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Introduction

All of the loco kits that I have bought for my long term project are of types that were seen on the GN Derby line at one time or another, even if only once. That is, apart from the Ivatt class 2 2-6-2 tank, which forms the subject of this article. I currently have no evidence that one ever ran on the line, although Annesley based engines were very common. A couple were allocated to Annesley for running the ‘dido’ workmens’ trains so I chose one of those to model. This engine, 41280, was one of the push – pull fitted versions that were built in this form from new, so that would add some extra interest to the construction. My 4mm modelling career has almost entirely been based on the GC main line, which never really had any small engines, so I think that this is probably one of the smallest prototypes that I have ever modelled. The kit is adequate as it comes, but to enhance this kit I purchased a stack of detail items that included the push-pull fittings from Laurie Griffin. That’s a fussy decision down to my personal choice; I rarely build anything straight from the box. On opening said box, I found the usual selection of castings and etched sheets of brass in typical DJH style. A friend lent me his Scale 7 model of one of these engines for reference and of course it’s not best practice to copy another model, even though it does look very good. However, at least I could see how certain aspects of construction had been tackled.

Most of the large body and chassis soldering was done using fluxed 60/40 electrical solder in conjunction with phosphoric acid flux. Detailing work was carried out with 145 degree solder, which was also used for the large whitemetal joins. Brass parts were cleaned up with emery paper and if necessary, glass fibre brushes for the items with etched surface detail, although I really don’t like them, because I always seem to get annoying bits of fibre stuck in me. Small gaps were filled with cellulose knifing putty from Halfords.

I managed to borrow a copy of Ian Allen Locomotives Illustrated, number 72 (July- August 1990). Also, there was a good article in British Railways Illustrated, February- March 1992.

You’ve been framed

The frames are etched in a hefty grade of brass and a session was spent cleaning off the cusp from the etching process and comparing them with a drawing that I had obtained off the web (which seemed to come from the January 1948 Railway Gazette). They matched perfectly. As I like my engines to pick up on as many wheels as possible, on a small engine like this, the more wheels in contact with the rails the better. To this end I decided to run the leading and centre axles in sprung hornblocks and a set was duly purchased. I also decided to use the Griffin cast springs instead of the ‘silhouette’ ones etched as part of the frames. These would also act as keepers for the axleboxes in the hornblocks. The frame spacers were taken from the fret and cleaned up. The first few sessions were really cutting and measuring and working out how things would fit together and I was itching to set to with the soldering iron. After cutting out the openings for the hornblocks, the various spacers were soldered to one side of the frames.

Using my sheet of plate glass, graph paper and my 3/16in alignment rod to ensure everything was square, the frames were soldered together. They were just tacked together in a couple of places at first and checks were made with an engineer’s square to make sure that everything aligned correctly before going for it and soldering the whole shooting match together. After some work with the etched coupling and con rods that came with the kit, and comparing them with the borrowed loco, I decided to use milled coupling and connecting rods from Premier Components as they are nice and chunky. They were quickly supplied, in jointed form as requested.

Tapered end alignment axles were used in conjunction with these to fix into place the hornblocks. Some springs big enough to fit over the axles were utilised to help keep the hornblocks pressed against the insides of the frames. It was a bit of a fiddle to get everything in place for soldering, but it worked.

People have favourite Motor and gearbox combinations, mine are ABC so I phoned them up and they advised the best motor/gearbox combination for this particular engine. This was ordered and found to be entirely satisfactory.

I opted to use the Griffin (Ex Shedmaster) cast nickel-silver slidebars and crossheads in conjunction with the cylinder end covers from the same source. I wanted to make the whole motion bracket and cylinder assembly removable for maintenance and painting purposes, so some extra fabrication was required to attach the cylinders to the motion bracket as I didn’t want to rely on just the slidebars to hold it all together.

This was achieved by adding a plate to the middle part of the motion bracket to support some square brass tubing that conveniently fitted between the horizontal flanges of the cylinder castings. A plate made from some scrap etch beefed the assembly up. To securely mount the Griffin piston valve assemblies onto the cylinder blocks I used telescopic brass tube to link the front and rear. The Premier Components connecting rods needed a little trimming to fit inside the crossheads. The front and rear cylinder end covers were slightly too large a diameter for the DJH cylinder block. So I used my mini-drill as an improvised lathe to turn them down a little. This was achieved by drilling a hole in the plain front covers and mounting them on an 8BA bolt. The hole was filled with Milliput later. I find there is always some fettling to get slidebars into the right orientation and it’s probably best to ignore the motion bracket initially. The idea is to get the bars in the same plane as the cylinders and hopefully with the centre line aligning with the middle axle. The motion bracket can then be adjusted to fit. That is sort of what I did, well no, I started work on the motion bracket too early and ended up removing too much material from the slidebars. I had to do some remedial work; filling gaps with nickel silver offcuts, I rescued them.

The perennial problem with engines that have a driving wheel behind the slidebars is that there is a risk of conflict between the leading crankpin and the back of the crosshead. This seems to be the case in any scale I’ve worked in. My solution with this engine was to thin down the rear face of the crossheads as much as possible and on the crankpin, I used a reversed Slaters brass top hat bearing tapped to 10BA. I also filed down the rear of the leading boss on the coupling rods.

Some form of control is required for the trucks, so a nickel-silver wire projects from the middle of the frame stretchers to provide downward pressure and lateral control. The wire passes through a hole in a vertical plate soldered to the pony truck frame. There was a trial and error process to find the right size wire to do the job and it took a couple of attempts to get it right during the running in process.

Bodyshell

Detailing Work

Compared with the basic body construction, this always seems to take an inordinate amount of time and especially so on more modern locomotives that have their vital plumbing exposed to view. I try to start at one end and work to the other. In this case I continued with the remaining detail on the tops of the tanks. One thing missing from the kit are the distinctive support brackets and I used Griffin cast brass ones. They are all the same length, but on the prototype I suspect that they are longer where the boiler tapers in. So some filing and cutting took place to get them to fit, but the front one is a little too short, so they are not truly in line along the top of the tank, but at least they are there! One thing I found whilst trying to fit them was that the oval access plates on the tops of the tanks are too far back, so they had to be unsoldered and moved forward to allow the rear support to locate in the right place against the firebox. Maybe there were some minor variations between the different batches that were built.

Continuing the plumbing theme, I elected to use Griffin items for the distinctive lubricators on each side of the front running plate. I always seem to struggle when drilling lost wax castings with small drills (there are 8 holes on one side and 14 on the other) and now just accept that some will be sacrificed in the name of obsessive detailing. Early attempts at representing the multitude of oil feed pipes with tinned copper, and then straight brass wire failed dismally. A suggestion by a friend to use strands of soft brass wire from picture hanging wire did the trick. It can be unwound and straightened by clamping one end in the vice and pulling it with a stout pair of pliers. It is about 0.45mm diameter and does the job just fine, being soft enough to be manipulated into all of the bends without fracturing. The lubricators were fitted before the push-pull fittings. For these I used the DJH base and Griffin steam pipes and control valve fittings. They were soldered in place with low melt solder.

The other pipes and fittings were put in place around the smokebox and then the smokebox front could be put on. Finally the engine had a face. After completing the upper body work I added the steps as the body would be more delicate with these added. The etched items in the kit didn’t really do the job for me, so again Griffin cast items were used. They include a top stretcher which doesn’t exist on the prototype. To maintain the strength I filed these down to wafer thin from the inside face, and hopefully this isn’t seen from normal viewing angles. To add some strength I soldered some strip from the top step to represent the re-enforcement brackets. The cab steps are supported by the drain from the injectors. The injectors I used were Griffin ones of course. There were no mounting brackets available at the time, although Shedmaster used to do them, so I fabricated them from scrap. Rather than attach them to the chassis, I added a bracket from some brass strip to the underside of the body. This allows the body and all of the pipework associated with the injectors possible to be separated from the chassis as one unit. I used copper wire from electric cable for the pipe runs, it is easier to straighten and bend into place than brass. I also made up a representation of the rod from the brake cylinder and actuating crank, with a detachable pull rod to the brake gear. This has to pass through the triangular opening in the pony truck. Without the all the fittings under the cab, it would look a little empty.

The chimney, a Laurie Griffin brass one, and dome were added last, once the engine was sitting on its wheels and were glued on with epoxy. There are three different chimneys available for these engines and I had three goes at getting it right. Short, tall wide, and tall narrow, and it’s down to which engine and at what date as to which it has. The cab roof would be glued on later after painting and glazing the cab – not forgetting to put in the backhead and a crew. On examination, the backhead supplied in the kit appeared to be a BR Standard type with a pull-out regulator. At an O gauge show, I picked up a one piece casting (with a separate regulator handle, so it’s really two pieces) specifically for the Ivatt 2-6-2T. Painted and tucked way inside the enclosed cab it looks fine.

Testing, Painting and Finishing

A house move delayed the painting process, but at least that gave a convenient period for running in. So the Ivatt visited various friend’s railways. Inevitably there will be bits that drop off, short circuits to be resolved, and clearances to be checked

41280 was no exception, it was wired in reverse, a coupling rod joint failed (poor soldering by me ), the rear pony truck wheels wouldn’t rotate and a return crank unscrewed. The other problem I had was with the pony truck control wires. Various gauges of nickel-silver wire were tried out to get the right amount of control. The wire has to be strong enough to help guide the engine, but not so strong that it causes the flange of the wheel to ride up over the rail.

After a few running sessions the problems were ironed out. I build my trains with the intention of a six foot minimum radius curve, but the front pony truck wheels on this engine get very close to the steps at times. I also try and build my engines electrically ‘dead’ with the body and chassis not connected to either side of the motor connections to cut down on the risk of short circuits.

After the move I was fortunate enough to have a workshop to perform the spraying. It is useful to have a place where things can be set up and left out and also not to stink the house out with paint spray, which would incur the wrath of the domestic authorities.

Ventilation is a good idea and a mask is a must. Spraying outside on a still warm sunny day is preferable as the natural light is so much better than artificial and the paint seems to dry more quickly.

The first job is to dismantle and clean the model, I used a washed food container that had two compartments that I marked left and right to receive the respective motion, wheels and bearings in the hope that on reassembly the parts would all go back into their original places. This is an unnerving stage, taking apart a working model, but it has to be done. The body and chassis were then cleaned, I used a cream cleaner and an old toothbrush. This is where the quality of the soldering is checked and I’m pleased to say no parts dropped off. The washed body and chassis were then left in the airing cupboard to dry, having sole occupancy to reduce the dust risk overnight.

I used Halfords red oxide primer and satin black for the top coat. Once the primer was on and dry the model was checked for any areas that needed attention, holes to be filled or lumps to be scraped off. The top coat was sprayed on beginning with the underside first, and then the top side, leaving 10 minutes or so between coats. I always have some old boxes handy to test the spray first, I never spray the model without testing it on something else first, just to check the nature of the spray, and that it is the right colour. The model was then left for a week to dry thoroughly before embarking on the lining and numbering.

I elected to use Fox lining, as they do a specific set for this model. I found the best way to apply it is to cut it into small sections, starting with the corners and then join them up with the straight lengths. The red was added first and then the white/grey the next day. There was some variation of the actual positioning of the lining, so it is advisable to obtain a photo of the loco that the model is representing.

Numbers and insignia came from the HMRS set, although the numbers I used seemed a little large (8 inch), the next size down (6 inch) appeared too small. It took a week of evenings to complete this work together with a lot of concentration and patience to tease the lining into position using tweezers and a scalpel blade. It does curl and fold up on occasion, so a little water is necessary with a fine paintbrush to persuade it back into place. One panel per session is probably enough for anyone.

I used Precision Paints satin varnish to provide a protective layer applied with an airbrush. Once that had dried for a day or two, I painted the buffer beams; it’s easier when there are only two colours to worry about.

The chassis was sprayed with a weathering mix before re-assembly, other parts –cylinders, wheels and the like were painted by hand. At this point, the engine was re-assembled. No bits were left over and it still worked. I then cut out and glued in the cab window glazing with Evostick. I used a black permanent marker pen to run round the sides of the windows so that the edges don’t catch the light after they have been fitted inside the cab. When they were dry I cut some Tamiya low tack masking tape to cover the front and rear cab windows for the weathering stage. The side windows were left unmasked as they were invariably dirty. An overall blow over of my preferred mixture of Humbrol matt 33 black and matt 62 leather was applied.

Highlighted areas of rust and limescale were then picked out by dry brushing. The motion was given a wash over with a very thin weathering mix. Prototype photos rarely show shiny motion. I don’t think Annesley shed had many cleaners, and 41280 appeared to be pretty grubby from the photos I’ve seen, but I’ve been fairly restrained and you can still see the lining and insignia after all that concentrated work I put in to get it right. The backhead had been painted separately and was glued in last. I should have worked out a way of securing the cab roof before the model was painted. The last few details to add are the crew, fire irons (very visible on the fireman’s side tank top) and some coal.

The painting process sometimes seems to take forever. It’s useful to have other projects on the go at this point so that impatience to get the model finished doesn’t take over, it is worth the wait in the end.

Summary

Having had time to stare at the model, I think that the engine could be a millimetre or so short in the area of the cab entrance (although who knows, the drawing could be wrong or even my eyesight).

However it captures the look of the prototype, and is a charming model. Altogether, it was a most enjoyable build. The popularity of the model can be gauged from the fact that DJH offer this kit as a ready to run model.