7.6 Completion

My build of Merddin Emrys is drawing to a close. I have drawn up a list of chores that remain to be done to finish the actual construction before the painting process. A surprisingly short list I may say. This list was made by

• digging in my memory which chores were still on my mind;
• rereading the manuals of the power bogies and the superstructure and isolating instructions I had overlooked or postponed;
• assessing the parts remaining in the box.

As to the latter: I could account for most of the remaining parts as spares added in the frets or left overs from version choices. A few however were more mysterious and these were the subjects of a last bout of questions to EDM Models. None of these however proved to be a serious omission.

The paragraph headers on this page were on my remaining work list and the paragraphs were complemented as work progressed.

Smokebox doors

After 24 hours of hardening the Milliput could be worked on. Scraping, filing, sanding were unleashed to remove superfluous Milliput. Remember that any amount too much Milliput results in much rework yet any amount too small is punished by another filling and 24 hours' wait. A devilish balance!

After modelling to shape the smokebox doors are once more sprayed with primer to trace any imperfections.

The right hand one is still not right at the centre boss.

After a second round of smoothing it however is.

At a first attempt to glue the doors, much to my horror I found that the door had a substantial play up and down and left and right in the provided opening. This way the door could not be centred correctly.

I also realised that I left two holes open in which the door hinges would have fit in an earlier version of the kit, before the hinges were cast integrally in the smokebox door. So I will have to do some filling and filing to close the two holes.

I measured the opening in the smokebox front (15.0 mm) and the size of the inner ring at back of the casting (13.8 mm). Having 1,2 mm play is simply too much. I cut small shims from 0.5 mm styrene sheet and glued them on the edge of the inner ring. The door would now fit with negligible play.

Note: two shims on the left door are at fault, one is completely missing and the other came away. Before fitting the door again I corrected that.

I mounted both smokeboxes on a straight strip of wood. This would make it

• easier to handle the smokeboxes;
• easier to measure if the smokebox doors would sit absolutely level during glueing;
• possible to lean the smokeboxes back after gluing so the doors would not fall out when the epoxy glue hadn't set yet.

To the latter the manual puts rightly so [226] "take a good look to ensure it is correct, or you will always notice it!"

Done!

Cab roof

Spectacle plates

As the manual hardly goes into detail on how to make these spectacle plates I will elaborate on the subject.

There are two sets of spectacle plates present in the frets: in nickel silver on the standard fret of the superstructure and in brass in the separate fret with the name and works plates. I considered the nickel silver versions superfluous as the final spectacle plate will be from brass. So I used them to make a trial version. Never waste an opportunity to practise before you jump.

The manual states that the spectacle plates are designed to take up 10 thou acrylic sheet, 0.25 mm. I had only 20 thou / 0.5 mm but it fit well in the nickel silver version, so I wondered why the manual would state otherwise. I was a bit suspicious about that as the manual is always right (rule #1). I also found the nickel silver result overly thick with 1.1 mm overall thickness. Then it dawned on me that the brass sheet might be thinner. I measured and yes it was! The brass version is only 0.3 mm thickness and allowing for some tolerance it will only take up 10 thou sheet. Better, but I must obtain that first.

Nevertheless making the nickel silver version taught me some invaluable lessons.

• first and most important it helped me getting the swing, "how to" without the risk of wasting one of the four brass frames;
• be careful when bending over the two halves, it is easy to distort the frames;
• be extremely gentle with the clear sheets, it easily scratches, spoiling the whole result;
• yes soldering can be done with the soldering iron at 200C and using 140C solder and the least amount of lingering with iron. It is nerve wrecking to solder to close to plastic. If the prospect scares you read my afterthought, which gives you a way ahead without soldering.

The second attempt already showed a marked improvement, now with 10 thou clear sheet which I was able to obtain at short notice at my local hobby shop, 't Oude Station (the Old Station).

Again I learned a valuable lesson. Do not try cut the clear sheet in one big cut despite being only 0.25 thick. It will result in creasing and tearing however slight.

• get a fresh sharp blade out
• cut in light gentle strokes from one side until about half way
• turn over the sheet and cut light gentle strokes from the other side until de sheet gives way

That way you will have absolutely clean edge.

A few other tips

• Use a sheet of new and clean paper as underlay. If you work directly on your cutting mat stray brass and nickel silver shrapnel will scratch your sheet.
• If you use a steel ruler to cut, put another sheet of paper between the sheet and the ruler so the ruler does not scratch the sheet either.
• Handle the acrylic sheet with the greatest care as it is very vulnerable to minor scratching. Even rubbing with you fingers causes minute but visible scratches.

First the etches are cut out of the fret. Be gentle as the material is very thin. Use a sharp blade on a hard underground. Cut as close to the frames as you can.

Do not try to remove the etch cusps and the remains of the tabs at this stage. The frames are too vulnerable and you will have to file the frames after soldering anyway.

Measure the width of the frames on the inside of the recess and cut a strip of sufficient length and of the appropriate width from 10 thou (0.25mm) clear sheet. I did not measure in absolute mm's but used my recently acquired Haff dividers to transfer the measures. Much easier and more accurate.

The curve of the upper end of the window has its centre on the bottom of the frame so you can easily use the dividers to draw it on the sheet. Trial fit and work the acrylic until it happily falls into the recess.

Once the acrylic fits, fold the two halves together so that they sit absolutely flush on top of each other. Carefully align all sides to match each other.

Pinch the connecting tabs together but do not completely fold them together for two reasons:

• you still need to open up the frame to enter the acrylic inset;
• if you pinch it completely the frame will tend to open on the top making achieving a good fit more difficult.

Like so.

Now comes the tricky part: soldering brass while having the vulnerable plastic inside! I used 140C solder and set the soldering iron to 220C (a tad higher than with the nickel silver trial as brass needs a bit more punch). With this temperature the acrylic will melt. So how to now that the brass is not getting too hot? Well, hold it between your fingers like on the photo while soldering. As long as you can hold the frame between your fingers, the brass is not too hot! Flux well, use tiny amounts of solder and only short and quick passes of the iron. That will do the trick.

Directly after soldering

and then after filing and sanding.

Then file and sand the frame until the brass side shows up again. Remember that you did not remove the cusps and tabs? Well while working on the frame now you can take the cusps and tabs away as well. Now is also the time to pinch the bottom tabs together completely (visible on the next photo)

Open up the hole for the curved top latch.

The latches are made by winding a 0.3 mm nickel silver wire around a "rod" of 10 mm diameter (I used a felt pen). The springiness of the nickel silver will make it into a circle of about 17-18mm. Cut a full circle in four quarters.

Nail the spectacle plate down on the soldering pad and insert the latch pushing it partially into the pad. This way you have your hands free for a last quick solder.

Then cut the part of the latch that stuck into the soldering pad, file and sand smooth. Done!

Final adjustment of the tabs and latches will be done when the spectacle plates are mounted after painting. For now they are carefully stored in a separate box until they are needed during final assembly.

Afterthought

When writing this paragraph I mused on the photo above and on the still relative thickness of the result. I suddenly realised I could have taken another road.

• Buy even thinner acrylic, it is available in 0.005"/ 0.13mm.
• Cut the windows as described and keep them in a safe place.
• Use only one half window frame (so cut the connecting tabs halfway).
• File and sand this half to remove the tabs and etch cusps, be extremely cautious though.
• Solder the latch as described. Ensure the latch goes to the side of the recess. The recess will be the inside of the spectacle plate, facing the cab, as it then will be least visible.
• Then finally glue the acrylic in place with a minimum amount of MicroScale Kristal Klear in the recess

This way you end up with spectacle plates only half the thickness and you will avoid soldering near the acrylic. You also have four frames a spares. In hindsight I might have chosen this road because the result will be much thinner. But what's done is done.

Lamp irons

Top side ©2011

Bottom side  ©2011

First I found a broadside view almost straight on the lamp iron. Photo from the manual DVD used with kind permission of Paul Martin ©2013 EDM Models

The conclusion from the photos was

• in the longitudinal direction of the loco the lamp iron was pretty much in the middle of the smokebox;
• in the lateral direction it was a bit off centre relative to the sandpots towards the edge of the apron.

That being said, I could complete this chore.

The readied lamp irons. 1x1 cm squares demonstrate their tinyness.

Soldered in position

Work is easy and demands no other special comments than that the top lamp iron's base is curved to follow the smokebox shape

Handrails

A shot from ME in 2017

Next to each cab side sheet there is a blank metal hand rail. On top is a flat piece of sheet metal to keep in place.

[180-183] The manual recommends to bend 0.5 mm nickel silver wire and solder it into the provided etches recess in the back of the cab side sheet.

This would result in a curves angle and the top metal would not be flat. I tried to mimic the flat top by first flattening the nickel silver wire in a pair of pliers and then bending it over as sharply as possible.

The cab sides are put into place with a dot of Blu-tack and the handrails is likewise added. Then the top is soldered.

The sides are kept removable to accommodate the painting of the cab interior, so they are stored in a safe place.

Sandpots

Not much to be said about the sandpots. They need errrm sanding (!), after being filed flush. The only thing of note is that I used a tapered stirring stick on which I pressed the sandpot pretty hard. This way I could on them easily.

Again they are not installed, but kept separate until after the painting process as they are very much in the way of the airbrush.

But what after the locomotive and the sandpots have been painted? Two problems arise.

• First the sandpots will be glued on the painted surface. Painted surfaces are generally not the best places to glue to. The bond between the paint and the metal is not overly strong. That means if you knock the sandpot incidentally it will come away tearing a big hole in your paint in the process.
• Second during glueing it will be infinitely difficult to position the sandpots exactly spot on without smearing the glue all over the place.

So out came the saw table and I sawed four pieces of brass pipe of just a few tenths of a mm under the width of the inside of the sandpots.

Safety valves

The safety valves are glued with 5 min epoxy as they very difficult to get to with a soldering iron. They are set so the the lever points towards the stack but that does not need to be necessarily so. I have lots of photos where they point in any direction. I just found it neat to arrange them forward..

Like the sandpots the domes are not installed, but kept separate until after the painting process as they are very much in the way of the airbrush.

Adding weight

First I added lead on the firemen's side where the coals chute is in the way. I made strips of 40, 35, 30, 25 and 20 mm to fit under the chute once piled. The black mark indicates the top front side of each sheet, to enable easy working.

On top of the first five layers I made a pile of five layers of equal size to fit in front of the shut. I took care to provide a gap for the bolt that will secure the bogie to the frame (circle)

Piled up it looks like this

Before long I had four identical sets

Lead filler for the bottom of the firebox. It is split in two halves so I can feed it through the front and rear openings of the firebox. If I had kept the ash pans removable (as designed) I would not have needed to do so because I could have accessed the firebox from below. Well, that's life.

I also made two coils to fill the smokeboxes. Again do not be tempted to fill the entire boiler front. If you want to fit the motor with a flywheel you will need that space!

The original loco body weighs 186 gram.

110 gram in the tanks

42 grams in the fireboxes

and 95 gram in the firebox

The whole lot together.

I glued the five lower weights for the driver's side tank together before inserting them in the tank and inserted them in one piece in the tank. I did the same with the five small top pieces. On the firemen's side I inserted the five lower strips one by one because the coal shut. made it impossible to insert more than one at a time.

Everything was glued with epoxy.

Total weight 429 grams, so I lost 4 grams on the way because I had to make some alterations to make everything fit. Nevertheless I more than doubled the weight of the loco.

Name and works plates

I could postpone the work on the name and works plates until after the painting. But vanity demands that I put name and works plates on the locomotive for the recording of the finished but unpainted locomotive as I always do. On the other hand I can not take the plates out of the fret unpainted because painting them afterwards is difficult. So I will now paint them, attach them temporarily, use them for the photo session of the completed locomotive, remove them and then store them until the painting process has been completed. O vanity of vanities...

To obtain a black lettering the name and works plates were sprayed, first in a base coat and than black. The result was left to set fully for 24 hours.

After that the plates are carefully sanded with 400 grit paper until the letters show up correctly and remaining paint is gone. Then the plates are sanded smooth with 800 and 1200 grit paper.

The works plate are to be fit on the round smokebox. Although small the plates are big enough to who small gaps on either side.

Some corrections are needed but the result is satisfying.

Rework cylinder cocks

The manual clearly warns to check if the cylinder cocks clear the rail. Instruction [197] says "The steam operated types (for Merddin) need to be fitted carefully to ensure they are not lower than the wheel treads, otherwise they will foul pointwork."

I did not heed that advise and found that out much later.

The photo needs no explanation

The idea was to file the cocks skew.

Soon the cylinder blocks were freed of their too low hanging fruit.

Apart from skewing the spigot also needed filing round.

Soldered back in place.

The drain pipes were also bent a little closer to the valve body and now the cocks clear the rail well enough.

Motors

The motors are finally wired up ensuring that each unit runs in the right direction when applying current. Then the units are interconnected which two extra wires that will run through the firebox. For disassembly a pin and plug connection is added.

This electrical interconnection of the bogies results in superior behaviour of the loco on less than favourable track. One bogie will feed the other if it looses contact, avoiding any hick-ups, where the loco would have two hick-ups, one time for each bogie, when it passes a currentless spot.

Then follows a test run of the wired bogies

Top without flywheel, a bogie runs just short of 15 cm to come to a stop.
Bottom with a flywheeel it needs 27 cm,almost doubling the distance.

But don't forget this only applies when running at full speed. So no, I don't it will make much difference

Done

Now the locomotive is down to four major components

• the main body
• the two bogies
• the roof

and seven sets of small parts, to be added after painting

• four spectacle plates
• four cab side sheets
• seven name and works plates
• two domes
• four sandpots
• four straight handrails for the tanks and two formed handrails for the smokeboxes
• a few meters for the cab

Assembly is dead easy and completes the build of the wonderful kit.