June 2019 meeting

Jim, Alistair, Stephen, Andy, Gordon, Simon and Graham met at Alisdair's house in sunny Scotstoun for this month's meeting. The Short Talk was by Alisdair himself, on a subject close to his heart as a retired civil engineer: Bridges, and typical features to include when modelling them. He recommended "Bridges for Modellers", L.V. Wood, as a good reference (originally by OPC, reprinted more recently in paperback: check out the usual Internet sites to find a copy).

The talk was illustrated with photos of railway bridges in the Glasgow area. We were shown how iron and steel girder bridges often have a "hog-backed" shape seen from the side, rising from each end to the middle, with characteristic vertical stiffeners to the side of each flanged girder. Among other functions, these stop the girder failing by buckling downwards or outwards. The stiffeners are often wider at the top, and their spacing varies: a long span will have closer stiffeners. Under the bridge, cross-beams in line with the stiffeners prevent shear forces tearing the bridge apart, and in older bridges are often revealed by rivet patterns on the side girders. Steel troughs between the cross-beams allow the track to be ballasted across the bridge; the troughs are often lighter weight when a load such as platforms rather than track is carried. There will be pilasters at the end of the bridge, which provide a structural function on arches but also a practical and aesthetic function on other bridge designs.

We were shown a variety of photos of skew bridges and Alisdair explained the various additional forces these introduce, often in counter-intuitive directions, and the design features required in consequence. We saw examples of bridges replaced during their working lives and the difference this can make to the abutments, for example ashlar masonry being replaced by brick or concrete; and how concrete retaining walls are often given horizontal courses to conceal the cracking which occurs normally - the concrete cracks unobtrusively at the course rather than in full view.

Detailed photos were produced of bridge beams resting on padstones at each abutment: stone padstones on older bridges, concrete in modern. Arch bridges were explained as being basically of circular, elliptical or segmented shapes, with the segmented type in particular requiring substantial amounts of rubble behind the abutments to stop the ends of the arch kicking out. Circular arches are much less demanding. The arches also rest on padstones, with skewbacks (I think) to spread the load outwards. Seen from below, the arch stones typically fit very tightly together, since if they are loose they will move and rub when loaded, and soon fail.

Other stresses try to tear the arch apart sideways, and if this starts cracks, patresses (steel plates) are often applied to each side of the arch connected by rods passing right through the structure to resist these forces. There was much more explanation and many illustrative photographs showing how the various design features were expressed by engineers in the distant and more recent past. The speaker's expert knowledge of these features did not stop the audience from contributing their own views, but Alisdair showed commendable restraint and so we were all satisfied. A most interesting talk which hopefully will lead to more accurate bridges on our layouts. We had no idea Alisdair's professional life had been dominated thus by stress, but it does explain some of his own more unusual design features which have puzzled us in the past.

Simon had some interesting boat kits in card and paper for a Clyde puffer and a small fishing boat from ScaleScenes. These look to be nicely designed as waterline or full-hull versions with excellent instructions. Simon also had questions for us regarding point construction with the Laurie Adams chairplates, which he finds either too tight or too lose to grip the rail. Discussion ensued without conclusions: advice will be sought from the designer.

Jim had his latest footbridge etches for Dunallander for our inspection, and very nice they looked too. He's awaiting arrival of the turned support pillars.

The stair treads are folded up from a single piece of etch, but Jim soldered a flattened fine wire on each one to provide a lip to the steps: the slight relief catches the eye and improves the appearance considerably. The T-section girders of the side supports and hooped entrance arch are surprisingly strong, in spite of being from 10-thou material for the stem of the "T" and 5 thou for the top. The design and build is documented in Jim's RMWeb thread here.

Jim also had his venerable 498 class Caley dock tank for inspection so we could see the recently-fitted pickup skates in action. The photos deliberately use a light background for illustration: in practice on the layout they are not visible.

If you look closely you can also see the coil springs in the Alex Jackson couplings.

Jim found it was necessary to shape the support wires for the phosphor-bronze skates carefully, so they do not catch on point crossings.

And indeed the "beetle-crusher" did seem to run better.


Alisdair had his erstwhile test plank on display, which has now blossomed into "Aye", a mini-layout based on an imaginary Highland Railway station. (There is bound to be some horrible pun involving the title, so far not revealed to us, and for all I know the spelling is less obvious, in the same way that the village of Avoch - from the Scots gaelic Abhach, "mouth of the stream" - on the Black Isle is pronounced "Och"). The station building, based on Grandtully, was featured in last month's blog.

A detail of how the boards are joined using flight-case over-centre clips:

and the spring-loaded sector plate stop:

and a view from underneath:

 
A fault-finding session ensued: a slight kink in the track, hard to spot without assembling the full layout, was the cause of persistent derailments of longer-wheelbase locos. A faulty DPDT switch was also replaced. We will no doubt return to "Aye" in future blogs.

The big news at piece-time was the replacement of bacon, with its attendant smell and mess, by roast ham with cream cheese and tomato in the rolls. Domestic harmony was thus assured and it has to be said that the rolls were fully better than the previous version. A wide variety of fresh baking was also provided. The East Coast elements of the FCAG will have to look to their culinary laurels. This is, of course, all a distraction from serious modelling, but we are easily led astray.

Some discipline was eventually restored and a peaceful scene ensued in the afternoon sunlight: Jim working on preparing the etches (of his own device) for his new loco, which will be a Caley 323 class "Jubilee Tank"; Stephen soldering up the axleboxes he'd spent his dinner money on at Tutbury; Alistair adding a loco servicing road to his Edinburgh layout pipe-dream; Andy browsing the latest magazines; Graham soldering up yet another 2mmSA LNE fishvan chassis; and Alisdair brewing coffee and tea. His flowery pinny is on order.

 
And so the afternoon drew to a close. Our next meeting is proposed to be in Edinburgh, exceptionally on the first Saturday of the month, July 6th.

June 2019: 2mmSA Expo, Tutbury

Three FCAG members - Stephen, Alisdair and Graham - made the trip south to Tutbury in the English Midlands to sample the delights of the 2mmSA Expo. The trip was well worthwhile and there was plenty inspiration on display. Here are a few random snaps.

Bryn Davies' Colwyn Bay Goods: a Clayton seems to have escaped to Wales ... but to be fair most of the shunting was with more conventional motive power.

Angus Higgins' Glencruitten. I haven't captured the colours very well - the contrast of the sky, grass, and camouflaged hangar is striking, and very satisfying.

Ian Smeeton's Paisley St. James: a web of steel (or rather, nickel-silver)

The Kent and Essex Area Group's Lighterman's Yard, impressive as always.

Pete Matcham's Kyle of Lochalsh: I think this is the first time I've seen it "in the flesh". I managed to catch it when there were no trains, just as the prototype usually appears:

and his new concept display for Meeth:

I forgot to capture the other concept display for Loch Awe. Everything executed with great style and precision.

Anthony Yeates' Corrieshalloch, which gets better every time I see it. A Peter Drummond Banking Tank (oops - I missed a photo), and a variety of coaching stock including a Jones coupé-ended coach and an HR brake van, all from Anthony's own etches, were on display.

Steve Nichols' Parkend. A lovely layout which also ran beautifully.

There were demos a-plenty: Andy Carlson's Arduino-controlled shunting tractor and concept for Hayle North Quay:

Keith Armes' track-building: Keith was also showing a small layout:

David Eveleigh's coach-painting:

Nick Mitchell's stay-alive DCC:

Edward Sissling's wheel-turning:

and trade support from Nick Tilston's N Brass

and Allen Doherty's Worsley Works. Allen showed me how to use inexpensive garden secateurs - Kent and Stowe 6mm pruning shears, available on eBay for less than £10 - as metal shears to cut sheet brass to precise size without distortion. The trick is to cut only with the part of the shears from the pivot to half-way along the blades, then move the blades for the next cut, rather than cutting right to the end of the blades; and to take a rough cut wide of your scribed guide line which will leave a twisted edge before trimming to the guide line with a final exact cut by shearing off a thin strip; all the curl goes into the thin waste part leaving an undistorted model part. Easy when you know how! Thanks Allen.

A very nice day out, just the thing to take the mind off the weather! Thanks very much to organiser John Aldrick, to all the exhibitors, demonstrators and traders, and to the 2mm shopkeepers who lightened all our wallets with their usual aplomb.

May 2019 meeting

Alisdair, Alistair, Alastair, Stephen H, Andy, and Nigel met at Graham's house in Edinburgh: the sun was shining after heavy showers on the previous evening.

This was a "show and tell" meeting. Alisdair kicked off by giving us a quick look at what he's been working on recently: a small station building based on Highland Railway prototypes (at Grandtully on the Aberfeldy branch, and Guay not far away on the Perth-Inverness line) which he started at last month's meeting:

The slate roof was made by scribing styrene sheet to give the vertical edges, then cutting single-slate-height strips in the horizontal direction and staggering them when laying them. The  sides are Evergreen weatherboarding. The lamp is scratchbuilt and took a couple of evenings to get right.

He has also been working on some Highland rolling stock from Anthony Yeates' etches: a Diagram 47 open carriage truck:

and a Type A passenger brakevan in early 20th condition after rebuilding from the 1870s rib-sided original:

A restored example survives in the Museum of Scottish Railways at Bo'ness.

We had no time to hear much more about these lovely models however, since a distress call related to a burst pipe and ceiling damage meant he had to leave the scene to dash back home to Glasgow. Maybe he will tell us more next time.

Andy gave us a photo-sequence reprise of Sauchenford's baseboard construction with discussion of the lessons learned - basically, don't use soft-grade balsa as a trackbase, since it compresses when leaned on, causing gentle dips in track level which have calamitous effects on electrical pick-up and thus running quality; and don't use plain plastic point bases (the 2mmSA design has been improved since the version we used). We also discussed the disadvantages of exhibiting a shunting layout where the headshunts are "off-scene": the average exhibition visitor does not understand that  a train is being shunted and will re-appear, but instead assumes it has disappeared and walks off to a more interesting exhibit. Sauchenford's successor is already being discussed but plans remain nebulous.

Alistair showed us the latest tweaks to the track plan of his forthcoming small terminus layout. We discussed whether 4' or 3' board length is more practical, and whether a 12" depth is adequate to create a realistic background. The consensus was that 18" is better, but 12" or less can work if the viewing angles are controlled. Pete Matcham's Kyle of Lochalsh layout was mentioned, where the total depth is 6" or less. Tony Simms' recent work on Hull Bridge with low-relief building silhouettes came up as well.

Alastair discussed his South Queensferry-based layout. He has drawn up the trackplan in Templot and used this as a basis for a 2D outline sketch  from which he developed a 3D model using SolidWorks. This was turned into a plastic point base on his recently-acquired, reasonably-priced 3D extrusion printer, which has a 200x200x250mm work envelope. The advice from the group was to use 2mmSA peg chairs every third chair or so, by providing accurately-positioned holes in the 3D print. The advantage over 2mmSA standard bases is that the exact geometry of any desired formation can be printed. Interesting work. Alastair also discussed his plans for a first loco - he wanted to try his hand at an ex-Edinburgh & Glasgow Railway double-framed 2-4-0, an 1860s W.S. Brown design rebuilt by Holmes in the 1880s and withdrawn shortly before the 1914-18 war. The group's advice was that a 2-4-0 can be hard to balance and the framing would complicate the build, and that it might be better to build a simpler design first, such as an 0-6-0 tender loco. Sound advice no doubt but Alastair did not look like a man convinced. We'll follow his progress with interest.

Nigel had brought along the recently-released N Gauge Society industrial shunter so we could all have a look, and very nice it was too.

He also tried out another member's China-made binocular magnifiers of the type available on Amazon which Tim Watson recommended a few months ago on RMWeb: although the in-focus area is smaller than with normal magnifying spectacles, they allow a much more comfortable, less hunched work position, and are very effective as long as adequate light is available. The difference is plain to see:

Nigel found he could wear the binocular magnifiers over his normal prescription glasses by simply removing the safety lenses from the frame. It's important to use a head-cord (supplied with the unit) to stop them slipping forward when worn due to their weight. Admittedly, they cost three or four times as much as cheaper clip-on magnifiers, but the benefits from the more comfortable working position make this a worthwhile investment.

Nigel also gave a detailed and very interesting discussion and demonstration of progress with another recent project, and showed us some very encouraging samples. I'll not steal his thunder by discussing it further here but we were all fascinated.

And that was pretty much it, apart from a lot of further discussion and consumption of the usual bacon rolls, cake, tea and coffee. Our next meeting is likely to be in Glasgow, exceptionally on the third Saturday of the month, to avoid clashing with the forthcoming 2mmSA Tutbury supermeet which several of us hope to attend.

April 2019 meeting

We had a fine sunny Spring day for our April meeting. Jim, Alisdair, Alistair, Andy, Gordon and Graham gathered at Simon's house in Glasgow. The occasion was the first viewing of Simon's recently-completed loft conversion, a vast, airy, sunny space which he plans to fill with various parts of the Mallaig Extension in BR days. A 2mm scale plan of Mallaig station covered part of the floor, and we were shown the start of the Glenfinnan station baseboard and detailed drawings of the well-known curved viaduct just south of that station. This project should keep Simon out of the pub for many years (or maybe it will drive him to spend more time there ...). We look forward to occasional progress reports.

This month's Short Talk was by Jim, who explained how he'd made the signal wire pulley stakes and the telegraph poles for his Kirkallanmuir layout. He designed a fold-over etch for the signal wire stakes: in practice, the etch (on the right of the laptop screen below) proved insufficently sturdy to be removed from its fret, never mind built and installed.

Not to be defeated, Jim adapted the etches using slices of 0.4mm copper wire as pulleys, and produced a workable design which he installed on Kirkallanmuir. He had brought a further set with him which he added to Sauchenford later in the day.

The characteristic Caledonian Railway A-frame telegraph poles were made from 1.5mm brass rod, tapered using sandpaper and a mini-drill (a suprisingly lengthy process: 10 or 15 minutes per post). Flats were filed at the top of the posts so they could marry to form the "A". The poles and etched cross-arms, again of Jim's own design, were assembled in a card jig made so the cross-arms could sit accurately and square to the posts while they were soldered up.

The insulators includes detail like heavier-duty spindles to lead wires off to lineside cabinets and to signalboxes. A ring of wire at the base of each pole allows them to be easily located in baseboards and removed for transport and track cleaning. Jim sprayed them with black acrylic paint from a rattle can before touching up with dark brown paint, with a dab of slightly-let-down white for the insulators.

After Jim concluded his talk, we lunched on bacon rolls (Simon raised the bar slightly by adding seasoned tomato slices: it's these wee details that matter in the FCAG, and we will be interested to see the response from future hosts) and two kinds of cake. Then it was back to the layout room for Jim to install his signal wire stakes and Alistair to install a few more trees on Sauchenford, and for the rest of us to get on with etched kits and styrene sheet buildings. Jim, ever productive, made a start on another of his own etches for a Caley lattice footbridge for Dunallander (different from the last one). By the end of the afternoon he'd already completed one side of it. You can follow his progress with this model here.

Thanks, Simon, for hosting us so spaciously (not that we're jealous or anything ... ). Next month we plan to meet in Edinburgh, at a venue to be confirmed.