Model Engineer issue 4759 **20 PAGE FREE PREVIEW**

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SPRING TIME FOR A CLASS 4 Join our online community www.model-engineer.co.uk Vol. 234 No. 4759 27 December 2024 – 9 January 2025

Dad dancing for engineers

THE ORIGINAL MAGAZINE FOR MODEL ENGINEERS

ME Beam Engine Restored

Space age toys

Midlands club stands

Getting a pannier onto its wheels

110 Published by Mortons Media Group Ltd, Media Centre, Morton Way, Horncastle, Lincs LN9 6JR Tel: 01507 529589 Fax: 01507 371066 © 2023 Mortons Media ISSN 0026-7325 www.model-engineer.co.uk

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EDITORIAL Editor: Martin R. Evans MEeditor@mortons.co.uk Deputy editor: Diane Carney Designer: Druck Media Pvt. Ltd. Club News: Geoff Theasby Illustrator: Grahame Chambers Publisher: Steve O’Hara CUSTOMER SERVICES General Queries and Back Issues 01507 529529 Monday-Friday: 8.30am-5pm Answerphone 24hr help@classicmagazines.co.uk www.classicmagazines.co.uk

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Vol.234 No.4759 27 December 2024 –9 January 2025

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64 SMOKE RINGS News, views and comment on the world of model engineering.

68 OBITUARY David Carpenter celebrates the life of legendary model engineer Cherry Hill.

PUBLISHING Sales and distribution manager: Carl Smith Director of marketing: Charlotte Park Commercial director: Nigel Hole Publishing director: Dan Savage

70 A GWR PANNIER TANK IN 3½ INCH GAUGE Gerald Martyn builds a 1366 Class locomotive from works drawings.

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75 YOUTH IS NOT ENTIRELY WASTED ON THE YOUNG Peter Kenington discovers a useful source of cheap and willing labour.

77 MIDLANDS MODEL ENGINEERING EXHIBITION DISPLAYS

PRINT AND DISTRIBUTIONS Printed by: William Gibbons & Son, 26 Planetary Road, Willenhall, West Midlands, WV13 3XB Distribution by: Seymour Distribution Limited, 2 East Poultry Avenue, London EC1A 9PT

John Arrowsmith surveys the displays and club stands at the recent Midlands show at The Fosse.

EDITORIAL CONTRIBUTION Accepted photographs and articles will be paid for upon publication. Items we cannot use will be returned if accompanied by a stamped addressed envelope and recorded delivery must clearly state so and enclose sufficient postage. In common with practice on other periodicals, all material is sent or returned at the contributor’s own risk and neither Model Engineer, the editor, the staff nor Mortons Media Ltd can be held responsible for loss or damage, howsoever caused. The opinions expressed in Model Engineer are not necessarily those of the editor or staff. This periodical must not, without the written consent of the publishers first being given, be lent, sold, hired out or otherwise disposed of in a mutilated condition or in other unauthorised cover by way of trade or annexed to or as part of any publication or advertising, literary or pictorial manner whatsoever.

82 WORKING ON THE LATHE: DRILLING AND BORING Neil Raine explains the art of forming holes using the lathe.

86 FLYING SCOTSMAN IN 5 INCH GAUGE Peter Seymour-Howell builds a highly detailed A3 locomotive based on Don Young’s drawings.

89 ENGINEERING’S LOCAL HEROES Roger Backhouse looks at the life of an engineer turned writer - Freeman Wills Crofts.

SPRING TIME FOR A CLASS 4 Join our online community www.model-engineer.co.uk Vol. 234 No. 4759 27 December 2024 – 9 January 2025

Dad dancing for engineers

THE ORIGINAL MAGAZINE FOR MODEL ENGINEERS

ME Beam Engine

£5.10

Restored

http://twitter.com/ modelengineers

Space age toys

www.model-engineer.co.uk

Midlands club stands

David Thomas revisits Arnold Throp’s design of a Corliss mill engine.

97 POSTBAG Readers' letters.

98 UNSEIZING A BEAM ENGINE Mitch Barnes restores a nicely made but neglected beam engine to working order.

100 A SHORT GHOST STORY Mike Joseph recalls an eerie experience on the Settle and Carlisle.

102 A BR STANDARD CLASS 4 TENDER ENGINE Gerald Martyn builds a 1366 Class locomotive from works drawings.

105 BUTTERSIDE DOWN Steve Goodbody writes with tales of the trials and tribulations of a model engineer’s life.

108 SPACE TOYS Henk-Jan de Ruiter recalls the influence of the early space age on the toy business.

110 A RADIAL MARINE STEAM ENGINE Ian Couchman builds a triple expanson marine engine with the cylinders arranged radially.

116 CLUB NEWS Geoff Theasby compiles the latest from model engineering clubs around the world.

ON THE COVER...

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92 A TANDEM COMPOUND MILL ENGINE

Getting a pannier onto its wheels

Completed by L.J. Evans in 1981, this impressive beam engine was brought back to life forty years later by Mitch Barnes (photo: Mitch Barnes).

This issue was published on December 27, 2024.

The next will be on sale on January 10, 2025.

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63

Happy New Year

MARTIN EVANS Editor

DIANE CARNEY Assistant Editor

Martin Evans can be contacted on the mobile number or email below and would be delighted to receive your contributions, in the form of items of correspondence, comment or articles.

07710-192953 MEeditor@mortons.co.uk

64

I should like to wish all of our readers a very happy New Year.

“Surely”, I hear you say, “is that likely, Mr Editor?” Well, I have to concede that things are not shaping up very well. The last year, especially the last three months, has been very far from happy for many people and this state appears set to continue into the new year. The Middle East is in turmoil, the normal state, you could argue, of that region of the world, but made much worse recently by the events in Gaza, Syria and Lebanon. The Middle East may be far away but it is a small world and events there affect us all. European politics is shaky, with the French Prime Minister ousted by a vote of no confidence and the UK led by a minority government (in terms of the number of votes).

Political instability also afflicts Germany, with the collapse of the governing coalition.

On both sides of the Atlantic, there is widespread concern over the election of Donald Trump for a second term. Even an apparently stable country like South Korea is facing problems. The war in Ukraine continues. Where will all this be going in the new year? How can this be a happy state of affairs?

We are, it seems, living in interesting times as the Chinese might say (but probably don’t). It seems we live in a world desperately trying to sort itself out. Politics is a mystery to me so I have to fall back on the conviction that things generally resolve themselves, given time. The grip of terrorism on the Middle East looks like it is weakening; the war in Ukraine is likely to end next year – somehow. I believe it is quite likely that next year will end more happily than it will begin. I take inspiration from the recent reopening (yesterday, as I write) of Notre Dame in Paris, a cathedral resurrected splendidly from the ashes of its near destruction five years ago, and rising even

Cherry Hill. more beautiful than before.

May 2025 follow Notre Dame’s example.

Cherry Hill, MBE I very much regret to have to inform you that Cherry Hill, model engineer extraordinaire, died on Tuesday December 3rd at the age of 93. To use a perhaps rather hackneyed phrase, she was indeed a legend in her own lifetime, and generally acknowledged as the finest model engineer in the country, possibly the world.

This is an opinion strongly supported by her models winning the prestigious Duke of Edinburgh award a total of nine times, a record surely well beyond that held by anyone else.

We include in this issue, on page 68, a celebration of her life by David Carpenter, former editor of this magazine. A comprehensive account of her life and models may be found in his book Cherry’s Model Engines (published by Robert Hale, London, 2014).

Cherry’s funeral will take place at 12:15 on Monday January 6th at Worcester Crematorium (WR3 8HA). All are welcome.

Style and Substance Have you seen the latest Jaguar advertisement?

Stunning, isn’t it? I was left wondering ‘where’s the car?’.

What we were given was a lift

from nowhere, going nowhere, from which eight characters emerged, none of whom looked likely to be purchasing a Jaguar motor car in the near future.

Was any reason given for why we might buy a Jaguar rather than (say) a Ford Focus. Nope.

The advertisement is all style and no substance. Even the style is one that very few could relate to. The advertisement pushes the brand into a very tight niche that few potential customers would want to inhabit, especially at a price tag of £100,000. Is this a deliberate attempt at self-sabotage or is it simply misguided? I wasn’t sure until the name of the new model was revealed. It is to be the ‘type 00’. I think that says it all.

Club Secretaries Yes, it’s that time of year. Your club must surely have arranged your timetable of events for the coming year. If so, please let me know about it as I should like to resume the publication of the Club Diary in the new year.

Cock-Up Corner Well – oh dear – geography weak again, needs attention.

In issue 4757 (November 29th) I claimed that LOWMEX was organised by the Halesowen club. No it isn’t – it is organised by the Halesworth club! My apologies to the Halesworth club and to Kevin Rackham.

Model Engineer 27 December 2024

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Cherry Hill, MBE 1931 – 2024 David Carpenter celebrates the life of a most extraordinary model engineer.

rs Cherry Hill, née Hinds, died peacefully on Tuesday, December 3rd. Our sincere condolences go to her sister, Ro, her family, and her many friends in the model engineering community.

Cherry was arguably the finest model engineer we have seen.

She was born in alvern on ovember th , the second of three daughters.

Encouraged by her father George Hinds, Cherry’s model making career started very early, with the construction of a small chest of drawers.

Later, during the war, she won second prize for a model of a Sunderland flying boat.

After attending St Andrews University, herry started work at the family firm, which made hop picking machines, first in the works and later in the drawing office. uring university vacations, Cherry built herself a Humber special car, based on a 8hp Humber chassis, with duralumin body work on a wooden frame. The engine was retained, along with the gearbox, steering and suspension. Cherry made her

M

own hydraulic brakes. The car was roadworthy and registered for the road in . This was eventually replaced by a succession of sports cars, starting with a T . er first e ercise in model engineering, as with many other beginners, was a Stuart o . t took months to build in the s. herry said for the first time e perienced ama ement that had managed to build an engine that worked.” Models that followed were an Allchin traction engine a vertical engine based on the Stuart a urrell showman s engine, and a Merryweather fire engine. Those early models were awarded bron e or silver medals at the Model Engineer Exhibition.

What followed was quite different.

From then on her models were no longer based on published model designs. verything was based on research using contemporaneous sources, such as old copies of The Engineer and Mechanics Magazine. All these models were unique and chosen because they represented

1

Cherry Hinds with her first traction engine, the Allchin Royal Chester in 1:16 scale.

68

a challenge to make and were capable of being made to work. n many cases the prototype of the model did not e ist, and never had. n some cases, it seemed unlikely that they would ever have worked in full si e but, nevertheless, Cherry made them all work.

Perhaps the most eccentric engine Cherry chose to model was the lackburn agricultural engine, which contained the boiler within the huge driving wheel. ven that was made to work. Nine of her models won Gold Medals and two achieved e uivalent awards. herry was given many other awards including nine Duke of Edinburgh Awards. She received an from ueen li abeth for services to model engineering.

Cherry designed the models at her drawing board; no computer was used or, indeed, owned. All the designs were checked and sometimes original designs were improved so that Cherry’s models could work even if the originals did not. About half the time spent on producing a model was spent in research, preparing working drawings and perhaps

2

Research and design are the most challenging elements of a Cherry Hill model.

Model Engineer 27 December 2024

CHERRY HILL

3

4

Cherry Hill receives the Duke of Edinburgh Award from Chief Judge Ivan Law at the Centenary Model Engineer Exhibition in 2007. making a mock-up model. Only then did the workshop time begin. very last part was made from metal stock, every chain link and rivet. o supplied or bought in items can be found on any of the later models. The craftsmanship is legendary, self taught, and non-digital.

When completed all the models were fully running, usually run on compressed air, with a couple of the models being run on steam.

After being exhibited, all the models were given away, early ones to friends and family.

Later ones can now all be seen at the nstitution of echanical ngineers in irdcage alk, London.

What are the secrets of these wonderful creations? There aren t any, really. verything was made by conventional machining and hand work in a well-equipped workshop.

The ‘secret’ of success is that

everything has to be spot on.

For example, a cylinder made for one engine had a stud boss mm too long, so it was scrapped. ut.. herry, no one could possibly have known would Cherry’s house in Worcestershire was built with a workshop very much in mind.

There were two semi-basement rooms for the machinery and workbenches and a drawing office containing a draughtsman’s parallel drawing board. A separate room at the end of the garage housed a surface grinder and the paint booth. The main equipment in the workshop included several milling machines Myford, Emco and Centec and a number of lathes.

The main lathe was a Myford Connoisseur. There was also an watchmaker s lathe and a very accurate owells lathe for small work. There was also

The Merryweather fire engine captured the imagination and marked the start of some serious model engineering to come. the first lathe from her father, a treadle operated pre-World ar Pittler lathe. There were several drilling machines, an off-hand grinder, a polisher and a bandsaw.

Cherry was married, fairly late in life, to vor ill, a professional toolmaker. y the s herry was becoming noticed as a very good model engineer and her work featured in magazine articles. After one exhibition Cherry appeared on the front cover of Model Engineer. vor saw it and was captivated. m going to marry that girl”, he vowed. Some years later, he did. vor engineered a meeting shortly after seeing that photograph. From that early time he wanted to help Cherry’s model engineering activities as well as persuading her to marry him. He realized she would not accept gifts so he asked

her if he could ‘park’ a new o ford lathe at her workshop.

This lathe eventually went to Cherry’s brother-in-law, Norris omford, and was replaced ultimately by the Myford Connoisseur. Although born in ngland, vor lived in the United States so, until vor and herry married in they remained separated by the Atlantic Ocean, meeting up when visiting model engineering shows in the UK. Since marrying, they divided their time between his home in Florida and hers in orcestershire. vor predeceased Cherry, not far short of his hundredth birthday. herry ill leaves behind an extraordinary collection of unique models, the quality of which is unlikely ever to be exceeded.

6

5

A challenge to the modeller – the Blackburn agricultural engine.

www.model-engineer.co.uk

Cherry Hill visits the Society of Model and Experimental Engineers stand at the Midlands Model Engineering Exhibition 2023.

ME

A GWR Pannier Tank in 3½ Inch Gauge PART 8 – RODS AND PUTTING THE WHEELS ON

Gerald Martyn decides to build a locomotive that he can lift.

Continued from p.54 M.E.4758 December 13

ime to get to grips with the coupling rods. The laser cut parts were listed previously and photo 42 shows the coupling rods as delivered. These come with legs on so they can be gripped in the machine vice to mill the thickness down as required by the drawing. The legs are amputated (hacksaw, no anaesthetic) when all the machining is complete and any remaining marks then filed to match the shape. The rods are 6mm thick, and here it becomes apparent that laser cutting accuracy has limitations as the material becomes thicker. The thinner plates for the frames were bang-on size and the edges were nice and clean but now we have edges that are a bit uneven through the thickness and striated, and for this reason there may be an added material allowance so that this can be cleaned up. All the holes are in the right place, but will need to be reamed to size, and the outer profile is a bit plump

T

70

all round. The drawings (fig 18) show the coupling rod and bush assemblies with some basic dimensions and gives dimensions for the bushes.

Start the rods with some basic milling operations. Mark out lines for the ends of the reduced thickness central section, which if marking from the rod ends should account for the above mentioned extra metal. Grip the legs in the

milling machine vice and mill off to the lines, turning the rod once to keep the machined side where it can be seen. My milling vice is not wide enough to grip all the legs so I just extended it with a couple of (un-matched) pieces of angle (photo 43). To put the slot in the short rod knuckle joint I plunged vertically, pushing gently through at about 0.5mm cuts. This produces a near enough flat surface. lamp the legs flat to the table to mill down the knuckle joint bosses on the long rods. lean up the profile and smooth the faces with files and emery (photo 44). The profiles need not be e act except at the knuckle joint where the rods join together. ere a couple of filing buttons cut from silver steel help to get things right (photo 45). These are just bits of steel free to rotate on a short piece of bar.

They can be throwaway items and there’s no need to harden

42

The rods, as delivered from laser cutting.

Model Engineer 27 December 2024

PANNIER TANK

Fig 18 3 3/8 4 1/2

d

5/32

1/16

3/64

0.01

r1 /

4

9/32

rea m

Ø1 /4

6mm 1/16

5/1 6

6mm ref.

lle dri

Coupling Rods Assemblies Mat’l: Mild steel rods (laser cut parts) with bronze bushes Handed parts, LH shown, 1 LH & 1 RH req’d

sh , bu

/D Ø

6 /1

/64

led dril

Bus hO

Ø5

Ø5/32

Drill & csk for 7BA Ø1/4

Drill Ø1/8 x 5/32 deep Drill Ø1/32 through two places

re am

7 Ø1

h, bus

Thread 7BA Csk head to suit rod

rea m

/3 2

/8 Ø3 r1/4

/64 Ø17

C/b

Ø5 /32

9/32

/8

Ø3

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6mm ref.

2 r5/3

4

ore

3/8 Ø5

1/2

6

Drill Ø1/8 x 5/32 deep Drill Ø1/32 through

r1/

5/32

2 r5/3

C/bore 1/16

25/32 Csk rear hole to half thickness

1/8

3/8

5/32

6

0.01

5/32

/1 r3

/1 r3

1/2

Knuckle Pin And Washer Mat’l: BMS or silver steel 2 req’d

Coupling rods.

43

44

Thinning down a rod.

45

Smoothing the faces of the rod.

46

sing filing buttons to shape the oint.

www.model-engineer.co.uk

Counterboring tool.

them (and it can damage the file ust let them spin when the file makes contact. think I will mention here, also, that on these little engines all the shaping work on the rods can be done with a hacksaw, files and emery. This is how it used to be done before more widespread access to milling machines and, of course, laser cutting. f you have difficulties getting access to a mill then I recommend it (and as a way to keep warm on a winter evening in the shed).

The holes should be reamed, but as there’s only a few thou to take out then a drill may well produce a reasonably accurate hole, or the bush can be made to fit. e perimented on the 5/16 inch hole and couldn’t measure the difference between drilled and reamed but that was with a quality full-price drill. A special counterbore tool made from silver steel, hardened and tempered, is needed to put the 1/16 inch deep rebate into the hole in the front rod. Mine was the one I used on Rob Roy nearly 50 years ago (photo 46), made by ust turning and filing, no need >>

71

47

icking up the centre for drilling and reaming an axlebox. to mill anything. This was used with a spacer collar as a hole filler and depth stop.

The bushes are a straightforward turning job.

Note the leading and trailing ones have 17/64 inch holes to give clearance to the pins.

Martin Evans called for these to be ‘¼ inch full’, which could mean anything. The reason for having a rattling good fit is that when one axle rises up relative to another the length between centres increases (square root of the sum of the squares).

For full travel in the horns, one wheel up and the other down, this would need a rod 0.008

inch longer to avoid binding, which translates to 0.016 inch on bush diameter. Full travel is pretty unlikely (especially as the keep packer limits it but the additional benefit of the slackness is that it provides a tolerance for errors in axle positions and wheel uartering. hen was first told all of this it was suggested that ten thou oversize would be good. That would be a letter drill, if you can find one. I used 17/64 inch and it worked ust fine, and inch oversize has worked for me ever since.

The little knuckle pin that

joins the two rods together may be mild steel, as there’s not much motion here. The space is very tight - 0.010 inch behind the rod, and 0.084 inch in front.

Make the pin using the rod as a trial gauge and part it off just a few thou long at the head. Then fit it to the rod and file the head gently down to near flush. The pin is threaded right through and a short countersink screw can be used to hold the front washer on. If the screw refuses to come out when trying to remove the pin then a bolt with a locknut can be screwed into the rear to resist the screwdriver torque. Now this

48

Marking out for the trailing axleboxes.

72

retention method is obviously not scale. The original had a headed pin retained by a keeper plate and two bolts. When scaled then these bolts came out at around 17BA, so that’s why it needs simplifying. hen the rods are finished then a couple of tools are needed to help mark out the leading and trailing axle positions. The first is a piece of that ground steel bar used for the axles, long enough to span the frames, with a short ¼ inch diameter pin turned concentrically on one end. The other is a short length of silver steel turned to 17/64 inch diameter with a short scriber point concentrically turned on one end. For just the driving axleboxes start by marking the centre points. With one at a time mounted in the four-jaw chuck and hard against the body (or a spacer) to ensure the hole is normal to the faces, adjust to get the centre-pop running true centre finder again (photo 47), and note use of packing to protect bearing faces). Drill and ream the ½ inch hole. Mark a horizontal centre line on the outer face of the other boxes. The motion brackets need to be taken off for the next bit. Fit all the ‘boxes and pass that piece of rod through the driving axle pair. Fit the appropriate coupling rods pair onto the pin and with the little scriber thingy scribe a line on each leading and trailing box. Photograph 48 shows this set up ready to scribe. entre pop e actly where the lines cross and then

49

Plates with centres drilled for quartering.

Model Engineer 27 December 2024

PANNIER TANK

50

Quartering the wheels in the lathe. drill and ream in the same way as the driving pair. Fit the boxes to the frames and try the axles, noting whether the axle truly aligns across the two holes.

My reamer is very tight to size and provides a remarkably close running fit but if the hole is not truly square to the frame and the axle does not meet the far side hole exactly on centre then there will be tightness.

If this happens or there’s any tightness for whatever reason then pass the reamer through both ‘boxes. This will ease the holes hopefully just enough.

Now drill the spring pockets and oil holes. The springs are the ‘standard’ type offered by our suppliers for 3½ inch gauge locomotives. Mine were made from 21 SWG wire coiled to 7/32 inch outside diameter at around 12 coils per inch. ut them down mini drill diamond disc), and grind the

www.model-engineer.co.uk

end as flat as reasonable, so that the free length just supports the axle boxes at the bottom limit of travel i.e. when sitting on the horn stay packer piece. This should give around the right ride height. These springs are rather stiff for such a small model but then this will help suppress any bounce introduced by the vertical component of force from the angled cylinders, yet there’s plenty enough give in them to absorb any likely irregularities in the track.

Fitting the wheels and quartering is easy with Loctite.

By now it must be clear that I love the stuff, but here’s a note of caution. I previously said this was the best, and this makes it a target for counterfeiting so if bought cheaply then it may not be up to standard. I became a bit suspicious of my new bottle, bought on that well known

internet auction site (from a highly rated trader), and so did a quick torsional shear test.

I measured a shear strength around 1600 lbf/in2 (psi), about half the specification value. new bottle bought amongst my next order from one of ‘our’ suppliers (Blackgates) looked rather different and on test I achieved 2880 lbf/in2. This is still a bit down on specification but I think fair for what was a fairly ad-hoc test and without any primer/accelerator.

Lesson? Always buy from a reputable source.

Onward. For each axle, bond one wheel on and allow to set, add the ‘boxes and eccentrics etc. and then the other wheel loosely to check everything is present and correct and in the right order. There’s lots of ways of quartering, and I use a couple of plates with centres to locate the axle and holes for

the crank pins and do the whole job on the lathe. Photograph 49 shows the plates, which are now on their third model so have lots of holes.

Photograph 50 shows the setup in the lathe, with plates sat on the bed and held in place by nipping between tailstock and chuck. Apply Loctite to the loose wheel, make sure it can’t get to the axle box, assemble it all as shown and with the wheel fully on, tap down onto the bed, nip up, and come back in the morning.

At last it can all be put together and rolled up and down the bench to check it runs freely. Hopefully the rods can be fitted with the motion brackets in place if the wheels are turned to back dead-centre.

In theory it’s not possible as the main crankpin is just too long, but with a little bit of running clearance in the rod >>

73

Fig 19

3 1/2 ref.

5/32

6mm

7mm

23/32

16 r3/

3/16

19/32

r1 /1 6

9/32 r7 /3 2

Drill 1/8 x 3/32 deep Drill through to bush Ø1/32

Drill Ø1/8 x 5/32 deep Drill Ø1/32 through Dummy cotter (optional)

Connecting Rod

ream

Ø3

Ø5 /1

Ø1/4

ea m

/4

/1 6r

Ø1

Mat’l: Laser cut rod with bronze bushes & laser cut big end sideplates, bonded or soft soldered 2 req’d

6

bu

sh

O/ D

Connecting rods. bearing it will just work. If there are tight spots on turning the wheels then investigate and then don’t be afraid to take a needle file to the rod bushes if necessary you ll not be the first or the last. Rattling good fit runs best Photograph 51 shows my rolling chassis with an appropriate weight from the right railway to check the ride height.

Finally, when everything seems right then drill a 3/32 inch hole say ¼ inch deep into each joint between wheel and axle, parallel to the axle and in line between the axle centre and the crank pin, and Loctite in a short pin. This will ensure nothing moves in service.

Whilst still in the mood for rods, and while the procedure is fairly fresh in mind, it’s worth doing the connecting rods.

These, too, come with legs for work holding and are machined in much the same way as the coupling rods except there are two thicknesses to get right the little end (3/16 inch) and the rod shank (5/32 inch) see fig 19. The original had a removable big end bearing but having found the coupling rods can just be assembled onto the crank pin then I’ve simplified things here and done it as a simple bush with stickon sideplates to give correct appearance. I degreased and used Araldite, but soft solder

51

would perhaps be a better option. In the event that the rod will not quite go onto the crankpin due to the constraint from the motion bracket then put a small countersink in the rear of the bush and all will be well.

I had intended to steer clear of fripperies and sticky-out bits at this stage and just show the model in its simplest form but on the full size locomotive the big end bearing is held in by such an awesome taper cotter that I couldn’t resist. It’s a fairly easy job as it’s just for show and does nothing useful.

The cotter sits into a groove in the rear of the ‘bearing’, so start by marking out the top

52

and bottom edge of the rod for a hole to line up with the rear edge of the ‘bearing’. Drill 1/16 inch diameter through the rear extension arms and gently down the edge of the ‘bearing’ to leave a half-hole, halfway down from the top and again from the bottom to join up. Now take to the mill and align a 1/16 inch slot drill with the hole and using it as a drill gently plunge cut about 8-10 thou along towards the rear, and again, and again, to make a slot inch long in the top arm and 3/32 inch in the bottom.

This method is gentler on the tool than trying to progress by side cutting. lean up the half holes with a needle file if necessary. Make an over-long taper cotter from 1.5mm steel, carefully round the edges and tap it in from the top, adjust with a file if necessary almost certain) and when happy cut to length. one. The finished rods are shown in photo 52.

To be continued.

Checking the ride height of the rolling chassis.

74

The finished connecting rods.

Model Engineer 27 December 2024

Youth is Not Entirely Wasted on the Young Peter Kenington gives a group of youngsters something useful to do during their summer holiday.

s some of you may know, when not driving Tom Rolt on running days, Matthew and I are building a railway - a somewhat ambitious railway, it has to be said! One day I will get around to writing a full history but, in the meantime, our esteemed editor asked me for a few photos, when he learnt that real, bona-fide young people would be helping out with the building work for a week (less a few days of genuine holiday!).

We actually had two sets of Matthew’s university friends visit over the summer: we started out with Tim, who needed somewhere to stay for a week or so, in order to then take advantage of cheaper flights back to his native Australia. He is a Mech Eng. colleague of Matthew’s and relished the opportunity to do some ‘real’ mechanical work (on our lathe) as well as some railway building, learning to drive our mini-digger in the process. Another of Matthew’s colleagues, Jack, popped down from Bromsgrove for the day during that week (and returned for a whole week later in the summer).

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Tim with a pile of sleepers ready to insert into our wall.

To give you some idea of the scale of our project: it began (with site surveying) in the summer of the first lockdown, has added about 600 hours to the tally on our mini-digger and our most recent purchase was 18,000 rail screws! And yes, we are mad.

We have a long, terraced, (mostly) ‘straight’ section, with loops at either end plus a 50 foot tunnel. Tim helped to finish the retaining wall (photo 1), which is built from reclaimed railway sleepers (their use seemed appropriate in the circumstances).

e recently built our first track panel, which of course needed testing (photo 2).

Matthew picked possibly the most uncomfortable means for doing this - a set of frames/ bogies from a dismantled 5 inch gauge truck, with no seat or padding! It was the nearest thing to hand at the time, so it made some sort of sense to use it.

For the second (late summer) week in which some of Matthew’s friends visited, our team consisted of two young ladies and three gentlemen.

The ladies composed a

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Matthew tests out our first track panel.

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Matthew teaching Mathilde to drive our digger.

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Jack mixes cement, watched (and soon helped) by Charlotte, whilst Ollie tests the brakes on our 5 inch riding truck.

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Matthew moves the I-beam which will become our (somewhat unorthodox) traverser, watched by Kiron.

5 Charlotte mucks-in to help Jack with the cement mixing (they did a lot of this!).

Charlotte and Mathilde do some rail bending. biochemist and a physicist and the gentlemen were two Mech Engs. and an Elec Eng. All worked hard and were generally unafraid to learn/try new skills.

Most had a go at digger driving (photo 3) but also mucked-in with everything else as well.

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Kiron (the Elec Eng.) and I spent most of the time working on a (slightly unconventional) traverser (photo 4) whilst Charlotte and Mathilde worked on track panel building (photo 5).

Ollie did a lot of rail drilling

(and I’m not sure he wants to see another section of rail again any time soon!) but he did get to test the first few track panels we put down (photo 6).

Jack was very keen on cement mixing and was ably assisted by Charlotte (photo 7).

We mixed a lot of cement …!

The team did get some days off and visited Tintern, including the abbey and the Old Station (and its short 10¼ inch gauge line). To continue the railway theme of the holiday, they also took a walk along some of the old track bed from the Wye Valley - Chepstow to Monmouth - line. They then

visited Big Pit at Blaenavon, which also features (static) 0-4-0 and 0-6-0 tank engines; one of each.

At the time of writing at the end of summer 2024, we have installed around 250 feet of dual-gauge track, with another 150 feet of track-bed laid ready for the next sections to be added. We still have a very long way to go, however.

ME

Model Engineer 27 December 2024

Midlands Model Engineering Exhibition – Displays and Club Stands John Arrowsmith reports on the model displays from the Midlands show.

he 2024 Exhibition was graced with some additional club stands and some different demonstrations so that visitors had much more to see and enjoy this year. There was a real eclectic mix of models on show from some very basic and simple models made by young people to the high tech offerings of the gas turbine builders. There were entries in every class except Class 1 for ‘Locomotives up to and including Gauge 1’ and Class 8 for ‘Internal Combustion ngines , reflecting e actly what was in the competition classes.

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Class 2 The 3½ inch gauge model of Peter Wardropper’s 2-6-2 locomotive, River Darenth had been built to the LBSC Betty design and this locomotive was awarded Second Prize in the 2023 competition class.

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The large East African Railway 2-8-2 Class 28 owned by Jeremy Buck.

Class 3 There were six display entries in Class 3 for locomotives in 5 and 7¼ inch gauges this year with some splendid examples.

The largest of these was the East African Railways 2-8-2 Class 28 tender engine in 5 inch gauge (photo 1) which showed lots of fine detail. t is owned by Jeremy Buck. It really showed the difference in loading gauge

sizes between our standard gauge and the African metre gauge locomotives. A 7¼ inch gauge GWR King class under construction by Andrew Auger to the Trevor Shortland design is demonstrating some impressive workmanship and will be a superb locomotive when complete (photo 2).

An interesting version of an LMS Black 5 in 5 inch

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A 7¼ inch gauge GWR King class locomotive under construction by Andrew Auger.

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A Trojan steam engine built by John Wing.

John Swingewood’s LMS Black 5, 4767 George Stephenson with outside Stephenson’s valve gear.

based on the design in the first issue of EiM magazine.

John Wing’s rectilinear or ‘cross’ engine.

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Class 5

A well built 5 inch gauge GWR Pannier to the Doug Hewson design and owned by Paul Swingewood.

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There were six good entries in this class, all showing some high quality workmanship and finishes. ohn ing s Trojan stationary steam engine is a past award winner in the competition class and showed the excellent craftsmanship (photo 6). A rectilinear engine also by John Wing showed the same level of attention and finish (photo 7). A small steam engine and boiler for use in a radio controlled steam launch and made by Derek Morris was a well proportioned unit that will no doubt make a fine boat when fitted (photo 8). The USS Monitor engine displayed by Ian Matthews was an interesting configuration and showed off Ian’s skills. He also displayed a very good example of a freelance grasshopper beam

engine (photo 9 . The final exhibit in this class was the over-crank steam engine Georgina displayed by David Arnold which was, once again, a well built example of the type (photo 10).

Class 6 Here we had two contrasting models to en oy. The first one was a 4 inch scale Garrett traction engine under construction by Richard Betts who is making good progress and to a high standard (photo 11). The other model in this class was a 1½ inch scale model of an Allchin traction engine built by Davis Lambe who has made a super job of it (photo 12).

Class 7 Just one exhibit in this class was displayed by Dave Arnold.

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Myglyd, a 7¼ inch gauge Romulus and tender owned by Ed Parrott. gauge was presented by John Swingewood as this had outside Stephenson’s valve gear (photo 3). Paul Swingewood displayed a 5 inch gauge GWR Pannier to the Doug Hewson design (photo 4) which was well made and captured the essence of these locomotives. Displayed

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on its own stand, the 7¼ inch Romulus and tender, Mygld presented by Edward Parrott was a fine e ample of the type (photo 5).

Class 4 Just one entry in the shape of a 5 inch gauge Welsh slate wagon by Derrick Morris was

A small steam engine and boiler for a radio controlled steam launch.

Model Engineer 27 December 2024

MIDLANDS SHOW

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Ian Matthews built this freelance grasshopper beam engine.

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Georgina, an over-crank steam engine built by Dave Arnold.

An impressive 4 inch scale Garrett traction engine being built by Richard Betts.

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This well modelled 1½ inch scale Allchin traction engine was built by Dennis Lambe.

The 4-facet drill sharpener (photo 13) was nicely made and is no doubt proving to be a very useful piece of workshop equipment. It was based on a design that appeared in Model Engineer magazine in 1987.

Class 9 There were two entries in this class; the longcase Hipp master clock 12 v battery powered free standing example

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displayed by Peter Burton was a smart piece of work.

Unfortunately, because of where it was located, there were too many reflections in the case for me to get a decent photo so I’m afraid I cannot show it to you. The other entry was a novel adaption of a thirty hour longcase clock with an automatic battery powered winder (photo 14) being built by Richard Thomas.

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A 4-facet drill grinding jig built by Dave Arnold.

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A Stuart S50 mill engine built by Luke Mason.

Luke Mason’s oscillating engine and boiler.

18 The unusual 30 hour long-case clock with automatic battery driven winder, under construction by Richard Thomas.

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Sixteen year old Kia Pugh–Bodman is constructing this AEC Matador lorry.

Class 14 This is the class for Young Engineers not in competition and there were three good entries here. Luke Mason, a previous award winner in the competition class, had displayed his example of a Stuart S50 mill engine (photo 15) and his oscillating steam engine and boiler (photo 16). Both were excellent examples and I hope this young man goes on to produce more quality models in the future - I’m sure he will! The third model in this class was presented by 16 year old Kai Pugh-Bodman with an under-construction AEC Matador army truck made using redundant mobility scooter parts (photo 17). This really is a fine piece of work by this young man which augers well for his future involvement in model engineering.

Class 15 In this class was just the one entry - but what an entry! Built

by John Shaw, the quarter scale model of a Vellocette KTT Mark 8 was a superb

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The super ¼ scale model of a Velocette KTT Mk 8 motorcycle built by John Shaw.

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A simple Stirling engine built by John Wing. example of one of these machines. The model was made entirely from scrap material with some small nuts and bolts bought in. It stood out as a very fine model indeed (photo 18).

Class 16 The two very nice hot air engines displayed in this

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A set of metric taps and adjustable dies circa 1912. section were both built by John ing. The first was a simple machine beautifully made and presented (photo 19).

The second engine was more complex but again excellent workmanship and presentation.

To finish this report thought you might like to see some interesting taps and dies I came across, dating from about 1912

they look like they could still do a good job today. I wonder what today’s modern tooling will look like in 112 year’s time (photo 20).

ME

Model Engineer 27 December 2024