Tender sub-frame complete except for the water pick-up scoop
The tender sides and ends in place. The beading, grab rail and handrail stanchions were fitted earlier. The tender top and coal space were dry fitted using the tender front bulkhead to ensure everything was in the right place before finally soldering the top to the sides and end.
My adaptation of the tender front to represent the earlier type of tender

I like to build the tender of tender locos first, mainly because when you finish the loco it's already there and it really seems like the model is complete. The tender parts and loco parts in this kit are mixed between etched sheets which makes it difficult for those who want to make variations on tender type. As with all etched components I always try to file the etch cusps off the edges so that they fit better and look more professional. I started with the tender sub-frame, making sure it was square and the axle holes were reamed out to make a free running model. I made the centre axle holes a bit looser and gently filed them top and bottom to ensure the wheels stayed on the track and didn’t stop turning.

On the tender body, I deviated from the recommended sequence of construction in the instructions because I like to assemble a tender from the footplate down followed by the body. So I cut out and fettled the footplate and fitted the drag beam and buffer beam. Because fitting the steps with the tender frames in place is annoying and tricky, I fitted the steps, soldering from the inside while they are easily accessible and, while I was at it, I fitted the step treads. If there had been a valance I would have fitted that before the steps. I then soldered the outside frames from the inside.

With the underframe completed I moved on to the tender body. Before assembly I soldered on the beading strips, fitted the handrail knobs and grab handles while the side was flat and the inside could be accessed, and cleaned up before assembly. The same goes for some of the tender rear detail. Next the sides and ends were soldered to the footplate. I first tack-soldered the parts using small blobs of solder, making sure that the sides are vertical at the front. The tender top and coal hopper are quite complex shapes and the instructions mention that some adaptation is needed to get the shape right. I checked that the front of the hopper was in the right place to allow the tender front bulkhead to be located correctly, by doing some dry fitting.

The kit provides a standard LMS 3500-gallon tender but even these varied. Many had coal rails added later in life and these are provided in the kit. Later examples had an access hatch in the front of the tender so that the fireman could get into the bunker to push coal forward without having to climb over the top of the bulkhead. The kit provides for these doors but I wanted to model one of the earlier tenders that had tool boxes on a flat platform at the back of the footplate area. I mainly used the existing parts in the kit which were adapted as required but some plain rectangles of brass were cut out to make the alterations.

With the basic body assembled it was time to fit the beading along the top and ends. These are provided in the kit and just need a bit of time and care. Make them a tight fit and work along from one point. Never try to tack each end and solder between or they will bend and distort because they need room to expand with the heat.

Generally I start with the chassis and get it to a state where it can run but is not cluttered with details that make adjustments difficult. The first thing I usually do is assemble the coupling rods, which on this kit are designed to pivot in two halves around the centre crank pin. I always adapt them to pivot at the joint behind the centre pin which ensures that the rods maintain their accurate length even if the crank pin holes are opened out a little. I next test-assembled the frames and spacers with the motor and worked out where the pick-ups would go. Usually I use the PSF plunger pick-ups supplied by Geoff Stratford because they are adjustable and accessible. On the 4F I had to miss out some of the frame spacers because I used an ABC motor/gearbox driving the centre axle which is different to the design of the kit.

The frames and spacers were then soldered together ensuring all was square which was not difficult on a kit as accurate as this.

A quick test assembly with the wheels proved that the kit made an accurate free running chassis without any compensation, though I think some element of compensation ensures better electrical contact through all the wheels where there's unevenness in the track.

I made the front axle pivot around a steel rod located on the centre line of the chassis. The middle axle is lightly sprung and the rear axle is rigid. Once the pivot rod has been soldered into pre-drilled holes in the spacers, located using the original axle holes to position an axle, I removed the bearings and carefully filed the axle holes in the frames in a vertical direction only. Then using some extended axles that fit into the bearing holes in the coupling rods I located the main bearings and fixed them using lengths of 0.7mm wire soldered to the frames at one end and onto the bearings at the other. This enables the bearings to move up and down so that the front axle can pivot round the beam and the centre axle is able to move up and down but is lightly sprung by the location wire.

Once the bearings were located I test-fitted the wheels, motor and rods and checked that everything ran smoothly. I often have to open out the bearings in the rods a little to make everything free. Finally I fitted the pick-ups, wired up everything and tested the chassis under power from the track. At this point I moved on to building the loco body knowing that everything was running freely and so I could deal with any clearance problems if they occurred.

I have set out the main parts of the loco chassis to plan the layout and location of major components. The small rectangles on the inside of the frames are PSF plunger pick-up bases. The frame-spacer at the top of the picture could not be used as intended in the kit but can be adapted to add strength to the chassis if required later.
The basic chassis after assembly. There is part of the missing spacer flat across the top and another behind where the motor fits. I have fitted a compensation beam above the front axle, and the front and middle bearings are able to move up and down but are controlled by wires soldered to the frames and the top of the bearings.

The buffer beam, drag beam and valances are soldered in place. What is not in the photo is the wooden platform that I cut to support the body during construction as the footplate is easily distorted. The cab after attaching the beading and grab rails.

It is said that 'the devil is in the detail' so with this model I made 'the devil take the hindmost' and tried to get all the main parts to go together before I added vulnerable detail. That is not strictly true because on all models there are some details that are much less of a devil if fitted early on, but the bulk of the detail is best left until the big bits are done and all the rough filing and cutting is over while there is a lot less to damage during the combat stage. The 4F is a fairly simple loco to build but has a few pieces that require curves and bends, which always offer scope for error. The best advice is to take your time. As always, I started with the footplate and generally followed the instructions. I always make a platform on which to sit the footplate so that I can keep an eye on how level and straight it is. In the case of a simple flat footplate loco all it requires is a suitable block of wood cut to fit inside the valances and buffer beams. Once I had got the footplate with valances, buffer beam and drag beam assembled I fitted the cab according to the instructions.

On the cab I added the cab beading and the cab cutout beading, also the front spectacle frames and the grab rail prior to assembly on the footplate. The cab roof, which is a wrap-over design, comprises a large white metal casting that has to be a seamless fit to the top of the cab sides. I dealt with this at the same time as the cab was fitted to the footplate. Then I spent some time bending, filing and fiddling with it until it was a pretty good dry fit on the cab. I then put it aside until later as, being white metal, I was apprehensive that it might suffer collateral damage during subsequent soldering work.

At each stage I test-fitted the emerging loco with the chassis and tried to deal with and anticipate any places where the wheels or motor would come into contact with the body.

The next big bit was the boiler, smokebox and firebox assembly. The firebox, being a Belpaire design, requires two reasonably tight curves at the top. I used the etched front and back to locate these and formed the bends using a mixture of formers and brass rods. My pleasure was negatively intensified when I made a small mark to indicate the start of the curve and promptly formed the curve on the wrong side of it! The devil took time off the detail and instead fed words through my mouth that my gran would not believe, had she still been alive. However, one thing about curves is that they are not too difficult to move and the damage was eventually overcome with no ill effect on the model – unlike to me!

The boiler is pre-formed and presented few problems. The smokebox required the wrapper to be formed and tightly fitted to the front and back bulkheads, followed by a detailed overlay wrapper. Really this is a matter of patience and persistence. The whole unit was first tack soldered together then, when I was happy, I carefully seamed the ends in place. I formed and tack soldered the wrapper but used a blow torch carefully applied to tightly solder it in place. I used a length of brass tube to locate the boiler accurately to the smokebox by opening up the holes in the bulkheads of the smoke box and boiler to enable the rod to be a close sliding fit into them, thus locating them, and then seaming round the join from outside.
There is a radius between the rear of the smokebox and the boiler. I used a length of thin copper wire pushed tightly into the join and flooded with 145 degree solder to give the impression of a curve. At all stages of this process I used glass fibre brushes to clean up surplus solder and make everything tidy, then spent a number of days making sudden squeals and yelps as the bits of glass fibre made stabs on and between my fingers!

Here are the results of pre-forming the smokebox wrappers and firebox
A brass rod fitted through the holes etched into the smokebox and boiler bulkheads locates the smokebox to the boiler accurately. Mark the top of the two units so they line up along the top and are not twisted

There are three outstanding areas of detail to add once the basic chassis is running. They are the inside motion, the brake gear and the sanding gear. I started with the inside motion because that is inside the frames and I didn’t want to damage the outside bits while fitting the bits between the frames. The kit provides some parts for the reversing cross shaft and levers with counterweights that fit behind the motion bracket, but nothing to go in front of it. In the Wild Swan LMS Locos book there are drawings of the arrangement of the slide bars and valve gear links. A distinctive feature of the valve gear is that it is located above the slide bars and activated by rocking levers fitted on the motion bracket. I only modelled the top bit of the motion and used an assortment of shapes from my scrap box store to represent the various levers, slide bars and rods. It’s just a muddle-up but, when the body is fitted, it looks a lot better than an empty gap, especially when it is made a bit mucky and oily looking. You can of course really go to town on it all but leave me at home in front of the fire with a beer.

The brake gear was assembled as per the kit. Remember as always with brake hangers and shoes that they are handed, so three of each. The sanding gear in the instructions consist of plain wire 'pipes' but 4F’s had steam sanders and a bit of extra work makes a lot of difference to the atmosphere of the model. I fitted the sandboxes which are white metal castings and bent the wire sand pipes as in the instructions. But then I reamed out a 14BA nut and soldered it about three millimetres from the end of the wire and at the same time soldered a length of 0.5mm wire to the underside of the main pipe just behind the nut to represent the steam pipes. I copied the photos and drawings in the Wild Swan book and bent the thin wire to vanish behind the frames and soldered them there.

I then considered the chassis complete and after a scrub gave it a coat of black paint and the motion in red. I always try to weather and muck up the frames before I fit the wheels back on. After fitting the wheels I weather any other bits that need to look oily, mucky or rusty when the whole thing is together after a final testing under the loco body. I must say a grubby chassis under a shiny unpainted body looks really odd but it's easier that way.

My representation of the top part of the inside motion.
Sand pipes with additional steam pipes fitted

Here are the results of preforming the smokebox wrappers and firebox

This is the 'home run' part of the build but can take a considerable time despite the apparent simplicity of the 4F. First, I fitted the cab roof so as to complete the main parts and strengthen the cab unit. As I mentioned earlier, I had already got the roof to be a good fit and so all I had to do was fix it. I used tack solder blobs of 145 degree solder quickly applied on the inside of the front and sides, to fix the roof securely in place. The large roof is reasonably tolerant of heat but don’t touch it directly with the soldering iron and let the solder flow from the etched cab front and sides. I then used a temperature-controlled soldering iron to put a good fillet of 70 degree low melt solder along the outside of the side joins, which have to be invisible. If you are modelling the engines later than the mid-1930s you have an easier job because the LMS fitted a rain strip where the white metal roof is fitted thus hiding the join a bit. But for earlier models the join has to be filed and abraded so as to be invisible. Again, just be patient.

Before sending the model to the paint shop, I assembled the loco and tested it. I use a simple toy-like system to join the loco to the tender by a crude 2mm diameter rod soldered to the tender front draw beam and an L shaped plate soldered behind the loco drag beam, projecting out under the tender and drilled for the tender pin. To ensure the loco has enough clearance relative to the tender to enable it to go around the rather fierce 5ft radius curves on my layout, I used the following method. I put the loco and tender on a length of 5ft radius curve with the inside corners about 1mm apart. Using dividers, I measured the distance between the two, in the middle of the footplates. I then drilled the hole in the L-shaped draw plate so that the rod on the tender fitted at just the right distance from the loco to enable them to freely negotiate the 5ft curve. As the tender is dropped onto the plate behind the loco, I solder the loco fall plate to the tender, not the loco. I just love cheating!

My way of linking engine and tender