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About this blog

Reports on my 2mm finescale modelling of the Highland Railway in the Edwardian era. I'm moving over from Blogspot (http://ayeates2mm.blogspot.com).

Entries in this blog

couplings

Experimenting with Lin-Cups

In my role as Publications Officer for the 2mm Scale Association, I'm currently working on a revamp of the "couplings" chapter of the erstwhile 2mm Handbook. I was intrigued by the reference to Lin-Cup couplings, which I hadn't heard of or seen. So I went back to the June 1976 issue of the 2mm Magazine to read Lindsey Little's original article. His goal of "something inconspicuous, not too unrailwaylike, close coupling, sturdy and capable of being made by a squint-eyed tyro with ten thumbs" soun
antyeates1983

antyeates1983 in couplings

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Scrap Tank - drawings

During the enforced shutdown I've started work on a loco to shunt my 2mm Diamond Jubilee Challenge entry: a Drummond 0-6-0T "scrap" tank, so called because they were put together by Lochgorm works from leftover bits of earlier engines. I decided to "borrow" the wheels and gears that were earmarked for a Barney 0-6-0. That loco will have an etched body and chassis, for which I have nearly finished the artwork. For a change, I decided that this one would be completely scratchbuilt.   My
antyeates1983

antyeates1983

3

Scrap Tank - new motor

It turns out that the cheap Chinese motors I bought on eBay are just that: cheap. Despite much fiddling with the motor position I couldn't get the original motor to turn the wheels while on the track. The chassis rolled freely with all of the gears and rods attached, but the motor would only turn the wheels if I held the chassis in mid-air, and then only if I held the motor in exactly the right place. On the track, it just wouldn't budge. Eventually I came to the conclusion that the motor just d
antyeates1983

antyeates1983

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scrap tank

Scrap Tank - painting

It's high time I posted an update on the scrap tank, which is approaching completion. Painting started with a coat of grey Halfords primer from a rattle can. I then used the airbrush to spray the basic green colour all over. I find that Tamiya acrylics spray quite nicely, so I used a mixture of olive green and white, thinned about 50:50 with Tamiya's own thinner. This works for me spraying at about 15 psi (although I don't really trust the gauge on my cheap and cheerful compressor). After painti
antyeates1983

antyeates1983 in scrap tank

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Scrap Tank - shaping the chassis

Having drilled the holes in the frames, I stuck on a template again and cut around it in time honoured fashion with a piercing saw:   Files were then used to finish the shape. As you can see, these include crude representations of the springs (just shadows behind the wheels, really). Shaping (and thinning) of the guard irons will be left until later. The extra material at either end was to facilitate clamping during the drilling operations but shouldn't be needed any longer.
antyeates1983

antyeates1983

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barney

Barney - design and etching

It's about time that I introduced my next locomotive project, which has actually been going on since before I started the Scrap Tank. It's a Barney 0-6-0. It started with the Worsley Works etch, but has morphed into a project using my own etches for the chassis and body, as well as for a 6-wheel tender (the Worsley etch provides the 8-wheel type). The main reason for not sticking with the Worsley etch was the fact that I wanted to do my own tender including axleboxes. I reasoned that I might as
antyeates1983

antyeates1983 in barney

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Scrap Tank - body shell

With the footplate ready I decided to press on with the basic body shell. First stage was to laminate two layers of 0.25mm nickel silver, again taken from the scrap surrounding an etched sheet. The pattern is stuck on with double-sided tape - I arranged the parts on the drawing to make use of one straight edge. The buffer beam is crossed out to remind me that I already made it!   Before cutting out the pieces I drilled the various holes using the Proxxon. Then it was a case of cu
antyeates1983

antyeates1983

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Scrap Tank - valve gear

This is the first time I've attempted outside motion, so apologies to the experts. I've concluded that it's rather small and fiddly, but no more so than other fine details.   First off, I drilled, sawed and filed up the connecting rods in the same way as the coupling rods, from two sheets of 15-thou nickel silver sweated together. Here you see them once the paper pattern has been removed. They're shape is supposed to be a simple approximation of the real thing. As you can see in this e
antyeates1983

antyeates1983

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scrap tank

Scrap Tank - plates and handrails

Here's a photo of the loco before the details referred to in the title were added. In this picture the motor is not fitted, so the cab looks empty. I was running it up and down the track under gravity after glueing the wheels into their muffs, checking that the motion was working. Actually I found that it was a bit tight and had to thin the slidebars further. The middle and rear crankpins have not yet been trimmed to length, so the temporary "washer" - made from electrical wire sleeving - grazes
antyeates1983

antyeates1983 in scrap tank

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Scrap Tank - coupling rods

Having drilled the rods (15 thou nickel silver) at an earlier stage, I then shaped them while still soldered together. For this I stuck on the template with double-sided tape, cut roughly to shape with the piercing saw, then began a reasonably laborious process of filing to shape. Always being very careful not to remove too much material! I find the most useful files for this are a triangular one (to get into sharp corners) and a flat one with one "blind" edge. I held them in the vice for doing
antyeates1983

antyeates1983

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barney

Barney - progress

Time for an update on this engine. I've been progressing this build in between other things so it has been quite gradual to develop. This first photo shows me milling out as much clearance for the coupling rods as physically possible. Part of the problem was that the phosphor-bronze footplate is quite thick and extends further down than the real footplate, so I removed the worst offending sections, identified by trial and error with the chassis. For future locos I suppose I will design in these
antyeates1983

antyeates1983 in barney

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Scrap Tank - drilling the frames

Construction began by preparing two lengths of 15 thou nickel-silver for the coupling rods and two pieces of 0.64mm brass for the frames. In the photo below you see the latter stuck together with double-sided tape.   It is critical to get the holes in the rods the same distance apart as the holes in the frames, so I temporarily soldered the two pieces of nickel-silver together and to one of the frames. (I didn't want to rely on two layers of double-sided tape). In this photo I scribed
antyeates1983

antyeates1983

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barney

Barney - details

I've gradually been adding the remaining smaller details, which seems to take up a lot of time. This first photo shows those at the front end. The lamp on top of the smokebox was included as a "fold-up" job on the etch (similar to a typical 2mm axlebox). The handle is rather delicate and hasn't survived the process of soldering it together, but I don't think you can see it well anyway. I will make the lens using PVA glue after painting. The smokebox door handles are made from etched handrail kno
antyeates1983

antyeates1983 in barney

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scrap tank

Scrap Tank - more details

Next I added some remaining details - the clack valves are impressions made by threading two short lengths of brass tube of 0.6mm and 0.8mm outside diameter onto a length of 0.4mm brass rod. All three of these came in a useful pack from Albion Alloys. They were covered in flux then soldered on with a small amount of solder, before bending the pipe to curve under the boiler.    Fiddlier to make were the next bits, which I **think** are controls for the sandboxes - they sit either
antyeates1983

antyeates1983 in scrap tank

0
barney

Barney - footplate and boiler/firebox

These photos show you the progress so far on the loco body. The footplate is made of two layers for strength, both etched: a top layer of 0.25mm nickel silver and a bottom layer of 0.4mm phosphor-bronze. To enable fitting of the buffer beams and side valances, the p/b layer is smaller, and the underside of the n/s layer has a half-etched rebate around the outside.     In this next photo you see the main etched parts fitted above the footplate, comprising the cab, smokebox fr
antyeates1983

antyeates1983 in barney

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barney

Barney - tender

Progress will initially appear exceedingly fast because I'm trying to catch up with this blog! But rest assured that I was doing this construction in about November over quite a few odd hours.   First up, here is the tender chassis assembled. The spacers are 6.4mm PCB with gaps filed in on each side, soldered on using the jig described in the previous post. The horizontal one is set slightly below the top of the frames so that there is somewhere for the solder to attach on top. The ext
antyeates1983

antyeates1983 in barney

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Scrap Tank - mounting the motor

Having said that the next post would be about the coupling rods, this will have to wait as I have been working instead on mounting the motor. I'm using a 7mm diameter coreless one from eBay, which has no built-in way of fixing it in place. So after some pondering I decided to make a collar that can be tightened around the motor to hold it. This started as a length of scrap 0.25mm nickel silver from the sprue of an etched kit. It was easily formed into a circle using a brass bar in the vice with
antyeates1983

antyeates1983

2

Scrap Tank - dome

I made a start on the boiler "furniture" by making the dome. The first problem I faced was not having an accurate drawing of the real thing. This led to me making a first attempt, looking at it sat on the model, and then doing another one with slightly altered dimensions. Although it took some extra time, this did also mean that I had a practice run to work out my method.   I started with some 8mm brass rod (annoyingly, the widest part of the flange was estimated to be a little more th
antyeates1983

antyeates1983

2

Scrap Tank - splashers

After a delay while I ordered some suitable brass tube, I've finally added the front splashers. I didn't fancy trying to bore these out of brass bar, and in any case didn't have any of large enough diameter. Instead, I had the idea of using brass tube. First step was to solder a sheet of 5 thou brass to the end.   This was then cut as close to the tube as possible with a Stanley knife. Then, it was chucked up in the lathe and turned down to the correct diameter, which was slightl
antyeates1983

antyeates1983

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barney

Barney - wheels etc.

The next thing I did was to add the reversing lever and smokebox door, which you can see in the photo below. The reversing lever was included (as a single piece) on the etch, but I struggled to fit it between the splasher and the boiler. I think this is probably because of the splasher being a bit over-sized compared to the prototype. In the end I had to file a curved bit out of the lever. The smokebox door was turned on the lathe, doing the curve with a graver. It has a spigot in the back locat
antyeates1983

antyeates1983 in barney

1

Scrap Tank - more details

I've continued to add some of the never-ending bits and pieces to my Scrap Tank, and it's about time I recorded the progress. Here are sandboxes (I think that's what they are but wait to be corrected) - filed up from spare chunks of brass with a hole drilled in and a little turned cap soldered in.   And here's one soldered in place next to the smokebox:   In front of and behind the sandboxes, the tops of the locomotive frames (on the real thing) are visible above
antyeates1983

antyeates1983

1

Scrap Tank - cab details

Hopefully I won't disappoint anyone if I reveal that I don't mean interior details. Rather, I've added the spectacle plates, beading and vertical handrails on the outside of the cab.   For the spectacles I made use of the etch I made previously for the Banking Tank. I already had a spare copy from which I had "borrowed" some other part during construction, so I thought I would make use of this. On the Banking Tank, the spectacles were part of half-etched overlays for the cab front and
antyeates1983

antyeates1983

1

Scrap Tank - gears and wheels

Here the gears and driven axle are in place in the chassis. The muff is reamed out to be a fairly loose push fit so that I can test the assembly. The wheels will eventually be glued in after painting etc. Some time was spent filing more metal off the chassis block so that nothing was catching. I've also countersunk the heads of the fixing screws here to make them as flush as possible to the side frames, not least because they will be behind the front and rear wheels. The crankpins had been glued
antyeates1983

antyeates1983

0

Scrap Tank - chimney

Apologies for the lack of updates recently. I've continued to make progress but not got around to writing it up. The next thing to be tackled was the chimney. Again I made a rough sketch guessing the dimensions from photos and Peter Tatlow's drawing. Since the chimney has a very thin skirt around the base, I decided to adopt the "squashing" method instead of the "filing" method used with the dome. In particular, I first drilled a hole up the middle of the chimney, then cut the top of the flange
antyeates1983

antyeates1983

1

Scrap Tank - safety valve

The photo below shows the safety valve "saddle", as well as the tank filler caps (which were straightforward turnings from brass rod). The saddle was made in the same way as the new dome, with a thin flange squashed on to a rod. I soldered a spigot up inside it, and used this to hold the assembly while drilling out the three holes on the Proxxon milling machine. The front hole is for the whistle.   The two main valves (not sure of the right terminology!) were made from 0.8mm bras
antyeates1983

antyeates1983

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