S7 Stanier 8F part 10. Curving the tender sides.

Posted on 11/04/2015 by admin

I have started on some of the bodywork for the tender. For someone like me, this threw up some significant difficulties due to my lack of expertise: how to bend the top edge of the tender sides? I have bent sheet metal before, to make the Belpaire firebox of my industrial Garratt, but this was brass, and not a particularly wide sheet of metal, either. The nickel-silver sheet for the tender side requires an even bend along a length of about 11cm. Dave Sharp from MOK has instruction about how to do it, but they are sketchy. The bend covers a height of about 3.5mm in the side, so I worked out that as the bend was through about 45 degrees, a bend of about 8mm diameter would be about right [8×3.5=28mm, divided by Pi = approx. 8mm diameter].
The instructions show how to draw lines on drafting tape inside the bend, to position it accurately. This is good, but how to make the bend? My first try was to place a slightly smaller diameter drill to bend around, and clamp the tender side in my big vice.

However I simply couldn’t bend the nickel silver!
In any case, the drill wasn’t really long enough, and the ends might not bend properly. I was talking/e-mailing Richard at the time, and he suggested I buy a longer rod, of slightly smaller diameter than the bend I wanted to make, and then either roll the sheet over the rod using a rigid metal plate to transmit even pressure, or clamp the top edge of the tender side in the vice and bend the body over the bar. I suppose it was a little foolish of me to try to do it the other way around, but somehow it seemed right to bend the bit that is supposed to be bent, rather than bending the body down whilst holding the part which is supposed to be bent, upright in the vice!
I started to try to bend the sheet over a piece of 1/4 inch (6.3mm) aluminium rod which I found, on our granite kitchen benchtop (the household manager was out), but it was very difficult to bend, and also I thought that this technique might not produce a discrete bend in the flat sheet of the tender side (if you see what I mean), but rather make it a nice continuous curve in the metal sheet. It was impossible to hold the rod still relative to the sheet metal whilst trying to make the bend.
So, back to the vice. The trouble now was to hold everything at once, to allow the rod and the tender side to be exactly positioned. So I used masking tape to hold the rod against the aluminium angle used to make smooth jaws in my big bench vice, as shown on the left.

Then I put the tender sides into the vice and could adjust the position so that the start of the curve was held in between the rod and the vice, the other end of the curve being above this (in the picture one can just make out the second line):

This finally allowed me enough leverage, using a thick rigid steel rule, to make the bend in the tender sides.

It also allowed me, using the same technique, to form the vertical curves at the front of the tender sides (a bit out-of-focus in the picture, sorry).

HAPPINESS !

David

S7 Stanier 8F Part 9 Initial stages of the tender

Posted on 21/03/2015 by admin

Whilst waiting for parts needed for the main locomotive to come from the UK, I have started on the tender. The model kit is designed to have a “compensation” mechanism, which allows the rear two axles to move up and down independently. The front axle is fixed. This is shown in the picture below.

There are two inner plates which rock about the bar which can be seen crossing between the frames. On each plate there are two “loose links” which carry the axle bearings, and allow the axles to move at small angles in the plane perpendicular to the axis along the tender. The loose links are not shown in the picture.

These loose links I have had to modify anyway, to take double-sided circuit board, as part of the adaptation which will allow the wheels to be isolated from the frame, and allow electrical pick-up through a “split-axle” design. On the picture above, for the fixed axle at the front of the tender I have already soldered on the circuit board [it is not exactly straight, but this will be unseen and unimportant when the model is complete].

This picture shows the loose links adapted with circuit board. The left-hand one has the double sided circuit-board soldered to the link. The loose links will have the side parts bent back at right-angles and slid through the slots seen on either side of the bearing holes in the rocker arms seen in the top picture.

The central loose link, seen with the c-b underneath, has had the loose link bored out with a countersink, which then allows the brass bearing to be inserted from the other side, remaining electrically isolated from the surface on the side closer to the camera, which will be in contact with the frame of the tender. This is seen on the right hand loose link.

This way the wheels and axle are isolated from the frames although firmly fixed to the loose links, or main frames in the case of the fixed front axle, seen here.

Fortunately S7 wheels have a wider back-to-back measurement than normal Finescale 0-gauge wheels, allowing the insertion of the c-b.

It is all a complex way of allowing the rear two axles to rock independent of each other. I hope it works, with all the modification to take my split-axle pickup method!

Meanwhile the wheels and other items have arrived from England, and I have been able to put the coupling rods, driving wheels and hornblocks all together into the locomotive frames.

I was not looking forward to this stage, actually, because of my previous experiences – two 0-4-0 locomotives and an 0-6-0, all of which I had problems with at this stage. In all three cases the coupled wheels had suffered from a lot of binding as the wheels went around, presumably because the coupling rods had slight different distances between the crankpins to the distances between the wheel centres. So the thought of all the adjustments necessary on an 0-8-0, and the enlargement of all the coupling rods crankpin holes was not pleasant.

This kit is in a different league.

I put it all together, turned it over, pushed the frames forward, and the wheels rotated perfectly. No binding. Even without any additional weight on the frames. MOK clearly have made the kit with perfect dimensional accuracy, although the correctly articulated coupling rods may help also. Whatever it is doesn’t really matter – it works!

Look carefully on the picture of the frames and you can see the 14BA nuts to be used to put the keeper plates on, to hold the hornblocks in place. 14BA is small, and MOK suggest 16BA!

Scale Seven Model Stanier 8F Locomotive Part 8 – the wheels

Posted on 14/02/2015 by admin

The Slaters Wheelset has arrived, and very nice it looks too.

Coupling rods (articulated as shown), crankpins and crankpin bush

They come with an innovation (to me) from Slaters: crankpins which can be screwed into a boss set on the crank.

However for wheels on an S7 version of the MOK kit, they create a problem, illustrated in this picture:

The crankpins are clearly too long in this case, and their rotation will be obstructed by the crosshead and slidebars.
Now I am familiar with this problem from when I widened the frames and cylinders, etc., for my S7 Industrial Garratt, and actually this doesn’t look quite as bad as that one did. However I will need to shorten the special crankpins made by Slaters (if you look closely I will need to cut them back to move a bit more that the threaded part of the pin), and then I will need somehow to reproduce a thread on the end of what remains.
With the old Slaters system it would have been easy, but here the crankins are completely different. The part threaded to go into the boss in the wheel is 10BA. The smooth part of the pin, to go inside the coupling rod and connecting rod bushes) is also 1.6mm O/D, but the retaining nut screw-thread is 12BA.

After seeking help from the experts/enthusiasts on the WesternThunder website, below is my first plan [I suspect that this is destined only to be the first plan]. The picture shows the frames with wheels in place. The front end is on the left. I am going to take advantage of the special construction of the S7 wheels, with the 10BA tapped holes for the crankpins.

I am lucky in having my friend in Melbourne Richard Davidson who has done some work on his lathe for me. Below the frames in the picture are the special crankpins which Richard has made for me.
My illustration shows how I hope to arrange the crankpins. From the front: axles one and two have the special crankpins in place. Axle one the pin is part-way through the coupling rod. Axle two has the crankpin all the way home. Axle three and four have the Slaters crankpins. The ones for the connecting rod wheels are longer, and will take two brass bushes on top of each other, through the coupling and connecting rods. The final axle will have a standard Slaters crankpin and bush.
Clearances will remain extremely tight at the front end. I intend to try the front crankpin fitting direct to the wheel without a washer. The boss on the coupling rod is slightly thicker than the body of the rod itself, so as it goes round it should be clear of the central wheel boss. The second wheel will need a washer, though: the articulation of the coupling rod will catch on the central wheel boss otherwise. By the third axle, fortunately, the clearances should be less critical. So the flat portion of the Slaters crankpin, acting as a washer, will be less critical.

I hope that it all works …..

Model 8F Part 7: Cab re-construction

Posted on 26/11/2014 by admin

Following on from part 6, I found out from MOK (Dave Sharp) that I had definitely put the base of the cab on upside down. This has all sorts of minor but annoying effects. One was the fact that the formers inside the base of the cab had been made to accommodate the etched plates which were meant to go inside the curved sections (making them invisible – they are there only to make curving these areas easier). So the formers made the curved plates have a larger diameter of curve – hence leaving a gap at the outer end: exactly where I had found one.

After much debate inside myself, I decided that I would never be happy if I did not do the job properly, so I pulled all the cab base apart using a 75 Watt soldering iron. Once back to the component parts I tried to clean all the solder off the nickel-silver, then I flattened the bottom plate completely (apart from the front plate [see below]) first with my fingers, then with a tap hammer on a piece of flat granite. The front plate (with three holes) is now bent upwards as it should be.

I then reformed the curves, fitted the formers back (now easier because the former correctly fitted onto the curved sections. At the point shown in the picture, my soldering iron stopped working. So I have sent off for a replacement.

Whilst I wait for a new 25 Watt soldering iron, here is a picture of the completed boiler backhead.

I am quite pleased with it. Basically I followed what fittings I could see on photo.s of preserved and other engines, and then upt as many pipes as I could on the brass castings, to be realistic. I “painted” it using metal blackener, scraped some off the copper pipes and painted the dials and water gauges by hand. A thin covering of matt varnish to complete the work.

Model 8F construction Part 6

Posted on 12/11/2014 by admin

I may have made a mistake, which has exposed a difficulty/problem with the etches, not related to ScaleSeven however.

The first picture shows the overall basic construction of the cab: there is an undefloor part which I guess if faithful to the protoytpe, but is completely hidden one the parts are put together!

On the underneath of the cab is part no 362, which is curved upward to make the curved plates leading up to the footplate.

This shows that I may have put part number 362 on the wrong way up. I am guessing this because the three holes to take the damper levers have ended up on the wrong side. However putting it the other way up would mean that the fold for the panel at the front with three round gaps in it would be on the wrong side to bend it downwards – ie the bend would be away from the etched line. This is why I used it the way up which you can see in my pictures. Also the half-etched areas at the front on the curved plates I thought must be on the outside, because otherwise they would be completely hidden!
So, if my analysis is correct, either the three holes for the damper levers are on the wrong side, or the etched line to fold the front plate is on the wrong side.
If you look at picture No.s 3 and 4, you can see that despite my care I have ended up with a gap between the cab-side etches and the curved part of part number 362.

On the right side this doesn’t matter, because if I push the curved part upwards, it neatly fits behind etch number 367 (this is the front of the cab, immediately behind the whitemetal firebox I think). This allows the shiny (unetched) strip at the side of the curved part on 362 to line up with the shiny strip along the lower edge of part number 367. Fine, it looks made to do just that. There will then be no gap along the bottom of the cab-side etch. The trouble is that on the left side, the curved part on 362 just abuts the thicker edge of part number 367 rather than going behind it, and leaves the curved part on 362 with a gap between that and the cab-side etch. This could be cured by removing a mm from the upper edge of part 362, but I’m reluctant to do that without knowing that it really needs to be done. Also with the assembly done so far, it will be awkward to do. However advice from the Scale Seven fraternity on the Western Thunder website suggests that I have put the base on upside-down and the removing a mm from the curved part is therefore exactly what I will have to do.

While I wait for the S7 wheels (for them to be sent to Aus., I want the whole lot at once, and I gather Slaters haven’t produced the pony truck wheels yet, although the others are ready), I have also been putting the details on the backhead.

It looks good so far, but it has been difficult to identify exactly where all the tiny lost-wax castings go.

I need to find views of the inside of an 8F cab, showing the backhead. The “Locomotive Profiles” books have two, but one is of an oil-burner, and the other one doesn’t seem to have the same components as provided in my kit. Mostly it is the same, but some parts are seemingly missing from the kit (the one described in the book as the “independent steam valve”), and doesn’t appear to be a casting either for the “blowdown valve” or one which goes where the steam sanding valve should fit, between the left water glass and the brake handle. There is a casting which can be seen in my picture placed in position, but if fixed there it will obstruct the regulator handle.

The pictures that I found via Google images didn’t help. Again I have turned to the WT website for help, and I am a little closer to answering my questions now. Later versions of the 8F don’t have the sand gun control valves in the centre of the backhead, and there are some other little details which I will have to change.

More pictures when it is done ….

Stanier 8F in Scale Seven, Part 4

Posted on 12/08/2014 by admin

Onto the next bit. Whilst I wait for the S7 wheels to become available, I have tried to progress with other parts of the engine. The next bit in the instructions which I have is the pony truck. So I started on this.
Here is the basic construction.

As can be seen, there is no compensation on the pony truck. I doubt that this is necessary, because there will be a little bit of lateral sway of the mechanism once in place, and so with only one axle surely compensation will not be required?

So should I add weight to the box-like centre of the pony truck? I decided to do so, and carved a piece of lead weight from a truck-tyre balancing weight obtained from our local tyre-fitting place, to fit in the centre of the pony-truck.

Of course I’ll have to wait a while before seeing if this works!
Incidentally, I have a works diagram of the engine, and the frames of the pony truck in this kit are the correct distance apart (±0.5 mm, which is good enough for me) without modification.

Next I constructed the rear steps, and the moved on to the front footplate sub-assembly. This is a great example of how the parts can be put together “dry” – no solder – because of the excellent tab-and-slot construction.

Frames and footplate from opposite the rear steps. The footplate is stopped from fitting down onto the frames by the upright used to hold the motor.

In making this sub-assembly, I came across a minor problem.

Frames and footplate seen from the front quarter. Note the front footplate sub-assembly is in place on the main footplate etch.

As can be seen in this picture, the problem is that the upright frame for the motor mount has a width of 29mm, whilst the distance between the edges of the footplate is 26.5mm.
It’s not a major problem, at first glance, and probably the answer could be simply to make a couple of small cut-outs in the footplate – 1.25 mm each side is only a small amount. However before doing this I asked on a Scale Seven Web forum called Western Thunder (westernthunder.co.uk) to see if there was an alternative solution which anyone could see. Making cuts in the footplate is all very well, but what the effect on the later construction and the overall end-appearance I couldn’t yet tell.

It was suggested that the inside width of the footplate had been narrowed (making the footplates on either side a little bit too wide) in order to fit the narrower frames in Finescale 0-gauge. This proved to be correct, so with my correct width frames I need to file or cut off some metal from the inside edge of both sides of the footplate to make it match with the top edges of the frames.

The footplate is exactly the correct external dimension, but the footplate width on each side is 16.7-16.8 mm. Taking this back to the correct width of 15mm will remove the line of rivets. I could probably re-create these, however. Probably it would be best to line them up before I file back the inside of the footplate edges. The nickel-silver sheet, even over the etched areas, is still 0.5mm thick. This will affect the small slots used to locate some other parts. I don’t know as yet what parts are affected, but I will just have to find that out as I go along, I fear.

I was just about to set off and form the rivets on the footplate, then take 1.5mm off the inside of each footplate side, when another factor entered my brain, and it is just as well (I think) that it did.
If I took 1.5mm off the inside of each side of the footplate, then the whitemetal cast firebox would no longer fit as intended on the inside edges of the footplate.

This might not matter, because the firebox would still fit on the frames themselves.

So if I made the inside dimension of the footpale sides nearly the same as the inside dimension of the frames then I thought that it would work. The inside dimension of the frames is 28mm. The inside dimension of the footplate is 26.5mm as supplied.

So if I took 1.0 mm off the inside of the footplate each side, the edges would sit on the middle of the frame each side, which would probably look OK, and the firebox could sit on the frame edges. The only (?!) problem to remain would be that the line of etched rivets on each inside edge of the footplate sits right on top of the line to which I would need to reduce the footplate inner-dimension. Tricky.

So it was tempting to leave the footplate as it is, just cut back the motor-mount. However this would leave the footplate overhanging the inside of the frames, which would not look very good. File the original etched “rivets” flat, then reform them with my special rivet tool?

In all of this, advice from members of the WT forum showed me that I was going to have to cut the motor-mounting back, and reinforce it from within the width of the whitemetal firebox. A slightly daunting task, but eventually I’ve taken the plunge ….. Bitten the bullet ….. etc.

I used some rectangular-section brass to strengthen the motor mount, soldered into place.
Then I cut off the frame uprights, and part of the motor mount. As can be seen, the footplate can now lie on the frames. Good.

Even better, the firebox goes over the motor mount!
In this view it is possible to see how well this model goes into the ScaleSeven arena: the firebox is exactly the correct width, even though the model was originally intended for Finescale.

Inspecting the footplate now, it becomes clear (see diagram below) that I will only have to shave the 1mm off the inside of the footplate for the length between the two vertical arrows which I have put on the picture.
The rest is covered by the parts representing the frames above footplate level.

The angled arrow shows one of the slots into which the parts representing the frames where they are visible above the footplate will fit: just outside of the firebox moulding.
Interestingly, they are exactly 29mm across the outside dimension – as are the frames which I have built.

Of course I shouldn’t be surprised really, but it is reassuring.

Stanier 8F in Scale7 part 3

Posted on 08/06/2014 by admin

Cylinders, slidebar, crosshead and some valve gear.

I have been contructing part of the valve gear, as shown.

The detail of this kit is such that the combination lever, with a complex shape at its top, if faithfully reproduced. Unfortunately this means that the where the lever goes through the crosshead of the piston valve (see the diagram at the top for the names of these tiny bits of brass!) it is such a tight fit that there is not enough movement in the model form.

These are pictures of the piston valve shaft and crosshead (all one moulding) and the combination lever. Unmodified as yet.

Combination lever – unmodified

Piston valve shaft and crosshead – all one piece of “lost wax” casting.

They both have to be carefully filed back to allow the combi. lever to move through an angle of about 25 degree either side of verticle in the crosshead.

The story so far: frames with both cylinders, motion brackets and valve gear attached

Click to see progress.

Old ‘blog entries – building the Industrial Garratt locomotive (2011 entries)

Posted on 24/05/2014 by admin

Actually, this is a tale which goes back to before the coulshed.com website existed, and then the website changed (at the beginning of 2012), so I am reconstructing the entries from before January 2012, in order.

Painted and airbrush weathered from above

Click on any picture to enlarge it !

The start of making my model industrial 0-4-0+0-4-0 Beyer-Garratt in Scale Seven goes back to the middle of 2010. The kit was a decade in my cupboards waiting for me to summon the courage to tackle four sets of valve gear, never having constructed a model with valve gear before! The kit was a very basic one, designed for Finescale, “0-gauge”, and I decided to make it with near true scale-width frames, as well as the rest of S7 standards.

This meant that my first difficulty was to adapt the spacers for the driving-unit frames. The kit had “fold-up” frames, held also at the desired width by the buffer-beams and spacers on the inside end of the driving units.

I was also planning to fit suspension to every axle, so slots to accept the suspension unit had to be cut in the frames themselves.

This picture shows the flat fold-up frames with the scored markings to cut out the wide slots for the suspension units. The actual frames are seen above and below a horizontal plate, with the original axle holes about to be cut out.

The buffer-beams and other spacers had to have new slots cut into them at the new width (29mm).

In the end the slots were just widened and scrap brass added to set the width of the frames, as shown.

Frames upside down to show the slots for the suspension units

This was all very worrying, as it appeared to be a very destructive approach to kit-building! Fortunately all the calculations appeared to be working when I assembled the frames, as shown.

Front driving unit, from the front.

If you look carefully it is possible to see where the buffer-beam slots have been widened for the scale-width frames.

There then ensued a long struggle with the suspension units, the wheels, the “plunger” pick-ups and the coupling rods, just to get the units to move under their own power.

So many times I wondered if it was beyond me ….

This takes us up to the start of 2011, and the start of our website. The valve gear was yet to be done.

April 2011
I should be able to put together some more of my model Garratt locomotive – an 040+040 industrial steam engine. Here’s a picture of the front end driving unit as so far built. The trouble building this to exact scale dimensions (Scale Seven) is a story in itself ….Looking after (ie staying in the house at the same time) as the two boys has some advantages: I took some time to construct some more of my Garratt.

Here’s my first ever construction of outside valve gear for a model steam engine – and it moves ! What makes it difficult is to make the joints all move. On the assembly shown below there are five joints made with brass pins soldered to etched brass valve gear “rods”. the pins are about 0.8mm diameter, 5mm long, and clearly the solder only has to fix the pin to one rod, and not the other. There are about ten joints like this for each set of valve gear – and there are four sets.
I’m very proud to have successfully complete one!

June 2011

As you can see, both sets of driving wheels are now complete with coupling and connecting rods, plus valve gear.

If only I could put moving pictures on the website, I could proudly demonstrate how it all moves and proceeds along the track!

I have now fitted the bunker and the water tank onto the diving wheel assemblies of my model Garratt locomotive ….

October 2011

My model of the industrial Garratt “William Francis” is coming along quite well, now.

The first picture is of the two end units, with the rear one containing the coal bunker on the left and the front unit with a water tank on the right.

This is the central unit, with the boiler and cab.
It’s a very complicated model, and the kit (originally bought by me over a decade ago), is far from perfect or comprehensive. It’s really just a starting point for building a model of this industrial locomotive – adding detail is very much needed. However that is the part which I enjoy most, so that is certainly OK by me.

November 2011

My Garratt. It’s an 0-4-0+0-4-0 locomotive. The prototype ran in an industrial complex centred around a large coal mine in Warwickshire. It’s taken me a year to get this far, being quite a complex project. Here you are, though. Just three minor details to go (nameplates and a clack valve on the right hand side of the boiler).

Then it will be on to the painting …

December 2011

So what have I been doing?

Well, the Garratt has progressed. The construction is now finished, and I’ve put the primer on it. It now looks a little like the prototype did when it emerged from the Beyer-Peacock work in Manchester and had its picture taken in “works grey”:

Also, I have decided that I should but no more model kits until I have built the one that I already have! A radical approach I know, and judging by the article that I read, many other people have multitudes of kits lying arond the house waiting to be started. The first benefit of this policy is that I have started to make the model of an LNWR gunpowder van. I’m not sure that the LNWR ever actually had such wagons. I have never been able to find a photograph of one like this kit is supposed to represent, and the instruction sheet which comes with the model is vague, inaccurate in parts, and covers several different models. The attraction of the model is that the LNWR is reputed to have painted these gunpowder vans vermillion, so I could legitimately have a bright red wagon on my railway! There is some doubt that this colour is true: the claim about the colour may be based upon a crude tinplate model made by Bassett-Lowke in the nineteen-fifties! Nevertheless I shall build one.

Here it is (as far as I have reached!):

For more entries, follow the links at the top or bottom of the pages, to go to “older posts”.

Video files from Melbourne

Posted on 23/05/2014 by admin

It has taken me some time to get these loaded, but here are a few video files of Richard Davidson’s circuit of track at his home outside Melbourne (a place called Melton). This outdoor circuit is huge! Richard tells me it is 60 yards around the loop, which is about a scale 2½ kilometers!

My industrial Garratt ran well, and so I want to celebrate this fact!

There are small files and larger ones, depending on how broad your broadband is

(is it a Gillard-government one, or an Abbott govt. one?).

WF outdoors 1 small <-Small Large -> WF outdoors 1

We loaded up the Garratt with 27 wagons: WF at RDs house

WF outdoors 2 small <-Small Large -> WF outdoors 2

I don’t think that the real one could have hauled this many!

WF outdoors 3 small <-Small Large -> WF outdoors 3

In the last video it is possible to see Richard’s superb model of a North British 0-4-2 locomotive going in the opposite direction around his double loop of track.

Scale Seven in Melbourne

Posted on 19/05/2014 by admin

I spent a pleasant day in Melton, near Melbourne. It was a day-trip (!) from Sydney to see fellow-ScaleSeven enthusiasts Richard Davidson and John Ritter. The original idea had been to go to the VicG0G meeting, but somehow we never actually made it there.

This was mainly because Richard has a wonderful outdoor circuit, upon which we could run our trains.

Richard has a large shed in the back garden, out of which the railway comes. It then goes around a circuit of more than 50m of track and back into the other side of the same shed.

As you can see, I took my industrial Garratt (William Francis) down to Melbourne with me. I’m pleased to say that WF ran very well during the day.

The Garratt could haul a load of 27 wagons, which is the most it has ever pulled. I do not have that many trucks myself, and in any case Richard’s wagons are better -built that my own, and offer less rolling-resistance, I suspect.

It drew 450mA current with or without a load of wagons, which is good even though it means there is probably too much friction in the locomotive running gear itself. It ran so well that we left it running round and round for hours, which probably loosened up the running gear nicely.

Richard has some lovely locomotives as well as his magnificent collection of private owner wagons.

This one is Caledonian Railway 0-4-2 No 705, designed by George Brittain and built by Dubs in 1881.

As usual, click on pictures to enlarge.

In Richards words: it is scratchbuilt except for the gears (plastic, two start worm, 11:1 ratio ex motor car window winder). The motor is ex computer, from Proops at $2.50, draws 12 mA light, 30 mA with gearbox and about 100-200 mA on a train. The wheels were fretted out of brass and insulated with a strip of thin perspex between the centre and the tyre.

The second one is North British Railway 0-4-2 No 26, a mixed traffic engine built in 1845 by R & W Hawthorn of Leith. The original was fitted with a patent valve gear in which reversing and cut-off were controlled by separate levers. The valve was in two parts that slid over each other and the valve rod was hollow, with the cut-off rod inside it.

Again, Richards words: I built the engine with a crank axle but have got no further with the valve gear. The motor is a Mashima 1824 in the firebox, driving through a cut-away (27:1) North West Short Lines idler gearbox. The final drive gear is on the axle between the eccentrics and the idler gear is meshed with the worm in what is left of the gearbox. The mesh between the drive gear and the idler can be adjusted. The engine is also scratchbuilt except for the motor and gears. The livery is guesswork..

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