Model Engineer issue 4761 20 page preview

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IMPROVING A MYFORD ML7 Join our online community www.model-engineer.co.uk

Vol. 234 No. 4761 24 January – 20 February 2025

Sirius valve timing

THE ORIGINAL MAGAZINE FOR MODEL ENGINEERS

A daytrip to Worthing

Making rods for a Mogul

Cylinders for a pannier tank

A young engineer’s first project

188

218 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 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

Vol.234 No.4761 24 January –20 February 2025

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

188 WE VISIT THE WORTHING & DISTRICT SME John Arrowsmith visits a well equipped club on the south coast.

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

193 A TANDEM COMPOUND MILL ENGINE

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

197 FRED – A 5 INCH GAUGE LOCOMOTIVE Young engineer Spencer Priddy describes the construction of his first locomotive.

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

203 ML7 MODIFICATIONS Mike Joseph catalogues the various improvements he has made to his Myford lathe.

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.

206 AN ELECTRONIC CONTROL SYSTEM FOR A TRAVERSER Peter Russell brings modern technology to the Sunderland club’s trverser.

208 POSTBAG

217 BOOK REVIEW Roger Backhouse reads about a roadside tramway in Wantage.

218 KEMPTON STEAM MUSEUM Robert Hobbs has a go at driving the largest triple expansion steam engine in the world.

223 STUART TURNER SIRIUS PISTON VALVE Graeme Quayle discovers, and resolves, a problem with the valve timing.

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

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

Future events.

212 OBITUARY - PHILIP BELLAMY Martin Goddard remembers the life of a leading member of the Surface Warships Association. .

Vol. 234 No. 4761 24 January – 20 February 2025

Sirius valve timing

THE ORIGINAL MAGAZINE FOR MODEL ENGINEERS

A daytrip to Worthing

http://twitter.com/ modelengineers

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

ON THE COVER...

IMPROVING A MYFORD ML7 Join our online community www.model-engineer.co.uk

Andrew Breese, Worthing club president, takes his 5 inch gauge B1 locomotive around the track (photo: John Arrowsmith).

£5.10

Making rods for a Mogul

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Doug Hewson leads us through the construction of the BR Standard Mogul.

234 CLUB DIARY

Readers’ letters.

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http://www.facebook.com/modelengineersworkshop

213 A BR STANDARD CLASS 4 TENDER ENGINE

Cylinders for a pannier tank

A young engineer’s first project

This issue was published on January 24, 2025.

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183

All Change

MARTIN EVANS Editor

DIANE CARNEY Assistant Editor

The editor can be contacted via the email below and would be delighted to receive your contributions, in the form of items of correspondence, comment or articles.

MEeditor@mortons.co.uk

184

Eagle-eyed readers will have noticed that the dates on the front cover of this issue indicate a ‘lifetime’ of a full month rather than the customary two weeks.

This indicates a major change in the way that Model Engineer is published. After this issue, Model Engineer will become a monthly publication. Furthermore, the magazine will incorporate Model Engineer’s Workshop, which will now cease to exist as a separate magazine and the title of the combined magazine will be Model Engineer and Workshop. This raises a number of questions, which I will attempt to answer here.

First, a little history. The Model Engineer and Amateur Electrician started in January 1898 as a monthly magazine, selling at tuppence an issue.

Less than three years later, by popular request, the magazine became a twice-monthly publication, starting from the September 1900 issues. The magazine didn’t last long in this form though, and became a weekly publication from January 1st 1903. From the 1st of May 1963, the magazine became once more a twicemonthly publication, promising ‘a refreshingly modern style, with more pages and printed on better paper’. From about the beginning of 1997, that switched to fortnightly and has (as far as I can tell) remained in that form until now.

A major change came in the summer of 1990 with the launch of Model Engineer’s Workshop, with editor Stan Bray, who was at the time Club News editor of Model Engineer.

As the name suggests, this magazine focussed on workshop techniques rather than the construction of models. Inevitably, this led to a reduction in the workshop content of Model Engineer. The new magazine was quarterly at first but soon became bimonthly and then monthly.

The reorganisation of the two magazines into a single monthly publication is, I believe,

a rational move, taking the magazine back to its original concept of a monthly, wide ranging magazine for model engineers. The new magazine will be substantially bigger than either Model Engineer or Workshop and promises a bigger, brighter and more secure future. The editor of the new magazine will be Neil Wyatt, the current editor of Model Engineer’s Workshop, so the new magazine will be in good hands.

Your Subscription Update If you are a Model Engineer subscriber, your subscription will be transferred to the new Model Engineer and Workshop magazine. You will receive the same number of issues remaining on your current subscription.

If you currently subscribe to both Model Engineer and Model Engineer’s Workshop, your Model Engineer and Workshop subscription will be extended by the number of remaining issues from your Model Engineer subscription.

Direct Debit Subscribers: If you have a Direct Debit subscription to both Model Engineer and Model Engineer’s Workshop, you will instead receive the remaining issues as The Railway Magazine, another title published by Mortons Media. Your Model Engineer’s Workshop subscription will remain unchanged, albeit a new title name Model Engineer and Workshop.

We understand this might not suit everyone. If this is the case, please contact us at 01507 529 529 or email emailqueries@mortons.co.uk, and we’ll be happy to suggest an alternative magazine or arrange a refund if needed.

For those who subscribe to Model Engineer’s Workshop only, your subscription will continue as usual, and you’ll receive the new Model Engineer and Workshop magazine, now bigger and better!

Key Dates: The final issue of Model Engineer will be Issue 4761, on sale 24 January 2025.

The first issue of Model Engineer and Workshop will be Mar-25 on sale 21 February 2025.

Thank you for your continued support!

Farewell This reorganisation of the two magazines provides me with a good opportunity to retire, which I have been anticipating for a little while.

I have a number of projects that require my attention and I need some relief from the rather strenuous, but highly stimulating, effort of turning out a fortnightly magazine.

I had always rather fancied the idea of becoming editor of Model Engineer and – lo and behold! – the opportunity came, quite unexpectedly, when I was asked to stand in for Diane when she had to take a break back in 2017. This continued, of course, when that turned into a permanent position, giving me seven years in the editor’s chair. It has been a great privilege to undertake this task and I shall hope to continue to be involved, as a contributor, from time to time in the future.

I should like to thank those who have generously helped and encouraged me, as a mere amateur in the publishing business, in getting ‘up to speed’. Most especially, my thanks are due to Diane Carney, Mike Chrisp, Chris Rayward and the late Chris Deith. I should also like to thank Steve O’Hara at Mortons and all my contributors, who have supplied me with a steady stream of very varied and interesting material. Thanks are due to you readers for buying the magazine and keeping me in a job! I am also very grateful to have made so many good friends during my spell as editor, which is a wonderful bonus. Thank you!

Model Engineer 24 January 2025

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We Visit the Worthing & District Society of Model Engineers John Arrowsmith visits the Henry Greenly Memorial Railway in West Sussex.

188

bright, warm, spring day dawned for my visit to the Worthing & District Society of Model Engineers which is located at Field Place, situated about a mile from Worthing town centre. The impressively smart club site is in an attractive area and has been built by the members to blend in very well with its surroundings. I went on one of the club’s working days and was met by vice chairman, Geoff Bashall who introduced me to the many members, working away and chatting about their various projects (photo 1). It really is an immaculate site with neatly mown grass areas, which are available to the public during open days, and a very smart and substantial brick-built clubhouse along with equally impressive infrastructure.

The present club was reformed in 1974 following the demise, in the fifties, of an earlier club. In 1974 five founder members, Andrew Reese, Bert Perryman, John Rea, Victor Hodgson and John Edwards started the present day set-up and within six months membership had risen to around 60. Present day membership is around 110 including honorary members.

The site at Field Place is owned

by Worthing Borough Council through a private charitable company which has access to a variety of grants etc. for the listed buildings within the

A

1

The group of happy members posing for their team photograph.

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A superb clubhouse and patio area adjacent to the footbridge. park, grants which otherwise would not be available. The relationship between the organisations is very good because the council like to see the local population enjoying the park facilities so members here enjoy their club without any real problems.

The clubhouse and workshop was built in 1992 and has an attractive outside appearance with a large canopy over a passenger loading area (photo 2). Inside it is equipped with all the facilities needed by members and guests in, again, a very smart environment.

Model Engineer 24 January 2025

ME VISITS

3

4

The main signal control panel located in the clubhouse.

Some of the fine models and storage units in the clubhouse.

Members and club models are displayed in a side area where the multi-gauge 2½, 3½ and 5 inch track and signal controls are located (photos 3 and 4). A good sized kitchen area has a serving hatch to the main room which has comfortable seating and all the usual trimmings that model engineers enjoy. There is also a very good 00 gauge

layout, built by members, within the club room which is fully operational and scenic; indeed, it includes a working funicular railway as well (photo 5)!

All the track signals are automatic using a 24 volt system that uses old style relays for interlocking so that trains are always kept safely distanced during running

5

A section of the OO gauge layout showing the working funicular railway.

7

The traverser from the steaming bays to the main circuit.

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times. The ground has been landscaped so that the main line runs in a loop like a folded figure of eight, so that it crosses over itself during the run (photo 6) and provides some interesting gradients and also some good long straights to enable spirited running (no doubt), if the track is not fully occupied. It is about a quarter

of a mile long on a full circuit.

A number of steaming bays adjacent to the clubhouse and bridge are connected to the main line with a flat platform traverser (photos 7 and 8).

The club holds a charity open day once a year and one member has access to sponsorship, meaning that whatever amount is raised by the club is match funded by the sponsors and the total benefits a local charity. Last year it was a total of about £2,000 which is an excellent amount, and was no doubt well received. At Christmas time they enjoy the traditional Santa runs where parents and children can enjoy the festivities and meet Santa, without any extra charges for the day out. This helps the local community and is much appreciated.

The first member I spoke to was Geoff Symes (big Geoff), the club’s chief engineer who was busy having a steam test on his 3 inch scale Burrell

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An impressive tunnel portal on the circuit with part of the line running above it.

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From the other side showing how the traverser connects to the main track.

189

9

10

Geoff Symes tends his 3 inch scale Allchin which is at the club for a steam test. traction engine which looked resplendent in the bright sunlight (photo 9). I was also in time to see chairman, Kevin Ayling using the club’s new portable testing equipment bench to test a couple of safety valves (photos 10 and 11). This very useful piece of kit has a gas fired boiler and various outlets to enable different sorts of fittings to be tested under steam pressure. It is all mounted on a neat aluminium trolley for ease of moving around the site. The novelty is that every component was donated by members so that the total cost was around the £50 mark, which seems excellent value for such a useful facility.

At this time club president, Andrew Breese had his 5 inch gauge B1 in operation; it was traversing the track very well and seemed to have plenty of

steam and power for the short train it was pulling (photos 12 and 13). Another fine example of a Class 33 diesel electric built by the late Alan Norman was also being put through its paces on the track. The builder had copied all the main details directly from an original example located on the Watercress line in Hampshire - and it showed! (photo 14).

Long time club member, Jim Alderman fired up his 5 inch gauge Sweet Pea, Vera May and he too enjoyed some good running time on the track (photos 15 and 16).

Talking with Geoff Bashall, the vice chairman about membership was very interesting because he said that the numbers here have been over 100 for the last 25 years at least and that they have a good mix of ages with some skilled

11

The set up of the smart new portable test bench.

190

Blowing down the new test rig built by club members. younger people attending as well. He mentioned an observation made by the wife of one member who said that, generally speaking, as people get older they lose the sparkle in their eyes. When you come to a model engineering society

and see the older members running their engines and being involved with the club, however, they still have that sparkle. I thought that was a very profound and interesting remark which I also think is very true. Model engineering

12

The fine 5 inch gauge B1 owned by the club president, Andrew Breese.

Model Engineer 24 January 2025

ME VISITS

13

14

Andrew Breese takes his B1 for a spin around the track.

15

A fine Class 3 BO-BO Diesel electric locomotive built by Alan Norman.

16

Almost ready for a run.

17 Jim has plenty of steam as he starts his journey round the track.

18

A well equipped workshop within the club building.

Club member, 92 year old John with the LBSC lamp.

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certainly has that benefit of keeping older minds actively engaged for far longer and this in turn leads to a longer and, hopefully, happier old age. One member who was there and thoroughly enjoying himself was 92 year old John who told me of his interests and how, together with his son who is also a member, he still gets involved with the

club. It was a real pleasure to meet this venerable gentleman (photo 17).

A useful workshop has all the necessary equipment to enable running repairs and maintenance to be carried out (photo 18) together with a good ground maintenance storage shed. Outside the clubhouse is a fine, well built footbridge which gives access

191

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19

22

This display board indicates that the club had a renowned member of the model engineering world.

The splendid pedestrian footbridge.

23

20

Lots of conversations going on around the steaming bays.

21

An aerial view of the steaming bays from the footbridge. to the inner grassed picnic area (photos 19, 20 and 21). There is also another sturdy, low profile carriage storage shed which blends in well with the area.

The railway itself is called the Henry Greenly Memorial Railway because quite a number of years ago the local area of Durrington was being surveyed for a new four track railway bridge and the surveyor was none other than Henry Greenly. The area included the current site of the club and knowing his railway

192

connections, it was considered to be a respectful action to name the railway after him (photo 22).

One other notable feature of the area outside the clubhouse is the genuine LBSC Railway station lamp. It was given to the club by British Railways and members erected it on site. The lamp itself has been completely rebuilt by members by referencing an existing lamp located on the Watercress Railway in Hampshire as the master. A nice little story emerged from this exercise:

Two members adjusting an original LBSCR lamppost and lamp on site at Field Place. when trying to find a suitable mantle for the newly restored gas lamp, a club member, who was on his honeymoon in America, found a source of the mantles there and promptly bought a supply. On his return the new mantle was duly fitted and, when lit, it gives that lovely soft, yellow glow that such lamps usually emit. The irony is that when the acquisition of the suitable mantle was discussed at the club it transpired that

the same item could be bought from a small shop just down the road in Littlehampton (photo 23).

It only remains for me to thank Geoff Bashall and all the members at Worthing who made my wife and me so welcome at their club. It was a real pleasure to meet you all and to enjoy your wonderful railway. Thank you.

ME

Model Engineer 24 January 2025

A Tandem Compound Mill Engine PART 12

David Thomas builds Arnold Throp’s model of a Corliss mill engine.

Continued from p.131 M.E.4760 January 10

he original drawings show the cladding sheets and pieces of brass angle needed for covering cylinders with square corners.

Having chosen to make the high pressure cylinder with rounded top corners I needed to do a bit of design work for

T

the cladding and the corner angles. A good way to start on that was to look at examples of original engines and see what was done when the engines were being built. In two visits to the UK, I managed to get to the Anson Engine Museum and the Bolton Steam Museum

of the Northern Mill Engine Society where it is possible to get close to original engines and talk to knowledgeable people. At the Anson Museum (on a non-steaming day) I was allowed close enough to take pictures of the Stott engine (photo 192) and in Bolton I

192

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Cylinder of the Stott engine at the Anson Engine Museum. Author’s photograph.

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193

193

194

Making angle stock from square brass tube – first cut…

The J. & W. McNaught tandem compound in the Bolton Steam Museum. Author’s photograph. builders. Both show how the cladding and angles were fixed, and they also show two ways of finishing the edges of the cladding. In the Stott engine some things (e.g. valve bonnets) that protrude through the cladding have a small rebate in the back surface and the edges of the cladding are covered by that; other parts (e.g. cylinder covers) have external cover strips applied.

In the McNaught, cover strips have been used everywhere to hide the edges. On the original drawings for the model there is

could photograph around the J. & W. McNaught tandem compound (photo 193). The latter engine is a good example of the sort of engine on which Arnold Throp based the original model. He described this as being ‘…representative of the smaller types which were made in great numbers from about 1860 onwards in this country for driving textile mills…’ (ref 11).

Photographs 192 and 193 provide a lot of useful details of how things were done in the real world of the engine

Fig 31

Ø1 .5 6

1.813

Ø0 .8

Ø1 .56

3

95

3

Bend this region to 0.5in radius

7.986

Flattened Top And Ends

5

5

.7 Ø0

.7 Ø0

0.54

Mat’l: 0.01in steel (blued if available) or similar brass sheet

.5 r0

2.656

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09

. Ø1

3 81

. Ø0

3 81

. Ø0

Outer Side

Valve Gear Side

Outlines of the cladding parts with the one for the top and side flattened.

194

195

…and second cut. a note for the cladding sheets that reads: ‘Trim where needed to clear cylinder covers’ which is probably the simplest option if you think you can manage it neatly. I chose to copy part of the Stott method and turned in small rebates deep enough to accommodate cladding about 0.01 inch thick. The drawings in fig 31 are dimensioned for this method with the holes 1/16 inch smaller in diameter than the outsides of the various covers. The curved angles in the real engines were made as separate small pieces but there was nothing to show how they had been made.

There are now two rather different ways for the story to go: the way I did it and the way I probably should have done it!

I’ll start by describing what was done. It seemed reasonable to assume that small brass angle

of the correct appearance would be easy to buy in but when I went to look, any small angle that was available looked like it had been folded from sheet and had very curved corners that didn’t look the part at all. What I did find was 3/16 inch square x 0.014 inch brass tube from K&S Metals that had nice sharp corners and could be seen as four lengths of 3/32 inch angle joined edge to edge.

All that had to be done was to cut them apart. This required a fixture for holding the tube while a fine slitting saw went to work. This fixture was a 3/16 x 3/32 inch groove on one corner of a lump of stock from the hoard (photo 194) and the tube was Superglued into this and attacked with a 0.01 inch slitting saw which was a tool I hadn’t used at all until now.

This ignorance led me to use

Model Engineer 24 January 2025

0.375

Ø0.25

1.687

0 0

0.75

0.375

0.5

0.543

2

1.499 0.25

0.75

1.293

Fig 32

0.668

MILL ENGINE

0.5

1.75 Ø0.375 1.375 1.219

0.875

0.375 sq.

2 off Ø0.25 ream

0.095

2.5

Lever

0.5

Ø0.375 0.188 Ø0.25 Ø0.25

Loose Spindle

Anchor Post 1/4 BSB or

2

0

any fine thread

Base

Ø0.25

25 0.0 04 0.1

Fulcrum Pin 0.28

0.375

Ø0.25

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0.188 A

2

0.016 0.079

Fixed Former

Ø1 .0

5 .2 Ø0

Rolling Former

0.014 Adjust slot dimensions to suit angle

0.093 Detail A

0.016

Bending Jig For Brass Angle

Bending jig for small angle stock.

196

Cutting out the cladding plates. the saw ‘as is’ in the holder but it tended to wander off the line so some thick washers were adapted to keep the saw where

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it should be. Photograph 195 shows one of the second cuts dividing a piece of channel section into angles.

With the angles to hand I went looking for thin steel sheet, ideally some that had been blued already. Blued steel I couldn’t find anywhere and its probably a very long time indeed since such was made so shim stock, which comes with a very nice finish, was the next choice. Ten thou sounded about right as it wouldn’t occupy much space behind the angle and there might even be room for some thin card to provide a bit of thermal insulation (note the lack of any calculation). Where I am, larger pieces of 0.01 inch shim are only available nicely curled up in a tube, but the finish is nice - and all (!) I had to do now was get it flat and turn it blue. The flattening wasn’t that easy but turned out all right,

so templates were printed and the parts cut out (photo 196).

Blueing by heating on a tray of sand in the muffle furnace worked well for small samples but achieving a satisfactory uniform colour on the actual pieces proved impossible and even one bit of sand getting onto the surface left a distinct spot. The simple solution was to use some black gloss enamel, and that looks good.

The next task was to make four ½ inch radius bends in the brass angle and fortunately a design for the necessary tool (and some of the bits) was already to hand. When I was finishing off a 1 inch scale Minnie traction engine I’d made a pipe bender to Derek Brown’s design (ref 12) which I knew worked very well. Figure 32

195

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197

198

Forming the second bend in a piece of cladding angle.

199

200

Both angles finished. The gaps visible under the angles are to allow for the cladding thickness but are also a bit too wide.

201

12BA brass RH screws in place. The steam lever trunnion in the centre shows how overlapping the fittings over the cladding gives a neat appearance. has the necessary drawings for adapting the tool to bend angle; this could be adapted for other sections by changing the slot in the fixed former.

After annealing, the brass angle could be bent to quite precise angles and in photo 197 a 90 degree bend has been completed with the material obscuring a line marked on

196

Close-up of the angle before bending; note the line marked across the angle to indicate the start of the bend. Quite precise angles and lengths are possible with this bending jig. The black dust is graphite to lubricate the bending.

the base that showed the end position. In photo 198 there is a fine marker line across the material that has been lined up with the point on the fixed former where the bend will start (the black dust is powdered graphite used to lubricate the bending).

Photograph 199 shows the final results and also shows

Tapping 12BA threads into cast iron requires the use of a tapping guide. that I’d overcompensated for the cladding thickness which required the angles to be cut and a small amount removed to fit tightly in the final assembly. In order to screw everything together I had to be able to drill and tap for 12BA screws - something that just wasn’t going to work with any of my existing kit, so a few weeks were spent building a George Thomas Universal Pillar Tool from a Hemingway kit. You can see in photo 200 that I didn’t spend any time on unnecessary details; there are no ball handles for instance.

I broke one drill during the assembly and that was due to getting careless and hitting the edge of the cast iron. I should have made the UPT years ago!

Photograph 201 shows the bits at this stage.

What has also happened before photo 201 was taken is that I abandoned the 3/32 inch angle and went to ¼

inch commercial stuff, crude bending and all. The way that the screw heads go to the edges of the angle shows the folly of trying to use the smaller angle, a 12BA RH screw head has a diameter of 0.09 inch which would hang over both edges. Furthermore, the top diameter of a 12BA thread is 0.051 inch and a clearance hole for this doesn’t leave much from one leg of 3/32 inch! I really should have done this arithmetic before starting work on the cladding. When (if?) I go back and tidy up the model I’ll start with some ¼ inch square tube (to get the nice sharp corners) and make the angle from this. For the cladding sheet something like 0.5mm would be easier to handle and would be supplied flat. I may also explore other ways (e.g. chemical colouring) to try to achieve the colour visible on the cladding in photo 192.

To be continued

REFERENCES Ref 11 Throp, A; A Model Condensing Corliss Engine; Model Engineer Vol 149 No. 3687 20th August 1982 and No. 3689 17th September 1982.

Ref 12 Brown, Derek; Elegant Pipework; Model Engineer’s Workshop, Feb/March 2000, issue No. 64, pp 37-40.

Model Engineer 24 January 2025

Fred – a 5 Inch Gauge Locomotive

A Young Engineer’s Project 2

Introduction Spencer Priddy constructs his first locomotive.

Portsmouth Model Engineering Society

My name is Spencer. I’ve always had a love of trains and modelling and this all started, as with many young people, with Thomas the Tank Engine.

I joined Portsmouth Model Engineering Society (PMES) in 2022 along with my dad.

Since joining I have entered the Federation of Model Engineers Young Engineers competition and this article documents my 2023 entry for which I was one of the winners awarded the Very Highly Commended Certificate at the 2024 AGM (photos 1 and 2).

Model Railway, Boats and Planes on a Budget

After I was given a large number of Model Engineer magazines from the late 1980s to the early 1990s from a fellow society member, I set about reading them over the Christmas school holidays of 2022 - 2023.

1

Spencer receives his award from the Federation of Model Engineering Societies – (L to R): Bob Polley (Chairman, FMES), Matthew Thomas (Polly), Spencer, Julia Thomas (Polly).

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The article which inspired Spencer.

Spencer with his newly awarded certificate.

The project

3

I found an article about a 5 inch gauge battery locomotive in a 1989 issue. It was from reading these Model Engineer magazines that the next project was established - a 5 inch gauge battery locomotive that I was going to try and build as much from scratch as possible.

At the same time I wanted to build the locomotive for a cost below £500.

I started research over the Christmas holidays, reading a Model Engineer article ‘Going Electric’ by Rex Nicholls. This article was good and gave me an understanding of how and where to start scratch building.

From here I went on to doing further research on the internet and found another article in a Model Engineer magazine which I didn’t have a copy of.

After a little search on the Internet I found the required

copies on eBay, so they were purchased. These articles were about a locomotive build Fred (photo 3). I preferred this build article for my first build, as I believed this kind of design could be built for below £500.

My design of Fred I made the decision this would be the locomotive to build but with a few changes, for example my Fred would have six wheels, two motors and a different body shape. Other than this I would be using steel to make the frames and driving the wheels by chain from the motor just like the articles I researched.

The reason for my changes are as follows. The first change was that I chose to make Fred with six wheels instead of four. After reviewing my ideas and the articles with other club members at my monthly meetings at PMES, they suggested that six

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4

6

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The chassis is well on its way.

Drilling an axlebox.

5

10

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Squaring off the end.

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Fixing the motor suspension.

Measuring up for axlebox fixings.

A completed axlebox. wheels would be better than four, giving more stability to the locomotive around the PMES track. The reason for the second change to have two motors is due to the availability of suitable motors and providing a better power delivery to the wheels. This idea follows the practice used in most modern built locomotives. The final change was to the body - this was in order to make Fred look distinct from my other locomotive Comet.

After working out the correct the gear ratio to achieve 7mph the locomotive was to be built to the following specification: Name: Fred Power Type: Battery electric.

Transmission: Direct drive, chain and sprocket - motor sprocket 8 teeth, wheel sprocket 29 teeth.

Motors: 250W x 2.

Wheel Diameter: 3½ inch over the flange.

Length: 770mm.

Width: 240mm.

Height: 435mm.

The build The build of Fred started in 2023 with the purchase of six

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wheels, axles and hangers from SMR Engineering, with the hangers receiving some modifications. These parts were then cleaned up, sharp edges removed and assembled. The parts went together well with only minor filing required to the edges (photos 4 and 5). I made new front covers from thicker 6mm steel to give more area for the springs to sit on. I also drilled a hole in the front cover to help with oiling and changed the machine screws for hex bolts to give a more realistic look.

For the next part of the build I moved on to making the chassis of the locomotive. For this I used the articles from Model Engineer magazine as a guide to the size of the frames, substituting materials as required due to changes made by me and availability. 25mm equal angle was used to make the main frames. I cleaned up the ends, checked for square and marked the centre (photos 6, 7 and 8). All materials were cut by hand with a hacksaw.

The frames were marked out, drilled and assembled with 6mm bolts used to attach the hangers to the frames.

Once the test fit proved to be successful, Loctite was

Motor mounting. used on the bolts attaching the hangers to the frames only. The tools I used were a square, steel rule, vernier, centre punch, hammer, drills, pillar drill, spanners and socket with ratchet. Next I went on to make the frame braces and motor mounts. 4mm bolts were used to attach the braces to the frames. These were also Loctited as well as the 6mm bolts for the motor mounts (photos 9 and 10).

Next I drilled out the centres of my sprockets to fit the motor shafts and axles (photo 36).

I then drilled and tapped M4 holes for grub screws - these

grub screws would help in securing the sprockets on to the motor shafts and axles.

Once the sprockets were fitted to the axles, the wheels were then fitted and Loctite used to retain the wheels in place. The chains were then fitted and power from a 12V battery was supplied to test the motors, the direction of rotation and chain tension (photos 11 and 12).

Next I made a start on the body, first making a mock-up out of card to see if everything would fit and making the final decision on how Fred would look (photo 13). I decided on something like a Class 14 shape (there’s another change from the original Fred).

The body would go on to be made from 6mm MDF. This

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Motor and drive chain installed.

Model Engineer 24 January 2025

FRED

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Material

Source

Cost

Wheels and axles (x6)

SMR Engineering

£41.55

Axle boxes/W irons (x6)

SMR Engineering

£90

Gears and chain

eBay

£46.86

Right angle steel 25mm x 25mm x 2m

eBay

£20

Steel bar 35mm 6mm x 2m

eBay

£26

Motors x2

eBay

£50

Steel plate x4

eBay

£27.40

6mm Bolts x 34

B&Q

£12.32

4mm Bolts x 65

The Range

£9.25

Grub Screws

eBay

£4.50

Spacers 8 x 15mm (x8)

eBay

£13.28

Body 6mm MDF (offcut)

B&Q

£6

Balsa wood

From stock

Glue, wood (PVA) and super glue

From stock

Controller 24V 100A PWM

eBay

£18.74

Wiring , connectors, switches

eBay

£26.08

Paint

Marine super store

£29.95

A complete chassis.

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Bodywork mock-up.

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Materials List

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Beginning the wiring job.

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Marking out the MDF for the bodywork.

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The completed bodywork.

www.model-engineer.co.uk

The hand controller.

The drive system in place.

was a bargain find in the B&Q off cuts bin and only cost £6. This was marked out and cut by hand, the locomotive chassis being used as a jig to build the body up on to, ensuring each part cut fitted before moving on to the next piece. This was glued and

pinned together and sanded to shape (photos 14 and 15).

Next I completed the wiring to my diagram and parts list, making my own hand remote for the controller (photos 16, 17 and 18). I successfully test ran the locomotive in April on one of the track

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maintenance mornings in the Easter holidays (photo 19). No adjustments were needed with Fred performing well, pulling me and two adults at a speed of 8mph on the straight part of the track.

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Summary Fred was painted a light blue with a yellow front ready for public running over the summer this year with further detail painting planned for over the winter ready for the start of the new running season next year.

The build of Fred started in February 2023 after completing hours of research reading past Model Engineer magazines.

Fred has proven to run very well and has now done a number of public running days over the summer of 2024 (driven by Dad due to my age – photo 20) and has clocked up 45.83 miles of trouble free running. Fred was built by myself with just a few hand tools and a pillar drill - no lathe or mill was used. The work was completed under the supervision of my dad along with many club members providing endless support and advice. I also incorporated a few club members’ suggestions into the design of the locomotive. I was also able to keep to my target cost of a sub £500 locomotive - the total cost of Fred was £421.93p.

I hope this project goes on to inspire others to build their own electric locomotives from scratch. I feel I have proved you don’t need expensive tools or a big workshop or even deep pockets to enjoy this hobby or build a locomotive for public running.

First test drive.

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What’s next I’ve planned and started my next project for this year’s young engineers’ competition, researching the books by Tubal Cain and planning to overhaul a LBSC Maisie in the future with many more projects to follow.

Further updates and projects can be followed on the following Facebook pages: Portsmouth Model Engineering Society

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Spencer’s dad driving Fred. www.facebook.com/share/ MG3EXhCJzyzPMqCZ Model Railway, Boats & Planes on a Budget

www.facebook.com/ share/93oMucPz3Dup9iD9 ME

Model Engineer 24 January 2025