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A Rake of Coaches: Or How Solving One Problem Leads to Another

John Mayne

 

It started out simply enough early in 2004. I saw the listing for a laminate brake standard on the Worsley Works web site and thinking it was a model of the 1958 brake composites, I bought the coach and a Deutz loco kit. I had been involved with the MRSI Loughrea group for many years and thought these models would give us a more accurate representation of the branch line in the “modern image era.” The only thing was that I was in the middle of planning a move to New Zealand!  So the Deutz and coach have never had a trip on the Loughrea layout. The Deutz is essentially a complete loco kit without wheels motor, detail castings and turnings, the coach basically consists of sides ends and underframe, the builder has to source roof, bogies, interior, detail casting and bogies. While the Worsley Works coaches are basically similar in design to Comet, the main issue is in forming a roof as most Irish stock is wider than the British; Comet and MJT extrusions are too narrow.  I model on 21mm gauge and while proprietary Commonwealth bogies might pass muster, I wanted the model to be as accurate as possible and bogies would require custom made side-frames. I was impressed with the detail of the coach and ordered an AEC railcar set, a Laminate second and a Park Royal coach: in for a penny,  in for a pound. Basically the idea was to commission any special components required such as bogies, roof extrusions or pressings and detail parts from UK manufacturers, to complete my own models and test the potential market.

Disappointingly, few of those I contacted responded or demonstrated a willingness to follow up on a serious enquiry for the design and  manufacture of components to compete the project. I had experimented with forming the roof profile variously from brass, plasticard and balsawood without much success, there is little practical guidance on scratch building coaches or metalwork in the contemporary model press. Commissioning an extrusion locally was prohibitive. Eventually I followed Allen Doherty’s suggestion of using a proprietary extrusion as a basis for cutting and filling to a wider profile. Bogies are based on MJT torsion bar compensation units which are easily adaptable to the wider gauge, and other details are a mixture of Comet and MJT components.

The Coaches:
Unlike the relatively rapid development of the BR Mk.1 stock, Inchicore like the GWR in the 1930’s, seemed to have difficulty in building two batches of coaches to the same design and went through several stages of development before the arrival of the Craven stock in 1963. Briefly the 1953-4 period  saw the introduction of a wide range of hauled stock based on a development of Bredin’s GSR flush sided timber framed designs, including open and compartment coaches, buffet, restaurant cars and mail vans. The earliest vehicles ran on GSR design bogies and traditional steel under-frames, later batches incorporated Bulleid triangulated under-frames and Commonwealth bogies. Even in the 1950’s such stock would have been expensive and labour intensive to produce and not readily adaptable to mass production, requiring a large highly skilled workforce to machine and assemble components. The Park Royals with their prefabricated components allowed volume construction using a semi-skilled workforce. Significantly though designed for suburban and main line use, only one design of body shell was produced.

1379 class Park Royal suburban coach

1379 class Park Royal suburban coach

The laminates (aluminium, insulation, plywood panel) are best described as of modular construction with several body designs (based round a small number of components), again allowing rapid construction. There appear to have been at least four designs: a brake composite, 70 and 64 seat main line standards and a suburban coach. I recall laminate coaches being refurbished at Inchicore in the late 1970’s. Each coach was stripped down to roof, ends and under-frames, and re-skinned; either CIE still had a stock of body panels or the manufacturing capability existed. One theory was that it was originally planned to replace the bodies after 20 years, but this was no longer required following the introduction of monocoque design in the 1960’s. Inchicore appears have briefly reverted to timber frame body design for its final batch of twelve coaches (ten standards and two firsts) before the arrival of the Cravens in 1963. Significantly these coaches used the heavier BR pattern of Commonwealth bogie.

The brake standard appears to be based on the 1970’s conversion of laminate coaches to brake standards rather than the 1958 brake composite design. The brake standards of this era were converted from laminate suburban stock and 1953-4 composites. The Worsley Works kit is of a different pattern and appears to be based on a conversion of a main line laminate standard. Two laminate brakes are preserved one the DCDR at Downpatrick, another by the RPSI as a service vehicle in their Dublin excursion train rake. The laminate standard and the Park Royal appear are to be accurate representations.

1448 class laminate standard

1448 class laminate standard

The etchings make up in a similar manner to the Comet coach kits, with the body sides and ends designed to be removable from the chassis. There is a half etched representation of the joints between the body panels, a distinctive feature of the laminates. The chassis comprises a main floor etching, with fold down truss rods, with separate etchings for solebars and a lower body stiffener making up into a nice solid chassis.  The solebars on the laminates and Park Royal coaches do not run parallel with the sides, the coaches running on Bulleid’s triangulated under-frames.  I have left well enough alone, though solebars, say from brass angle, could be set up in a jig to capture this subtle and distinctive feature of CIE stock of the era. The sides are easy enough to curve using brass bars and a straight edge. The Park Royal sides are etched in three sections with over lapping tags but are a bit flimsy being half etched.

Laminate coach - first section of roof in position

Laminate coach - first section of roof in position

I would rather use a formed sheet metal roof like the TMD Bredins, should a suitable one become available. I recently completed a C&L narrow gauge coach: forming the arched roof even with the down ward curving ends was simple enough, though forming a “modern” elliptical roof is a different matter and a subject seldom if ever covered in the main
stream model press. The etched brass assembly is soldered, and the aluminium roof extrusion glued in place using cyno reinforced with epoxy resin, with a strip of plasticard to reinforce the joint between the two sections of aluminium and support  the filler.

Laminate brake standard

Laminate brake standard

In the end on Allen’s suggestion, I used a Comet BR Mk1 roof extrusion cut down the middle the gap filled with body filler. The roof detailing covers a multitude of sins and lifts the model. Comet torpedo ventilators and PC lining strip  gives the roof its distinctive and  jointed appearance.  I decided to include a fairly high level of detail with door hinges, knobs, handles, toilet filler and communication cord pipe-work. Next stage is pattern making and castings for bogie side-frames, dynamo and vacuum cylinders, heating and  vacuum pipes, couplers, finish painting, build layout, couple up to B141!

Laminate coach sides clamped while glue sets

Laminate coach sides clamped while glue sets

Worsley Works underframe, MJT bogie compensation units, plasticard spacers for 21mm gauge, MJT LNER buffer shanks

Worsley Works underframe, MJT bogie compensation units, plasticard spacers for 21mm gauge, MJT LNER buffer shanks

Laminate coach with Comet seating units, plasticard floor and bulkheads

Laminate coach with Comet seating units, plasticard floor and bulkheads

There is also a lot of useful information on building etched brass coaches like these on the Comet Kits website: http://www.cometmodels.co.uk/ Follow the links: Downloads  Building Coaches the Comet Way.

[Ed: for more details see the following paper on coaching stock built for or by CIE from 1945 to the arrival of the Cravens: Kennedy D (1965) Modern CIE Coaching Stock Journal of Irish Railway Record Society 7 (37): 14-61]

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Hints on Putting Together Etched Brass Coach Kits

Jeremy Fletcher

 

Brass etch kits, or etching sets, provide a useful way to produce good quality models of non-mainstream or obscure prototypes which are not of interest to the larger commercial model manufacturers who need large production runs to cover the costs of specialised tools and dies.  They fill a gap between commercial models and scratch built models which many modellers may not want to attempt. Some people regard brass etchings as ‘hard’ as they usually involve soldering which is anathema.  Soldering is not really all that hard to do once you get started and gain some practice.   Basically it is just like using a liquid glue (Super Glue) which runs between the pieces to be joined.  The solder has to be melted to run by capillary action between the pieces and it sets when it cools off.  As for any glue, the pieces have to be clean and in the case of soldering the final cleaning of the metal surfaces is done by the flux.  The metal is first cleaned of dirt, oxides etc. using emery paper or filing. You could say the filing does ‘mechanical’ cleaning and the flux does ‘chemical’ cleaning. Oxides build up quickly on the hot soldering iron tip and need to be cleaned off regularly with a wire brush.  A potential source of complications occurs when soldering together long pieces.  Thermal expansion can cause warping or buckling.  It is best to ‘tack’ the pieces together in a few places; make sure they have not become buckled; and make corrections as required before going any further.  You may have to unsolder, let the part cool, clean off excess solder and try again.
 
There are various ‘suppliers’ of etching sets.  They generally supply few detail parts such as those mentioned below. Most modellers prefer to supply their own.  My own experience so far has mostly been with the Worsley Works coach etch sets and I can best comment on these.  These come as sets of etched frets and are really intended for use by scratch builders, providing hard-to-make parts such as panelled coach sides, fine grillwork etc.   Bogies, wheels, buffers, coach roofs etc. have to be arranged by the builder. Coach etching sets are generally provided with the walls, ends and floor but, typically no roof.   The floor may have fold down under-trusses and battery boxes etc. It is intended that the coach floor be made removable, held by screws, so that interior details and glazing can be put in after it is painted.  There are no instructions supplied with the sets and it is best to first study the various parts to visualise and decide on the procedures to follow and in what order.  The various sections should not be cut free from the etch frets until they are required for building up.  Care is needed when cutting them free to avoid unnecessarily bending and stretching.  The edges of the sections should be tidied up with a fine file so that they can fit up properly and cleaned where they are going to be soldered. 

The best way to build a coach ‘kit’ is to start with assembling the basic coach body ‘box’. The coach sides should first be curved if appropriate.   The ends can be used as templates for this.  The method of actually bending the sides is up to the discretion of the modeller. It can be done by bending around a suitable piece of pipe or such likes.  Care is needed to avoid stretching or wrinkling the thin etchings as it is difficult to straighten them again. The edges of the coach sides will normally overlap the ends at the corners.  To ensure that the corners can be put together square and also to make sure they are strong and rigid enough to withstand normal handling,  it is a good idea to put stiffeners inside the corners.  The stiffeners can be made from left over strip from the etch frets, bent into right angles.   They are soldered inside the coach ends, flush with the edges.  The coach sides can then be lined up against the stiffeners and first just soldered to these.  After any adjustments to get a proper fit,  the rest of the join can be soldered up.  The soldering is done from inside the coach to prevent ‘runs’ from spoiling the outside.  The coach body should be checked to be square before going further.

The coach body will typically be lacking in rigidity because of the soft flexible etchings and it will be necessary to add some reinforcing.   It is a good idea to solder in stiffener strips along the top edges of the sides.  These could be pieces of brass rod, or can provide a use for salvaged otherwise unwanted brass rail.  However, the coach sides may still be found flexible and it may be necessary to provide extra transverse stiffeners between the sides. A compartment coach will have interior partitions and these will help to reinforce a coach body.   Obviously it is necessary to avoid buckling when soldering on long stiffeners.

Making the roof for a coach is another story.   Normally no material is supplied by Worsley Works for making the coach roof.   It is very difficult to properly form a piece of sheet brass to the correct shape, particularly the more sharply curved edges without a special (i.e. expensive) bending jig. One could adapt a plastic roof from another coach, by (say) splitting it along the centre and widening it out or otherwise adapting to suit the etched coach body  It is possible to buy commercial wood lengths milled to various profiles and one these may be suitable or could be adapted to suit the particular coach.   Another way would be to make one’s own roof, either from solid plastic or built up from plastic sheet and strips or from balsa.  The roof when attached to the coach helps to make the assembly more rigid.

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