not from the end as such, but from the peak of development of the type by BR.

A healthy cornerstone in gaining understanding can be laid just by making the point that by far the biggest part of the total construction – perhaps as much as 80% – were virtually identical apart from relatively small details like axleboxes or buffers.  At this point the more well-versed of you might be muttering ‘diagram 1/108’ with a self-satisfied wee smile, and that’s why I’ve titled this page as I have.  Unfortunately though, the diagram itself is a bit of a red herring.  On the one hand, wagons to other diagrams like 1/111, 1/114 and 1/117 are in fact all-but identical to 1/108.    On the other, it doesn’t differentiate as to some pretty major differences occasioned by vacuum braking.  That said though, again in the interests of keeping it simple, this page only deals with unfitted wagons.

Anyway, let’s not get sidetracked by details so early on; the fact remains that BR, in very, very general terms, only actually built two designs of 16 tonner – welded or riveted.  The vast majority of 16 tonners throughout most of the beloved ‘transition era’ had welded bodies, top flap doors and unfitted Morton brakegear.  They were pretty much as per the classic Airfix kit, subject to one proviso mentioned below, and Bachmann’s 37 225 in its various guises is  in every way a RTR equivalent.

You might notice I’m not getting into the matter of doors as yet;  various different designs of both end and side doors were in use, but it didn’t of itself affect the diagram and repairs in later life often changed the position anyway.

The other design built under BR was given diagram 1/109 and is effectively the same pattern of wagon, but of riveted rather than welded construction.  These were much less numerous, by a factor of 10 or so.

Brakegear is something that can cause particular consternation to the unwary.  Again to simplify matters, the vast majority of BR wagons had, as indicated above, the Morton pattern.  This had pushrods and brakeshoes on only one side of the wagon, and the lever on the other side was connected to the braked side by a transverse rod.  The side with the pushrods/shoes also had a dog clutch, which was needed to reverse the action of the hand lever on that side:

Although it’s hard to get your head around from this shot, when the wagon is in the upright position, another recognition point is that these pushrods slope downwards from right to left towards the end door, as you look at the wagon from the side they’re mounted on.  As an aside and because many people will be so familiar with it, this is a point on which the well known Airfix kit is wrong – although intended as a ‘1/108’ (sic), it provides identical shoe/pushrod assemblies for both sides, yet has no clutch.

The immediate familial predecessors of the wagons just described were a large number of similar straight-sided wagons which had been built by or for the LMS, the LNER and the Ministry of War Transport from around 1945.  Again these followed the same demarcation between welded or riveted construction, but there were two main differences when compared with BR construction.

One of these differences was in the brakegear.  All pre-BR 16 tonners followed the precedents of the wooden PO wagons in having ‘double’ or independent sets of brake pushrods, one each side, very much like the RCH-pattern wooden 13T POs that they replaced. There were twin V-hangers on each side, which can just be seen in this angled shot:

Again it’s difficult to appreciate upside down, but on this pattern of gear the pushrods slope upwards from right to left, whichever side is viewed.

The other difference, which can fairly conclusively identify a wagon of pre-BR  design, is that these earliest straight-sided wagons didn’t have the familiar top flaps over the side doors.  However, that distinction again becomes slightly blurred around the time of Nationalisation, as a decision was taken at that time to incorporate the familiar top flap doors.  As the Morton brake wasn’t adopted at exactly the same time, this resulted in a fair number of wagons being built as a sort of transition between the two patterns just outlined i.e, they had the top flap body (either welded or riveted) , combined with the ‘double’ brake.  Unless they’re very near the camera, these wagons won’t be particularly evident in most photos, as they’ll look much like any other top-flap wagon.

The other possible fly in the ointment here is that from around 1970, BR completely rebodied many wagons again omitting the top flaps.  If the brakegear can’t be clearly seen, these could theoretically be confused with the earlier wagons.  However, there’d be only a small time window when both worked together as by this time those earlier wagons were very few in number; even more obviously, a BR rebody would be evident at that time by its fresh Rail Grey paintwork.

Although as I’ve said this isn’t a full treatise, two other very significant earlier designs should be mentioned.  One is the Chas Roberts patent slope-sided design, which apart from the very obvious body shape, follows the same general layout as a riveted MoT wagon.  The second is equally distinctive, the so-called ‘French’ type, which is very different in appearance in having ‘cupboard’ side doors and no end door.

For anyone wanting to absorb more, reference sources abound on these wagons but the one that I really would recommend is a three-part feature by Peter Fidczuk which appeared in the onetime Modellers’ BackTrack magazine, volume 1 parts 3, 4 and 5, from 1991.

Proportional representation

The other common question about mineral wagons is in what sort of proportions these assorted designs should be used, relative to both other wagons and to each other.  The following is of necessity a brief synopsis, but the raw figures behind it are available should anybody be sufficiently demented to want to know more.

Starting where the type came in, with regard to the replacement of the old RCH-pattern wooden POs and related types by steel 16 tonners, figures collated by Peter Fidczuk show an 80/20 split in 1950/51 in favour of the wooden vehicles, gradually changing over ten years until by 1960/61 it was the other way round, at 81% steel to 19% wood. 1962/63 shows a figure of 14% wood, and few if any would have lasted longer after that.

As regards the proportions of minerals vs other wagons, my take on this is that it depends what sort of a scene you’re portraying. It’s true that in terms of total wagon stock, minerals vastly outnumbered other wagons (even in the case of common-or-garden merchandise vans, probably by something like 10:1), but this doesn’t take account of the way mineral traffic was worked.  The tendency was for it to be almost a separate traffic until it got to the pick-up goods stage, and I’d suggest that that 10:1 ratio is only relevant if you’re modelling a main line or industrial area, where coal-class wagons worked in block train lengths.

Another key query is the proportions of the various types of steel minerals relative to each other. As a starting point, it’s kind of obligatory to think about the overall total:  here, Peter Fidczuk gives a total figure of 330,000 16 tonners built, but that will include all the oddities in design terms, like the slope-siders and the so-called ‘French’ minerals. A big part of the problem though is that the disposition of this massive fleet was constantly changing.  The very oldest designs of steel mineral were beginning to be weeded out at probably the same time as the newest ones were being delivered, and many of the less standard types followed over the next ten years or so.

Whilst writing the BRM articles, I tried to work out a reasonable estimate for the mid-1960s (by which time a lot of the stranger vehicles had been withdrawn), of what part of the 16 tonner fleet would have been to the (sic) ‘1/108’ type, i.e. BR-built, welded with top flap doors and Morton brake.  By a blend of counting from reference sources, intelligent guesswork and gut feeling, I arrived at a figure of probably 80% being this ‘standard’.  The earlier designs are something that I have devoted a little more time to lately- I’d not call it research as such, more a very rough calculation of how many of each type were built in order to pay lip service to this idea of proportion.

Going back a little into the beloved early 1960s ‘transition era’, perhaps a slightly smaller percentage, say six or seven out of every ten, should be of that ‘1/108’ pattern.  Now a ten wagon train is numerically convenient and will fit on most average layouts, but it’s an awkward figure to work with – statistics being what they are, it will sway the averages too much towards the oddities.  So let’s double the figure and consider a 20-wagon train; I know not everybody will have room for that many, but it’s not that long and it will make the maths easier.  So the ‘1/108’ and its equivalents could number, say, twelve out of the twenty.

Of the other designs, firstly and probably most significantly as they lasted well into the 1970s, are the BR-built riveted wagons (reliably to diagram 1/109 with a few exceptions).  These numbered very roughly about 25,000, and could conveniently account for another two in the twenty.

After that in the reckoning come the LMS, LNER and MoT wagons; as explained above, these were built in welded or riveted varieties and dependent on build date, could come with or without top flaps.  It’s difficult however to put a really precise figure on how many had top flaps, because production changed over from the old to the new designs during build runs without it being precisely documented.

Nevertheless, of these pre-BR straight sided wagons, the welded body without top flaps was easily the most numerous group, and as well as MoT wagons of diagram 1/102, it also included LMS wagons to D2109.  A combined figure for these two types gives a figure which, give or take a thousand or so either way, is in a similar ball park to the BR riveted wagons, and which could therefore account for another two in the twenty.  So we’re now at 16 wagons.

Stats for the remaining wagons produce smaller totals. The riveted pre-BR wagons (1/103 and 1/105) suffer from the same vagueness re- the changeover to top flaps, but again at a reasoned guess I’d reckon on a combined total (of wagons both with and without the top flaps) of maybe 10 – 12,000.  That’s another one in the twenty.

Now we come to the larger part of that ‘transition’ build, the welded top flap wagons with the double brake built for the MoT (diagram 1/104) and the LMS (D2134).  It’s also convenient to add to these the significant number of early BR builds that followed the same precedent, before the Morton brake was adopted, and consequently were really more akin to MoT wagons.   Again I’d put the quantity in this group excess of 20,000, so wagons 18 and 19 could be welded, double braked, top flap wagons.

Other designs that can be classified offbeat (i.e. not having straight sides, two main side doors and one end door) but still significant were the ‘French’ design and the Chas Roberts slope sided design, which was the subject of various builds for private owners, Roberts themselves and the final ones as part of post-war replenishment of the fleet before the straight sided designs gained superiority.  Totalling the above, but making a small allowance for these designs being the heaviest hit by early withdrawals, would allow wagon number 20 to represent this group.

To complete the picture, there were also some early 13T wagons (Butterley and the like),  some Cambrian 13 tonners, and a Hurst Nelson 14/16T design which isnt available as a model, would have been subject to early withdrawal and so can justifiably be excluded from this statistical exercise.

As I suggested earlier though, anybody who has an appreciation of statistics will tell you that they don’t work out as neatly as this.  To do true justice to this idea of proportional representation, and to represent all the significant types in so doing, you’d need to be running seriously large quantities of wagons (probably over 100).  Given the relatively small statistical samples that the stock on most layouts would represent, I doubt that exact percentages are all that crucial even if you did have the mental stamina to work them out.

To further illustrate this inexactitude, if you look at a few dozen photos you wont go very far before you come across evidence that seems to tell a different story.  For instance, it’s not at all unusual to find a formation with two slope sided wagons next to each other, or two non-top flap wagons right at the front. But as long as the majority of models visible at any one time are ‘standard’-ish vehicles, without too many one-offs and mavericks, I think the right impression can be given.

Edit 18.5.14:  I’m aware that this page, amongst others, gets occasional referrals from other sites, and that’s great because the whole point of putting it here was to help.  If more specific questions arise that it doesn’t address, don’t hesitate to add a comment to those below, or drop me a line using  this e-mail link,  and I’ll see what I can do.