Aug 13
Hello again, this time a little update on some of the O gauge range of rolling stock, North British Railway goods vehicles formerly part of the Port Wynnstay range.
First up, PW 7O4, the North British Railway designed Empty Cask Wagon (LNER diag 65B). A slightly unusual vehicle being something of a cross between a long wheelbase van and a high sided open. As the name suggests they were designed solely for the purpose of returning empty whisky casks and beer barrels to the many and various Scottish distilleries and breweries served by the North British Railway. As a load of empty barrels is essentially high volume but low density, the wagons were lightly constructed with slatted sides and ends, and initially rated at just 8 tons.

Kit PW 704 represents the first form of these wagons, fitted with conventional hinged doors (often referred to as cupboard doors) and a single pair of 'T' section straps which gently curved across the top to act as ties preventing the top rails from bowing outwards when fully loaded. As barrels were typically stored outside at the breweries, there was no need to protect them from the elements during transit, thereby saving the expense of a full roof.
The second kit is PW 7O5, the younger sibling of PW 7O4 in that it represents the later development of the cask wagon (LNER diag. 67B). These shared a similar slatted bodywork to that used on the original wagons, but were provided with sliding doors that would have been more convenient to use in the tight confines of goods sheds and loading bays.

Below deck, these vehicles had thicker journals and stronger springs permitting higher loading, initially 10 tons and later 12 tons. This higher rating enabled them to work both ways, carrying both full and empty casks, thereby making much more efficient use of the vehicles. Two pairs of 'T' section roof straps were provided to constrain the sides, reflecting the heavier load. Not being common user, these wagons would have rarely strayed outside their native territory and as such are a signature item of rolling stock for Southern Scottish pre-nationalisation layouts. A handful of the heavier rated wagons survived into the early period of British Railways, some photographs showing them converted with oil axle boxes.
In a slight change to the original Port Wynnstay kits, these are now supplied with cosmetic resin axle guards rather than the white metal ones previously used. The wheels are then carried in an etched brass compensation unit (not supplied). This is what I have been advocating for some time for use with my O gauge Coach Builder packs. There are various manufacturers that supply this type of unit, with different degrees of sophistication and complexity to suit most tastes. On these test builds I used units supplied by CRT kits. I must stress this is not an explicit recommendation, they were merely selected for being relatively simple and economical. Initial test running has confirmed that the track holding of these longer wheelbase wagons is vastly improved by the use of compensation.

I should however point out a couple of potential pitfalls that might catch out the unwary. Firstly, there were no instructions provided with the etch, so it helps to have some experience in order to know what you are doing -these are internal bearing therefore you will need to dismantle the wheelset and cut off the narrow ends from the axle. Secondly, the axle hole is etched over size so you will need to source a suitable bearing appropriate to your axle diameter. In this case the issue was solved by slicing some rings of K&S brass tube and soldering in position to act as bearings. When the compensation unit is folded up, a pin or piece of thin wire is used as a pivot allowing the unit and axle to rock very slightly. Before fitting to the wagon, the ride height was adjusted by using plasticard shim between the compensation unit and the underside of the floor.
The second axle of the vehicle should be fixed. This can be achieved by either drilling the back of the axle boxes and fitting wheel bearings in the conventional manner, or by using another compensation unit, but this time locked up with either solder or glue to prevent rocking. This is often referred to as 3-point compensation as the principal load bearing points form a triangle. One additional benefit of the CRT unit is the various bits of brake gear that is included on the etch - always handy to have in the spares box.
The third vehicle in the ex NBR trio is PW 701. This is a large 6-wheel covered van rated at 15 ton (LNER diag. 44B). These handsome vans were in some ways simply a stretched version of the contemporary 4-wheel vans in use by the company at the same time. Originally introduced in 1904, the first vehicles of this body style featured a flexible wheelbase, using a fixed centre axle and two outer pony trucks. The diagram 44B vans were a later build arriving in 1921 but using a fixed wheelbase chassis. Many of the earlier vans were subsequently converted to the rigid form.

In rigid form and with oil axle boxes, a good number of these vans survived into the early BR period where their internal capacity and long load length must have been an advantage. Photographs suggest they were widely travelled, with examples in BR days being captured at both Neasden and Cambridge.
The test build model shown here attempts to depict a vehicle in BR light grey livery. The running gear once again makes use of CRT compensation units. The outer units are allowed to rock, whereas the centre unit is fixed, creating 3-point compensation either side of the centre axle. The centre unit was first modified to be narrower to allow for a greater degree of side play on curves. The exact minimum radius is yet to be established. Before the roof was fitted, a small amount of weight was added inside the body at each end.
I feel I should add a note on lettering and numbering. The cask wagon models shown above are in an almost finished state. Lettering still required includes 'return to' instructions adding to the lower right side, together with 'cask traffic' or 'ale traffic' branding. The numbering of all three vehicles here is illustrative rather than strictly accurate. It is my understanding that the numbering policy used by the NBR was somewhat ad hoc and ultimately disjointed which makes placing individual vehicles or tracing number sequences very difficult. Some sample numbers can be determined from photographic evidence, but in the case of the 8 ton empty cask, I do not currently have that information, hence the 1234 on the number plate. Personally speaking, I am becoming increasingly minded not to finish rolling stock with numbers that have appeared in published photographs, lest they should attract the unwanted attentions of obsessive 'rivet counters' which can get very tedious. As such I have tried to create numbers that are at least plausible, in line with general company or regional practice. If it turns out I have made an error, they can be changed at a later date. As far as rolling stock on layouts is concerned, if it looks something like and most importantly creates the right atmosphere, then I'm happy with that.
The kits featured above will be added to the website shortly when the first batches of parts are ready.
Finally, we do not have any shows booked for the remainder of this year, which in theory at least, should allow a little more attention to be directed to the web shop. That said, I will however be attending Guildex this year as part of the operating team with our club layout 'Invermire'. Its blue diesels in the Highlands, completely different from the day job. The distillery in Invermire is served by imposing bogie bulk grain hoppers, and the products taken away by road, so sadly no requirement for cask wagons.
If you are around at Guildex, stop by and say hello.



















