Ken Gray
Pictures by the author

THE KIT I DECIDED TO BUILD is a 7mm O gauge kit for a Great Northern 6-wheel composite coach to diagram 156. The kit is produced by D&S models and has been on the market for many years. The kit consists of an etched brass body, chassis parts, whitemetal axleboxes, springs, roof fittings, brake pipes and a plastic roof moulding. The modeller must supply the couplings, wheels, door handles, interior seating, floor and compartment partitions.

The finished coach between two others I made earlier.

The kit has three main sections: the chassis, the body, and the roof. As is usual with a lot of kits, access to prototype information is very useful to producing a good model.

Before modellers of the diesel era ignore this article, please note that some of the techniques are applicable to more modern stock; and that 6-wheel vehicles such as stove Rs, and Thompson 6-wheel brakes, survived well into the 1970s.

This article does not cover the basic techniques for building etched brass kits as they have been covered in other places. The article focuses on the D&S six-wheel coach.

The instructions for assembling the chassis are reasonable, although not the best on the market. The main floor etch is folded up with overlays added for the solebar and the bufferbeam detail. I tinned the overlays before sweating them onto the folded floor. The top footboards are part of the solebar overlay etch and need to be folded up. The fold needs to be made carefully as the lower footboard etch also provides the footboard brackets. These brackets need to pass through the gaps in the fold between the solebar and the upper footboard in the solebar etch at the bend between the two. Most experienced modellers add strengthening to the footboard brackets as they are vulnerable to damage. I usually solder brass rod behind a couple of the brackets to strengthen them.

Part built chassis showing equalising beam between the left hand and centre axles

The W-irons for the centre axle are on the outside of the solebars. These are made from a plain etch with a detail overlay and are soldered to the outside of the solebar. Various tabs need to be folded out from the floor unit to form the suspension and hangers for the brake equipment. The centre axle runs in bearings that are inside the wheels formed by a carrier to allow sideways movement. The ends of the centre axles outside the wheels need to be removed.

As designed, one end axle is fixed and the other end axle can rock side to side. The centre axle can slide, rock side to side and is sprung by its mounting wire. All the movement is provided by a wire running most of the length along the centre of the chassis. It acts as the pivot for the end axle with the rocking motion. It also controls both the side to side and the up and down movement of the centre axle.. This arrangement works well but I prefer to modify it slightly.

I provide a bracket from scrap etch, halfway between the centre axle and the end axle which has rocking motion. This bracket acts as a pivot point for a shorter version of the central suspension wire mentioned in the last paragraph. This shortened wire is only long enough to carry the end rocking axle and the central axle. It is soldered to the central axle carrier only. The holes in the brackets for the end rocking axle are opened out in a vertical direction to give about 1mm of vertical movement. The shortened central wire then acts as a compensation beam, provides the pivot for the two axles with rocking movement and adds a degree of springing to the centre axle. The picture of the underside of the chassis may help to make this arrangement clearer.

The suspension in this format allows the coach to traverse a 4ft radius crossover on my layout. It also appears to be able to negotiate PECO set track curves, although I do not have any laid permanently. The only problem with derailments that I have had with the four D&S 6-wheel coaches I have built has been with one end axle. I did not ensure that the outer rocking axle had enough clearance between one of the rocking axleboxes, and the back of the lower footboard. This was easily rectified by easing the footboard away from the axle box.

Parts for the brake rigging are provided. There are diagrams to help get the brake yokes, and other parts in the correct positions. The kit can be built as dual air- and vacuum-braked, or vacuum-braked only. I have built mine as a vacuum-only coach without steam heating. Castings are provided for the gas lighting tank ends. The tubular section forming the rest of the tank has to be sourced separately.

The body of the GN 6-wheel coaches produced by D&S is different from a lot of etched brass coach kits in that the lower body side has the bodywork panelling to be inserted into the main body-side, which is only a framework below waist height. The picture of the main body components illustrates this. The body ends are straight so there is no tumblehome curve to be formed in the body ends. There are various ways to form the tumblehome in coach sides. The body end is usually used to check the profile of the coach sides. My usual method of forming the tumblehome is to use a piece of large dowel, or a hammer handle. The dowel is useful for long lengths. The hammer handle is useful as it has numerous different radii. I gently bend the coach side round the curved object repeatedly checking the resulting profile against the coach end at various points along the coach side. This method may make the experts cringe, but it works for me. For the GN 6-wheel coaches I bend the main sides first, then the lower side inlays to match.

The body sides have upper, and lower flanges that need to be bent. The upper flange is a 90-degree bend, but the lower one is a bit less, because of the tumblehome. I use bending bars to achieve an even bend. If you do not have access to bending bars, then bends can be made in a vice. If using a vice, do not bend each section in the vice to the full 90 degrees in one go, Bend each section a little, then bend the rest of the flange a similar amount, before going back to bend the first a little more. This will avoid stretching the brass too much. If the brass is stretched, then the flange will have wrinkles in it that are impossible to remove. The door window-surrounds and door hinges, which are separate etchings, are added before assembling the coach body. This picture shows the sides ends with two of the compartment dividers.

Partially detailed body side and ends with two of the compartment partitions.

A lot of the detail on the ends is added before joining the ends to the sides. It is easier to get things like the steps soldered at the right angle when the end is flat. Holes are provided for some body end handrails but not for the curved upper ones. These holes are easier to drill with the body end flat before assembly. The handrails are formed of brass rod. It can be awkward to get the curves on both handrails to match each other. I usually curve one, and then use that as a template for the other, but remember they are mirror images.

The body sides and ends are joined on a flat surface, checking that everything is square. The instructions recommend that a strengthening brace is put across the top of the body mid-way along the upper flanges. This needs to be positioned so that the compartment dividers, and the seats can be inserted. The body is fastened onto the chassis by a nut and bolt through the lower flanges at each corner of the body. Care needs to be taken to get the nuts soldered to the top of the flanges so that the body lines up with the chassis and so the bolts are clear of the buffer retaining nuts.

Door and grab handles are not provided in the kit. The door handles are available from other suppliers but I usually make my own. A piece of 0.7mm brass rod is formed into a U shape with square corners. The legs of the U are the right distance apart to fit in the grab handle holes in the coach sides. The U-shaped brass rod is then placed in a vice with the flat bottom of the U protruding out of the vice. I use a gauge to set the height of the bottom of the U. The bottom of the U is then hammered over flat with a pin hammer thus forming the upright of the grab handle.

No coach floor or compartment dividers are provided in the kit. These can be made using 0.040in plastic card. Making the floor is a simple case of cutting a piece the same size as the bottom of the coach body. Then make cut-outs in each corner to clear the body fixing nuts. Before starting on assembly of the body, I use one of the body ends as a template to cut the compartment dividers and the profile cross members to strengthen the roof. Some people like to make a full interior for their coaches, but I do not go that far. The interior of compartment stock is not that visible, so I just provide seats. Seating mouldings are available from suppliers.

Basic coach interior.

Glazing is added after painting. The door window-surrounds are separate etchings, resulting in three pieces of glazing being needed for each compartment per side. The glazing is glued in place using canopy glue or similar, not super glue as this can cause misting of the glazing. A representation of the passenger alarm system was made from 0.5mm brass rod, with boxes from plastic card on the coach end not fitted with steps.

Roof gas pipework under assembly

The main roof is now supplied as a plastic moulding. Earlier models had a profiled wood roof. The plastic moulding has to be cut to length to suit the type of coach. It also needs to have flanges on the side trimmed back to suit the type of coach. Profile cross members were cut using the coach ends as templates to help the roof retain its shape and to enable the roof to be a firm fit between the ends. The roof was covered with cartridge paper to provide the texture of the original canvas roof.

Ventilators and gas lamp tops are supplied with the kit. The vehicle I am modelling was one supplied second-hand to the M&GN. Photos appear to show that the number of compartments with roof mounted ventilators varied on the M&GN. I did not have access to a photo with a clear number, so I have fitted all the compartments with roof ventilators. Gas lighting on the M&GN originally used the single pipe system before changing to the two-pipe system that allowed a pilot light to be permanently lit. The changeover date between the two systems is unclear. My coach has the single pipe system. The gas pipe is very a prominent feature on the roof. No parts are provided for the pipe so mine is made from 0.5mm brass rod soldered to short lengths of brass strip.

The first picture shows the gas pipe assembly being built. The end of the long strip is soldered to the rod before being cut off to form the pipe mounting blocks. The second picture shows the roof details and the profiled cross member with packing pieces for a firm fit between the coach ends

Roof showing gas pipe.

The first step in painting any brass model is to ensure it is as clean as possible. The coach chassis, and body were thoroughly cleaned using Bar Keepers’ Friend, and allowed to dry for 24 hours. A coat of Halfords self-etch primer was then applied.

The M&GN retained the bodywork teak varnish finish of the GN. The solebars were painted a teak colour. Chassis ironwork was black. There are various techniques to achieve a varnished teak appearance. The one that I have used starts with a coat of Humbrol number 7 Light Buff gloss. The next step is to apply Humbrol number 9 Tan gloss, which is brushed until nearly dry to achieve a streaked effect to represent the wood grain. The wood grain and colour variation is then enhanced using Humbrol number 110 Matt Natural Wood, dry-brushed on. Some railways used teak from different sources that was a slightly different colour. The degree of red or brown of the panelling can be altered by varying the colour used for dry brushing. The grain effect needs to follow the panel grain seen on the full-size coaches. The effect needs to be done a few panels at a time so that the paint does not dry evenly without the graining effect.

The bottom third panel from the left has had the tan colour applied. The first two bottom left hand panels have had the final dry brushing of natural wood. A coat of satin varnish was applied to the body after the lining and transfers had been applied. I mention the varnish here because it subtly darkens and deepens the teak effect.

The lining was done with a bow pen using Humbrol number 74 Matt Linen. Other people have used fine line writers to produce lining. The transfers are homemade which is an article in itself. They tend to come out translucent, so the lighter colours are overpainted with a fine brush.

D&S kits are perhaps not for the complete beginner new to brass kits. One of the Connoisseur wagon kits is ideal as a first brass kit. To build a kit like this you will need to source some parts separately from the kit. Prototype pictures and information are always useful when building models, and this kit is no exception. The D&S coach kits definitely do not fall into the complex or impossible to build category, they are possibly a third project in brass kit building. All the parts fit, go together well, and produce nice models. The completed model between two others that I have built is shown at the start of this article.

The three stages of producing the teak finish.