Slaters' Midland Railway 4-wheel brake van

by Russ Elliott

Although I intended this Slaters kit to be a 'quickie', it turned out to be anything but.

Being a brake van, I did not want the thing to be free-running, as would be given with normal pinpoints running in outside bearing units, and thus chose to use MJT inside bearing suspension units to provide the compensation. They are barely noticeable on the finished model owing the presence of the footboards at axleguard level. Some modellers even resort to foam pads rubbing on brake van axles, so that they really do hold back the whole train, thereby minimizing the tendency of the train's freer running pin-pointed stock to joggle back and forth.

The use of inside bearing units avoided the need to introduce excessive clearance between the outside W-iron/axlebox and the footboard. The moulded W-irons supplied as part of the kit's solebar mouldings could therefore be left in place.

Body details

I found that the floor needed widening by 0.5mm to get the sides and ends to fit properly.

Bufferstocks were drilled out for the later fitting of Alan Gibson heads, springs and long bushes.

The roof was thinned down nearer to scale thickness (I hate seeing an overthick roof). The kit's chimney is conical and was replaced by 1mm plastic rod, drilled out just at the end, and extending down through the roof with a makeshift stove attached to the bottom.

The thickness of the compartment ends in the window area was thinned down to approx 0.25mm. A door handle and catch was added from 0.25mm phosphor-bronze wire.

All moulded handrails were replaced by 0.33mm brass wire with the handrail end rivets being simulated with the same material.

The vertical planking as supplied on the kit sides is incorrectly extended to the bottom of the sides – there should be a single horizontal runner. On the model therefore, the bottom 1mm of the sides was milled off and replaced by a horizontal strip of 5 thou plastic. Train indicator racks were added to the sides with 10 thou plastic, thinned down. The open, 'cabin' end headstock handrail was replaced with 0.5mm nickel-silver wire. The lower inside section of the verandah end was replaced entirely to provide the inset shown on the prototype and to feature the characteristic sloping section at the join of the planking and the headstock. Planking was scribed on the inside of the verandah end. The height of the verandah top is approx 1mm too high on the model – this fault is present on the kit, and was not detected until too late – I should have looked at the drawing! This has correspondingly resulted in a slightly incorrect vertical placing of the side handrails. Verandah 'guard' handrails were added. Triangular section plasticard was added between the body verticals and the floor in the area of the verandah ends – these fillets appeared fairly early on in the career on these vans, and are intended to stop rot. Lamp irons were added from plasticard, three pieces on each one for the characteristic MR pattern. Extra rivets were added where necessary to the body and to the solebars and headstocks.

Coupling hooks are the excellent MJT white metal castings, and for you 3-link fans, are man enough to be functional, providing they aren't subject to abuse. You will find though that the hole needs to be enlarged slightly and very carefully to take the toroidal shape of the 18 thou diameter of a coupling link.

The roof is removable, as I don't like to put glazing in until the body painting is more or less complete, and is held on by two 10BA bolts. Having a removable roof also means that body weighting can be left to a later stage.

The incorrect square section footboard supports on the kit were replaced by approx 0.7mm diameter nickel-silver wire. Footboards were thinned to scale thickness (about 25 thou seems right). The lengths of the upper footboards should be different, and new ones were made for the balcony end, since those in the kit are not long enough. An MR nameplate was added to the solebar, together with horsehooks.

Axleboxes: those in the kit were replaced by Ellis 10A (MJT castings), as this type appeared to be more common in later days for these vehicles.

Chassis units

3'7 1/2" wheels (split-spoke, Alan Gibson) do give clearance problems between the wheels and the floor underside (set at 4' above rail level). Fortunately, the MJT inside units can have their legs tweaked out to cope with the P4 back-to-back, but even so, with a 3'7 1/2" wheel, the top of the fixed unit is 15.7mm above rail level. The rocking unit top is 16.5mm above rail level, and with the floor (which on a brake van cannot be raised up inside the body) thinned down to 0.25mm (not easy, considering that there are planking grooves scribed on top!), the buffer height can just be on 14mm, which is within my specification, but probably above the prototype design level, which on MR vehicles at the time, was 3'4 1/2" (13.5mm). If I were to do the vehicle again, I would discard the Colin Waite style 'rocker' in favour of putting the rocking unit on a pivot rod, thereby greatly easing this height problem.

I could not get the Alan Gibson split-spoke wheels to run concentrically, and bushing is precluded since there is not quite enough meat in the middle of the wheel moulding for this; in the end, the best I could manage was to fit new axles of 3/32" diameter, the new axle hole being bored through the wheel moulding while the tyre is held and rotating in a specially turned lathe collet.

One problem that did not become immediately apparent, and which caused a real headache, is that the brake shoe hangars, all of which are suspended from a complex plastic framework (60 thou square material) mounted on the inside suspension units, obscure the tails of the sprung buffers as they protrude through the rear of their collar guides set in to the rear of the headstocks. Since the pre-paint washing can rust the steel buffer springs (and shanks), I like to fix the buffers after painting, bending over the tails of the shanks at the appropriate point (to stop them dropping out of the front). With the tails obscured, the suspension units had to be made as complete assemblies with all the brake gear attached – these could then be washed and painted and inserted into the body after the body final painting stage and buffer insertion. In future, I might chose fully-assembled push-in sprung buffers, but Slaters headstock mouldings are excellent and are so easy to spring.

The prototype has a very short solebar length in relation to the wheelbase, so there was very little room to fit the AJ coupling mounting lugs and their shank height/centring guides between the headstocks and the brake shoe assemblies mounted on the inside suspension units.

Brake shoe rods are 20 thou plastic rod, while the central brake rod is 30 thou plastic rod – a crank and extra rod attached to the central rod depict the connection to the brake handle inside the body. Full brake gear attachments to the brake shoe rods was not incorporated – I draw the line somewhere!

Currently, the vehicle is about to go into the paintshop.

References

An Illustrated History of Midland Wagons Part 2, Bob Essery (OPC). Diagram 390.

© Russ Elliott

December 1998