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Fairlie Merddin Emrys

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.

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 are my remaining work list and the paragraphs will be complemented as work progresses.

Smokebox doors

Brass castings need close inspection for imperfections. An easy way to spot these imperfections is giving them a quick spray of grey primer, that highlights any dimples, creases or other misfit. And it worked. I expected to find two holes but I found three more. After inspection I cleaned the castings with cellulose thinner, dried them and filled the holes with Milliput.

After 24 hours of hardening the Milliput could 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 modeling to shape the smokebox doors are once 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.

The doors were cleaned. Then the handwheels were glues in position, spindle down for the closed position.

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 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.

The smokebox fronts were soon suitably filled.
<<to be continued>>

Cab roof

As per [174] the roof has a small overhang (left). This is provided to ensure that the roof can be made exactly flush against the cab sheets (right). I should have done this in a much earlier stage but I forgot or postponed it for some reason. Anyway it turned up when checking the manual so I did it now. No harm done that I forgot, it only takes a little more care avoiding the pipes, but it is a delicate and careful job anyhow. It is also a job of inner peace and quiet, turn on some soft, nice music and go for it. It took me thirty minutes of filing for each side.

Spectacle plates

The spectacle plates are present twice 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 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 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 form one side until about half way
  • turn over the sheet and cut light gentle strokes form 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 us 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.

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

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.

 

Pry open the two halves with a sharp blade and insert the acrylic inset. See to it that it nicely falls into the recess, it should if you have worked carefully, and press the frame halves together. If the they do no come together the acrylic is at fault. Do not forces but rework the acrylic until a good fit is achieved.

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.

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)

Sand the front and back on 1200 waterproof emery. Be careful though to press on the frame only and not on the acrylic inset. Also take great care when removing the sanding residue with a soft brush to avoid scratching of the acrylic.

Open up the hole for the curved top latch.

 

The latches 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.

The result will approximately look like this

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

The lamp irons are not mentioned in the manual but can be found on the frets anyway. Determining the position of the top lamp iron was pretty easy: straight in the middle of the smokebox in front of the stack. Determining the location of the lamp irons on the apron proved to be harder then I thought at first sight. Both lamp irons are on the driver's side, so much is clear. To determine the exact position I needed two views. And again my irrepressible urge to make photo's without end paid off.

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

and second I found a head on photo in my own collection which was one of a series of eight or so which I made in 2011 when Merddin Emrys pulled into Tan-y-Blwch in most dreadful weather, hence the poor quality of the detail shot.

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 special comments. Note that the top lamp iron's base is curved to follow the smokebox shape

Handrails

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 not is that I used a tapered stirring stick on which I pressed on pretty hard. So 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.

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 is not 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

Rework cylinder cocks

Motors

Name and works plates