From Firth Came Forth… Compounding & Valve Gear?

[Martin Johnson 1]

On Martin Johnson 1 Said:

I really find SOD & Michael G’s approach rather a put down.  I am also concerned about earlier disparaging remarks about concurrent design and build.

…
Martin

I’m not intending to put anyone down.  It’s clear that from the questions asked that Nigel’s endeavour isn’t going well, so the question becomes ‘why not?’ as a precursor to suggesting alternatives.   Rather as a doctor tries to find out what’s making the patient ill before deciding the treatment.

I don’t think there’s anything wrong with Nigel’s commitment or workshop skills.  But it feels to me as if he’s continually getting stuck on problem solving, part of design, which is a different skill set.   Learning a bit about the design process might get him out of the mire.

In my professional life ‘lack of design knowledge’ was a major cause of delay and malfunction, and it was painfully obvious the cost of  by botched design grows exponentially with project complexity.   Above a certain level, the engineer cannot wing it – he has to take a disciplined approach.

I cannot agree that concurrent design and build is just about the only way to proceed on such a project!  To me that’s a recipe for failure, and I don’t think that’s quite what Nigel is doing, for example he wants to start with a General Arrangement Drawing, which is one way of pinning down major dimensions, and compatible with my suggestion that the more design that can be done before building starts the better.   It’s a variant of ‘Measure Twice, Cut Once’.   Otherwise, one is liable to end up spending ‘many hours on 2D cad or laying on my back looking at a part finished lorry figuring how in heaven’s name I can get pipe X from A to B while missing all the junk in the way.‘

I submit Nigel doesn’t need to be encouraged to carry on as normal.  He needs practical help: ideas he can apply to unblock the drain.  I’m suggesting alternatives in hope they might improve Nigel’s rate of progress.

Dave

 

[Martin Johnson 1]

On Martin Johnson 1 Said:

I really find SOD & Michael G’s approach rather a put down.  […]

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Well I sincerely hope that Nigel doesn’t share that view !

My reference to Donald Rumsfeld was entirely empathetic … appreciating that there is a ‘matrix’ of known-unknown states is a very important step towards comprehending  a complex situation and navigating one’s way through it.

You are, of course, fully entitled to express your opinion, Martin … but I am entitled to consider that you have utterly and completely grasped the wrong end of the stick !

MichaelG.

[Nigel Graham 2Participant @nigelgraham2]

Don’t worry, Michael & Dave, I don’t share that view (of your advice)!

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Martin –

Thank you for your support, but I think you’ve misjudged the others a bit! They are also trying to help me, which is not easy!

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When I started this project, it would have been unique. I was contemplating a Foden Overtype but those are ten-a-penny. Then the Dorset Year Book 1977 illustrated an article on the industries around the North Dorset town of Gillingham with a photograph of a Hindley steam-wagon, not far from its birthplace in Bourton,  and that decided me.

It took me about three years to find and piece together enough material to start, delayed somewhat by my preliminary drawing (pencil on paper!) looking all wrong. It transpired the dimensions quoted by Commercial Motor magazine were not those of the wagon photographed for the review!

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I made a gigantic mistake right then by trying to build it at 6″-scale and not surprisingly this ground to a halt. Eventually my girlfriend of the time encourage me to start again but at a more sensible scale – and that is what I am doing.

It is to 4″ scale so is about 5ft long chassis frame by 2ft across the platform and bunkers. I narrowed the wheelbase and chassis by a couple of inches so with the upper works lifted off it would fit through the front door of my house at the time! One reason for making those units readily removable, the other being building and servicing access.

Bits of the first version survive. Slices of its boiler shell, a length of seamless mild-steel pipeline tube (this before all the fuss about certificates of conformity), are the new version’s rear wheel tyres. The outer firebox’s top plate, 14″ dia X 3/4″ thick, became a bell-chuck for machining the new wheels on a 6″ IXL / Ehrlich lathe I owned at the time. The chassis rails and cross-members, in 3″ X 1″ X 1/8″ aluminium-alloy channel, are now part of a ramp for winching Edition Two up onto an assembly-bench.

Progress on the 4″ version was reasonable at first, and I used the IXL lathe to bore the cylinders in a solid rectangular block of cast-iron, and machine the parts of the boiler I started making.

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It was a proud moment when I wheeled the bare chassis, still with no steering, out of the front door to photograph it in Summer evening sunshine, in a small side-road. The Council had even obligingly painted two yellow lines along the gutter to provide scale.

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A year or so and a workshop (with house) move later, and I hit various problems, not least mental ones – depression mainly. Then I discovered it was no longer unique, as a member of Taunton MES was near to completing his own Hindley “Light Delivery Van” as the original was designated. I did not meet its builder but did view the model, at one of the excellent annual exhibitions that his club ran for a few years. I know model-engineering is not competitive except at rather rarified national exhibition levels, but it hit a bad spot with a major failure elsewhere, and I lost a lot of confidence and interest; though I still took part in my own M.E. society’s activities.

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Western Steam had a sales stand at one Taunton show. I had doubts about making my own boiler after I saw some calamity-displays at Alex. Palace, showing what can go wrong. So I ordered a boiler from WS, using my outline drawing based on Hindley’s patent-specification for it; and collected it from the next year’s Taunton exhibition.   (The abandoned boiler’s components are still up in the loft, for possibly finishing one day to see if I can.)

Since then the project has staggered along through yet another workshop move – also complete with a house – other interests, commitments and projects, spells of enthusiasm and less enthusiasm, attempts to learn CAD in the vague hope it would help me design the thing, and many technical difficulties caused by my not thinking sufficiently well ahead….

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One year, coming home from displaying it “Under Construction” at the MSRVS Rally, I detoured to photograph the wagon outside her ancestral home, still there but derelict; now all gone. I could not take her into the yard thanks to fencing and a gravel bund, but partially replicate the old catalogue’s factory-yard photographs, with the still-recognisable buildings in the background. If I can find the photographs, which might be on film (!) I will try to copy one for this forum.

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I have also heard of someone else with one these beasts, but I do not know if a second model, or that Taunton one in new ownership.

There is also a full-size replica, which I saw at a very early stage of building.

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I spent the first part of this evening at my club, on ground-level track maintenance; but on return, before coming on here, I created an Alibre Drawing from the Part version of the wagon’s compound cylinder block to start assessing how to modify it. This is so I can sketch possible alterations by rule and pencil on paper prints before formalising them in Alibre as new workshop drawings.

….

That evening I photographed the rolling chassis out in the street, a young boy passing by asked me what it was.

I had to think quickly of an intelligent reply comprehensible to (I judged) an eight-year-old. “It will be a model of an old-fashioned type of lorry”, I said.

“Cor!”, he exclaimed, “I wish I could make one!”

“Maybe you will, one day”.

He’d be in his twenties, now. I wonder if he knows a File, Second-cut from a File, 1Mb.

[Michael GilliganParticipant @michaelgilligan61133]

Nigel

Thanks to the wonders of t’internet … I have just found this:

https://drive.google.com/file/d/1YB28Sqdy_-N6oWbYhjEnoV4cDrDkMqhw/view

The rather delightful Hindley waggon is pictured on a p.21 in quite a good scan.

… You may have it already, but I offer it as encouragement.

MichaelG.

[Nigel Graham 2Participant @nigelgraham2]

Thankyou Michael.

More than having that photograph already..

I forget if I bought my copy of the book all those years ago, or if it was a Christmas present, but….

 ….. that book, article and photograph was my source for the whole project!

🙂

 

The wagon picture is on magazine-page 21 (pdf p. 23) but on p.18 (21) is a distant photograph of the Hindley factory, dominated by its huge water-wheel.

It is an intriguing photograph socially, starting with the intended purpose of the coal (I wonder how much fell off during the Carnival procession?).

The owner, Mr. Maloney, clearly did well, with his watch-chain and waistcoat highlighting a slight physical corporation suggesting the success of his business corporation.  The two characters in their Sunday Best, standing on the load, but were probably Maloney employees, perhaps in managerial or supervisory roles. The wagon’s driver and his mate have that rather emaciated look typical of manual workers of the time; the chap at the back certainly does, and he looks as if he is very unsure he should even be photographed in such august company.

‘

The coal was to probably “given away” to the local poor. This was still the era of the work-house, places so dreadful people sought their shelter only in really desperate circumstances; and pensions were sparse and rare. So there must have been many scraping a living in semi-derelict cottages, sometimes helped by charity – such as this lorry-load of coal.

That wagon is of the pattern designated “Light Delivery Van” by its builders, and rated at 2-3 ton capacity. So there is perhaps 2 tons of coal on board. Judging by the size of the lumps, that coal has probably not travelled far, and indeed the nearest collieries were around Radstock and Frome, about 30-40 miles from Gillingham.

The coal would have arrived by train, probably on the Somerset & Dorset Joint Railway with the last part from Templecombe Junction to Gillingham Station on enemy rails – those of the London & South Western Railway’s London – Exeter line. The former Southern route is still busy. The SDJR is long gone, killed as much by inter-Regional railway management “politics” as economics, and given a swan-song by Flanders & Swan (The Slow Train To Blandford Forum).

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What identifies this lorry as the Light Delivery Van is the chain-drive.

That Y-shaped motion-plate seems of different shape on every picture!

The brake-shoe is seen bearing against the front of the wheel but on other examples, it is pulled onto the rear.

Just visible in the middle of the cab, behind the brake handle is a tall loop of pipe I think part of the compound / simple system, but it can’t have done the steam much good.

The chimney’s polished capuchon is not usual either. Usually the plain stove-pipe was finished with a half-round bead, and all painted one colour: as I have copied.

The side-lamps are standard but the headlamp and its rather crude wooden bracket seem owner-fitted.

The ‘FX” registration denotes Dorset County Council.

 

The bigger “Standard” wagon and its heavier-duty “Colonial” form were under-types with the engine geared directly to the rear axle. One review photograph of a “Standard” shows something just in front of the rear off-side wheel, which I think was the gear-lever. If so, the driver would have to dismount to change gear!

 

Charles Maloney must have been feeling kind to his staff when he ordered that wagon. The catalogue and other contemporary photographs suggests a canopy was an optional-extra, as only a few others were photographed so fitted. Even Pickfords, who bought a Standard fleet for furniture-bumping, managed only a token pram-type canopy screwed to the front of the lift-van body. Otherwise the crew had no weather protection at all. Still, neither did carters and most traction-engine drivers, so why should steam-wagon crews need molly-coddling?

I am fitting my specimen with a canopy approximately to that style. It looks a bit bare without!

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Having mentioned the Somerset Coal Field, not far from Radstock is the village of Chewton Mendip, home to a contemporary engineering company, that of C.W. Harris. This bought a Hindley wagon, and there is a photograph of it carrying a large drum, probably a boiler.

Then Harris produced its own steam-wagon, labelled the “Mendip”. It looks so like the Hindley it begs the question of whether a blatant copy or licensed badge-engineering. Hindley could not have patented the wagon but it did patent the boiler – though how much protection that would give the whole vehicle I cannot say. Subsequently, Harris moved into making motor-cars instead, marketed as the “Mendip”.

‘

Hindley seems to have been looking at the burgeoning petrol engine market too, before the firm collapsed c.1919. It already made gas-engines for industrial plant, and it patented a way of casting water-jacketed cylinders to avoid contraction-cracking, perhaps a common problem to the fledgling industry. The patent was for corrugating the water-walls to absorb the strains, rather as cast flywheels often had curved spokes.

It also patented a supposedly shock-absorbing steam-wagon wheel. The novelty was hardly that: simply a deep wooden rim between the wheel plates and the smooth steel tyre. I have not seen a photograph of a wagon so fitted. Most had the all-steel wheels as in that DYB photograph, though artillery or Bauley-pattern wheels could be ordered. Nowt for it then but to fit my model with the Hindley Patent wheels!

Oh – how do you fit a steel tyre to such a wheel in miniature (12″ rear, 10″ front)? Shrink-fit of course: half an hour in the oven at Gas Mark 9, and a big hammer.

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The present-day, full-size replica of this wagon was built to commission by Richard Vincent, suitably not far from Gillingham and Bourton.

…..

How to distinguish Dorset’s Gillingham from the Kent one? Hard and soft ‘G’ respectively. Easy to remember: as a Sherborne-native friend said about it, we’re harder in Dorset!

 

[Nigel Graham 2]

On Nigel Graham 2 Said:

 ….. that book, article and photograph was my source for the whole project!

🙂

[…]

Yes, I did realise that, Nigel … but I thought it worth sharing the PDF for two reasons

1. not everyone following this topic has necessarily seen the photo
2. you now have a digital copy of the image available, which [as you have recently  learned] could be used to doodle-upon in Alibre.

Thanks for sharing the additional notes.

MichaelG.

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P.S. __ I have already screen-grabbed the photo in PNG format, if that would help.

 

 

[Nigel Graham 2Participant @nigelgraham2]

Thankyou!

I knew few would have seen the photograph, and that is the only place I have seen it. Though the inspiration, the ones I used for the project are mainly trade-magazine and manufacturers’ publicity images.

I was in fact contemplating scanning the photograph in my copy of the book for use here, but trying to obtain a clear full-width scan on an ordinary home-type printer/copier would risk damaging the book by over-flexing it. I think it is still in copyright anyway.

The scan you used was probably done professionally and may even have been by the Society of Dorset Men, the annual’s publishers.

 

This link reveals a photo of a 1905-built Hindley “Standard” undertype (the smaller LDV was introduced in 1908), 5-ton capacity; in its first ownership before being sold to C.W Harris, its last recorded owner.

https://chewtonmendiphistory.wordpress.com/wp-content/uploads/2012/08/steam-lorry.jpg

 

 

 

[Michael GilliganParticipant @michaelgilligan61133]

I have just sent you a Personal Message, Nigel.

MichaelG.

[duncan webster 1Participant @duncanwebster1]

Just a suggestion which might be impossible, but here goes. It might save a lot of heartache if a Stuart Turner design engine were grafted in. At least then Nigel would know the engine would work without endless rework

[Martin Johnson 1Participant @martinjohnson1]

Dave, Michael,

Before I posted regarding my interpretation of your posts, I waited a full day and considered very carefully my response.  I still read them as suggesting the OP should build a published design because “It’s design skills Nigel is missing………” and by implication from Donald Rumsfeld “the OP doesn’t know what he doesn’t know”.  If that is how this forum operates, I look forward to the imminent demise of the hobby.  However if that was not the intention and Nigel has taken no offence, then I am glad to hear it and we’ll let the subject drop.

However, I still take exception to the various comments about concurrent design.  There seems to be an assumption that if you noodle away on 3D cad for long enough (and many of us don’t have that long!) you can do anything – not true even in industry.  Steam lorries have very particular problems because you are modelling a vehicle where the original designer has crammed all the motive power into minimum space to maximise load capacity.  You then have extra problems of fitting in an out of scale driver, plus usually overscale pipework, better braking than the original, modular bodywork, assembly & maintenance without the aid of trained midgets etc..

If you have not designed a scale steam lorry from scratch and then tried to build it then you are not really qualified to comment.

My own experience mirrors the OP’s to an amazing degree even including starting in one scale and finding that a smaller scale is appropriate.  I also made all the patternwork for compound cylinder blocks (insurance!) but never used it in the end.  Try and design what you can, allocate space for the major blocks but sooner or later, you will be laying on your back working in real live 3D wondering how you will fit the details around the big building blocks.  Then back to the drawing board to draw it up and then build it.  Repeat as required.

However, it can all be done.

Martin

[Paul KempParticipant @paulkemp46892]

Well said Martin!  I would also add that working to a published design does not mean there are not poor design decisions incorporated, things that can be improved to improve performance or to bring the published design closer to prototype.  That is without considering the errors in dimensions in the ‘plans’ – I would refrain from calling them drawings as so often there are no tolerances noted and anyone making a 1.5” cylinder with a 1.5” piston as often shown is going to run into trouble when trying to put them together.  With many large projects I have been involved with most of the drawings get amended to an as fitted version as even with the 3d CAD errors quite often go unnoticed until the bloke on the shop floor tries to make or assemble.  Criticising Nigel’s approach is not particularly helpful.

Paul.

[JasonBModerator @jasonb]

One thing that I have noted from Nigles earliest posts is that he wants to build a Hindly Wagon. So sticking a Stuart engine in it is hardly going to go down well as that starts to make it a freelance.

What one do you have in mind Duncan?

Nearest may be the current incarnation of the No 3 but it’s too big a bore and too short a stroke and unlikely to fit between Nigle’s chassis rails or behind the boiler. Then there is the fact it’s built for quite high revs (2000rpm) and a 120 working pressure. It’s also a compound which seems to have gone out of favour. With so many factors against it before we come onto the look which is important to Nigle and making it enclosed then building from scratch as is being done seems the better option.

His GA has all the right bits and from what I can see it will work, there is just some distance between what is on the GA and the final detailing of the various parts.

[Michael GilliganParticipant @michaelgilligan61133]

Martin/Paul

I have no desire to be drawn into a fight … so instead of replying to either of you, I will just quote:

Least said, Soonest mended

Nigel is perfectly aware that my intentions are good.

MichaelG.

[Martin Johnson 1]

On Martin Johnson 1 Said:

Dave, Michael,

… I still read them as suggesting the OP should build a published design because “It’s design skills Nigel is missing………” …

What I actually said was: Swotting isn’t to everyone’s taste. The alternative is to learn from existing designs. Not just by building an example, but studying and understanding how it works, then looking for ways to improve it.

 

There seems to be an assumption that if you noodle away on 3D cad for long enough (and many of us don’t have that long!) you can do anything – not true even in industry.  …

Martin

The assumption that anything can be done by noodling away on CAD is yours Martin.  I don’t believe any such thing; rather I suggested starting the preliminary design on squared paper.

Whenever I identify a skills gap in my workshop, I try to fix it.  Which reminds me, I still can’t cut straight with a hacksaw.

🙁

Dave

[Nigel Graham 2Participant @nigelgraham2]

Martin –

I have seen detail drawings for parts that raise the immediate question, “How the heck do I make that?” The trap is that it is all too easy to draw something that can’t be made.

I’ve heard this is particularly so with CAD but I am not convinced. Rather, I suspect the difficulty comes insufficient practical experience, and I imagine such clangers occurred in the days of elm drawing-boards and 4H pencils. Less often perhaps because the designers were more likely to have completed proper apprenticeships, but even the most experienced can make mistakes.

Indeed, though the drawing-office in one company for whom I worked had sophisticated parallel-motion boards, there were rare instance when as a materials store-keeper cutting blanks, I’d seek out the draughtsman responsible and politely point out, “Won’t that hole fall off the edge?” (Simple measuring or arithmetic errors).

I understand a lot of shambles in major projects are not the unfortunate designers’ fault but by customers not understanding what they want, or changing the specifications in mid-work.

There is a curious human trait that the greater the experience the less the likelihood of spotting a very simple fault cause. Like an locomotive’s exhaust connection gasket with no hole through it. The constructors concerned were all so skilled and experienced they could not have imagined making such a basic mistake, and spent months desperately searching for arcane valve-gear errors. A tiny leak led to the real cause and solution.  Or in another situation, an electronic system was just not working. What had several very educated and skilled, and now very despondent, scientists all missed? A double-sided frequency pass-band filter set to pass no band at all. The pattern of the two switch knobs indicated the mistake.

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Paul –

I agree with your general point about most published model-engineering drawings but we are not making industrial-practice machines with interchangeable components, and cannot all match the finest trade limits of accuracy. So the general practice has always been make each part as well we can and to work with its mating parts as it should; rather than chasing the last decimal point.

Similarly when we design something ourselves, be it a major model-building project or a fairly simple machine-tool attachment; we can only really do so according to our own facilities and level of skill.

With model-engineering we can adopt whatever approach we want, within reason; provided we achieve our aim.

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Jason, Duncan –

Actually I did consider modifying a Stuart-Turner engine!

A friend gave me some surplus castings, I think for a 5A, but I realised they were too large for the scale and boiler.

The Hindley engine is vertical and almost entirely enclosed, although the casing and the cylinder-block are prominent, so disguising a suitable ST engine would have been relatively easy.

Other Stuart designs were all either too large or too small.

I am not after fine-scale details to Gold Medal level, a level I greatly admire and respect though not one I could reach. Apart from the vague source information available, the original vehicles were rarely exactly alike, judging by the photographs. My aim is sensible fidelity to the spirit of the extinct Edwardian vehicle’s line, rather than absolute replica of one specific original.

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I recall admiring a 3″ or 4″ scale traction-engine at one of the major shows. Oily soot in the chimney, patinated pipework, scuffed wheels, oil stains, coal-dust and that lovely satin sheen on properly-machined and regularly-cleaned exposed steel: a well-built, well-used and well-loved engine.

Then I overheard the man next to me say to his pal, “That bit’s wrong!” – one of the smaller components.

Maybe, strictly, to original design – maybe reflecting a modification in the full-size originals, or the factory using remaining stocks from a previous product? Importantly though, no obvious fault, mis-match, anachronism or poor workmanship.

Of course, I said nothing. Instead I thought, “Oh aye? Which one’s your exhibit?”

 

[duncan webster 1Participant @duncanwebster1]

Stuart #4 is 1.5 bore * 1. 25 stroke, #1 is 2 bore and stroke, so a hybrid twin version would give all the relevant scantlings to make a successful engine. Draw it out fully before cutting serious metal. I’d use 2D CAD because it’s what I’m used to, but #2 son would do it a lot faster in 3D, and make sure that you didn’t have clashes a lot more easily than in 2D.

Make it aesthetically how you like, at least you will have something that runs, it must be soul destroying to spend weeks making something only to find it’s wrong and has to be consigned to the bin.

[JasonBModerator @jasonb]

So you are now suggesting using bits of various Stuart designs and using those to draw up an engine. That is basically what Nigel has already tried to do but it is the drawing up that has been his problem for the last 4 to 5 years that he has been posting here.

He has posted his 2D GA of the engine and that is basically what he has done but as I said there is some way between that and actual parts that can be made.

[Nigel Graham 2Participant @nigelgraham2]

4 to 5 years? As long as that? Good grief?

Actually my previous questions were about other aspects of the vehicle, such as a simple one about steering. Many of the responses left the road and ploughed into the shrubbery of steering-geometry. I’d already made all that, it works,  and it was not what I asked!

I did start by trying to design the engine from first principles, using “full-size” text-books, but realised I am better working to model-engineering literature, and adapting proven miniature engine designs. The detail shapes of the bits of steel are not critical: what matters are things like the cylinder and valve dimensions, and centre distances.

All I asked recently was whether superheating would be effective on this particular engine, and if simple would be better than compound cylinders… To which the consensus appears to be “yes” and “yes”, but put the regulator downstream of the superheater – and one response accidentally suggested how I can do that.

[Martin Johnson 1Participant @martinjohnson1]

Nigel asked how to avoid designing parts that cannot be made.  There is no single answer apart from experience, but the following might help:

Always think as soon as you specify any feature (hole, shaft, bracket, bearing block etc. ) on a part – how will this be produced.  From that follows “Is there enough room to get the tool plus chuck or whatever in there?”  Classic example of that one is a spoked flywheel specified with a grub screw between the spokes to fix onto the shaft – impossible.  However, an inclined grub screw hole so that the drill can go in from one side is easy.  Another one I saw in ME magazine was a whistle with a female O ring groove to seal the valve stem.  The valve stem was 5 dia, with a 2 dia O ring groove, which at very best would require a boring tool with no more than 3mm shank – too fragile to cut a 2mm groove.  However, it’s easy if you retain the O ring with a separate part threaded in.

Other mental questioning can include: How will this casting be moulded, so how will I design the pattern?  What sequence will the machining be done in?  How will I align the part for a second operation?  How will I hold the part while getting access to whatever to do the operation?

In short, if you cannot “walk through” the full production sequence in your head the design is not fit to be released.  In extreme cases, you will need to be checking the “cube” of your milling machine or “cylinder” on your lathe to ensure the part will fit – and don’t forget that drill lengths, chuck lengths and so on all take up space in the cube or cylinder.  In industry, this process can be a lengthy to and fro between design and production departments before an acceptable solution is arrived at which won’t bust the budget.

The same applies to assembly – can you mentally walk through how it will be assembled and check that there is room for a spanner/screwdriver/whatever?  Example on your proposed engine layout – there are two sets of glands (I think) to keep and steam in the cylinder and oil in the crankcase.  Inevitably quite close together in a cramped space.  Can you get in there with a suitable spanner?  Can you pull back the gland follower enough to get a turn of packing in?  Can you get at least 1/12 turn on the spanner?  If not, do you need a gland nut style gland and some sort of C spanner?

Other topics to think through are drainage (is there a drain valve at the low point, does condensate need to be flushed out?), filling (can you get in to fill it with oil/water/ etc?).  Locking of fasteners – things like big end bolts and mains should really be locked against vibration – can you get a lock nut or split cotters in?  If not what other means would be acceptable?  Is loctite going to stand up in an oily hot vibrating environment?

Hoping that helps,

Martin

[Nigel Graham 2Participant @nigelgraham2]

Thankyou Martin –

I do indeed try to consider how to make anything while designing it.

One effect is endeavouring to minimise “spaghetti engineering” -just because it’s a road vehicle doesn’t mean it has to follow the modern car principle of taking the thing half to bits to change a simple lamp. So for example the superstructure is made easy to remove and re-fit for access to the gubbins, and has no fittings or plumbing attached to it.

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There are four glands on the cylinders -two each piston-rods and valve-spindles – and yes, their accessibility will be a headache because the engine is enclosed. The large apertures in the case to reach them, when scaled down to a third of their size, will give quite limited access, so I will need use slotted, radially-drilled or octagonal, union-type gland-nuts. Certainly not studs and nuts.

Access to the rest, as prototype: “quickly detachable light covers” – to quote the manufacturers’ advertisements. I will probably have to fit the base with a removable cover too, to facilitate access to the big-ends, etc. (“split cotters”? Wossat? I can use split-pins but “Nyloc” nuts would probably be perfectly happy there, a long way from any significant heat – and invisible.)

.

Now, I did make the crankshaft end too short for a pair of sliding gears, but I may turn this to advantage by making the 2-speed transmission as a separate unit with a suitable coupling to the crankshaft. That gives me the opportunity to arrange the engine to be removable without disturbing the gears and drive-chain.

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Drain-plugs? Three: one in the engine-case (not really a “sump” in i.c. engine style) and one in the water-tank. The third in a T-piece below the exhaust connection to the blast-pipe, with two functions. The exhaust pipe forms a big U-bend about five inches deep between the engine outlet and the blast-nozzle, so I want to be able to drain condensate from it. The second function is to allow using a steam-raising blower that squirts air up the chimney rather than sucking sooty gases through itself.

…

What else to think of?

The biggest problem is me – as driver! I am not very big but still 12-inch to the foot scale, weigh nine stone and would need sit on the lorry to drive it.

My weight is within the load-limit. Nine stone times three-cubed is 1 Ton 10cwt 3qrs, so I am within the theoretical load: the prototypes were rated at 2 – 3 Tons. Though I have yet to find somewhere to have the leaf-springs heat-treated. Or find a way to do that myself.

I have made a fully-planked flat-bed platform, but for static display. I need make a driving-platform with a big hole for my feet, and foot-rests, and these behind the engine, potentially making reaching the controls a bit awkward.  This is a bridge yet to be reached but the sensible approach is experimenting using salvaged wood before making the finished version.

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The canopy is separate again so can be left on for driving, but I need consider access for firing a boiler not designed for easy firing. The “stoking shoot” – more Hindley jargon – is in the top, and on the model opens about fifteen inches above the grate, as a two-inch diameter tube dropping to the roof of the inner firebox some seven inches down.  My thought is to hinge it like a forwards-opening bonnet – another distant bridge.

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So yes – I do try to head off the main snags as I go but it is still very hard!

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That weight conversion: I later verified it by calculator but only after performing it long-hand without a sum-box, slide-rule or abacus, to see if I had learnt any of the Arithmetic I was taught in Primary School over half a century ago before everything went decimal and schools decided even the two-times-table is “Mathematics”.

[Howard LewisParticipant @howardlewis46836]

As a total spectator, I can only adnire Nigel’s courage and patience.

He is trying to make a mechanism, without drawings of the original, only photographs, which are probably relatively small, and cannot be scaled (Photographs may not not even dry without uneven distortions which is why we should never scale a drawing, blueprint or die line.  And the angle may introduce distortions, some of which may not be obvious.).

Also, IF any drawings can be found, they may not be accurate compared to the actual hardware.

It was not unknown for the fitters, or machinists to find either that the drawing dimension was not practical (or was less easy to make than the operator’s easy way) Think about the drawings for the valve rods on locomotives. They might be drawn, but were finally checked in situ and then sent to the blacksmith to be lengthened or shortened by a 1/16″ or more, so not exactly to drawing.

The original builders knew little, if anything, of Reynolds numbers, Hooke’s law, or UTS. (The materials probably weren’t that consistent from batch to batch, anyway) They had to suck it and see, without the aid of a metallurgy laboratory.  What we know today, they had to find out the hard way.

If it wore, or broke, they made it bigger. Often the rule was “1/2″ looks about right, let’s make it 3/4 to be sure”

Nigel is working hard on a difficult project, with little to help him. He is treading a path where almost no one has walked before, and without maps!

So yes, he will find difficulties, of which the photographs will not have made visible. And part way redesigns and remakes will result.

Keep at it! You will succeed eventually.

Howard

[Nigel Graham 2Participant @nigelgraham2]

Thankyou for your encouragement, Howard!

The only way I could make any sense of the overall size of these wagons was by correlating a few leading dimensions such as wheel diameters. I did not treat the ancient photographs as any sort of true-scale images, especially after discovering one trade-magazine review was illustrated by a different specimen.

Other photographs showed assorted detail differences, though the basics were probably all more or less identical.

It is hard to know to what extent early-1900s engineering designers used metallurgy and other scientific methods, but those were developing rapidly. The book I have corresponding closely to Hindley’s era does describe basic strength-tests, but also quotes a “recipe” for a supposedly machine-quality cast-iron by three tonnages of raw metal by ore-field, plus one ton of “Best selected scrap” .

Nevertheless, they were generally a lot less rough-and-ready as you suggest. My small library of ancient reference-books gives a wide range of samples of good engineering practice, showing they did care about their work. After all, metal and its working costs money so a properly-trained Edwardian draughtsman would not have added an extra quarter-inch for luck. Unlike his grandfather whose extra bits of metal were often just “bling” !

Besides, by then a series of major accidents had taught the engineering profession to design and make things as properly as they could. No more making rivet-holes in critical plates by punching. No more the appallingly sloppy work by designer, manufacturers, contractors and the Board of Trade, that together caused the Tay Bridge disaster.

There were commercial imperatives too. Customers did want value for money, and by the 1900s engineers were as concerned with their creations not only working, but working as efficiently as possible. The demise of E.S. Hindley & Sons as a company is a bit vague but losing Pickfords as a major wagon buyer could not have helped. I suspect one factor was that the Hindley “Standard” 5 – 7Ton undertype steam-wagon was already crude, unpleasant to drive, inefficient and obsolescent alongside the contemporary Foden overtypes Pickfords chose as replacements.

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Still, modern vehicle designers are just as prone to minor modifications to baffle us: I have never discovered where Renault has hidden the “Cabin Air Filter” on my car, and every source of information I have found offers its own hiding-place – none right for mine!

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Well, I took another, small step forwards today by further work on a rather involved-looking plate that will be combined boiler-retainer, damper-lever bracket, injector water-valve spindle support and exhaust-pipe clamp bracket… Lots of hacksawing and filing – strange as it may seem, no slower than milling the same shapes, and fuelled by tea and biccies, not expensive electricity.

 

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