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The Yorkshire Steam Railway: All Aboard. series Three


birdseyecircus
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Some definitions of soldering/brazing/welding.

 

Soldering.

A thermal joining process in which molten filler metal is drawn into a capillary gap between two closely fitting surfaces. Soldering takes place at a temperature below 450°C.

 

Soft Solder.

A Tin based alloy filler combined with either Lead, Silver or Copper depending on the application. Melting points range from 180°C - 350°C and require a suitable flux for the solder & base material.

 

Brazing.

A thermal joining process in which molten filler metal is drawn into a capillary gap between two closely fitting surfaces. Brazing takes place at a temperature above 450°C.

 

Silver Brazing.

A Silver based alloy filler combined with Copper along with varying amounts of either (depending on the application) Zinc, Tin or Phosphorous. Melting points range from 600°C - 900°C and require a suitable flux for the solder & base material.

Also referred to as Hard Soldering or Silver Soldering.

 

Braze/Bronze Welding.

A thermal process using a hand torch and filler metal with a lower melting point than the parent metals. This process uses copper based filler metals melting above 850°C and does not rely on capillary action.

 

Regarding torques settings, there should be a predetermined value for a given size in a given material that ultimately specifies the maximum torque applied to a bolted joint. Beyond said value the risk of failure of either nut or bolt is greatly enhanced.

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16 minutes ago, didcot said:

Regarding torques settings, there should be a predetermined value for a given size in a given material that ultimately specifies the maximum torque applied to a bolted joint. Beyond said value the risk of failure of either nut or bolt is greatly enhanced.

 

Years ago I read a memoir by a former officer in Churchill tank regiment. Apparently they had problems caused by over tightening of  bolts  etc.  This was caused by the weekly maintenance instructions which said "tighten all nuts and unions". Eventually they would fail.  They had to alter the wording.  Fortunately this was while they were still in training.

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So I heard mention of Whitworth nuts for the 9F which was designed in the late forties early fifties but probably had design lineage going way back.  Is Whitworth still used in any current industrial activity?

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Jeff

Modern engineering fabrication will almost exclusively use metric coarse fixings, although there is no engineering reason why you couldn't use UNC UNF Whitworth BA etc depending on application. They have been deemed non-preferred in engineering standards so inevitably as demand reduced, manufacturers stopped making them.

 

The problem as I'm sure your aware is that restoring old steam locos requires fixings into existing castings which are ofted tapped whitworth hence stud especially are needed. It's possible to have whitworth screws and nuts made to order so they do cost and in non critical applications stainless metric fixings are readily available, inexpensive and will do the job just as well. My railway has an individual with many contacts which has enabled us to get redundant stock from factory closures so we do ok and I'm sure other railways are in a similar position.

 

The talk of torque wrenches has amused me, technologically a 9F isn't much different from the Rocket, and it's all blacksmithing to a greater or lesser degree, so tightening up the nut with a correctly sized spanner should make it tight enough without stressing the fixing. If it leaks, still loose, tighten it a bit more. Of course materials technology wasn't so well understood in times past so often engineering was over engineered to compensate, 1/2" didn't work last time, we'd better use 5/8", which is of course why so many locomotives, bridges and a good deal of other Victorian/Edwardian engineering still exists which rather neatly takes us back to the NYMR.

Regards

Martin

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45 minutes ago, Martin Shaw said:

Jeff

 

 

The talk of torque wrenches has amused me, technologically a 9F isn't much different from the Rocket, and it's all blacksmithing to a greater or lesser degree, so tightening up the nut with a correctly sized spanner should make it tight enough without stressing the fixing. If it leaks, still loose, tighten it a bit more. Of course materials technology wasn't so well understood in times past so often engineering was over engineered to compensate, 1/2" didn't work last time, we'd better use 5/8", which is of course why so many locomotives, bridges and a good deal of other Victorian/Edwardian engineering still exists which rather neatly takes us back to the NYMR.

Regards

Martin

Even motor vehicles until technology started to become involved were no different.

1950/60s UK cars went perfectly well using UNC/UNF (Ford) Whitworth/BSF (others) and a big spanner!

The only time you needed to go a little lighter was on alloy parts, which were much more easily damaged (cracked or thread stripped)

These days working without a torque wrench is a definite no-no.

Edited by melmerby
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I can give you three oddities when it comes to thread size:-

 

Some if not all US designed cars have used metric threads going back many many years, maybe as far back as mid century.

 

The RB199 engine for the now retired Tornado aircraft was designed in metric units but used UNJF threads.

 

In the early eighties I was working on a project in the UK for a Swiss company.  We used metric pipe threads only to be told that the Swiss company preferred BSP threads.....

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Thread forms and sizes are undoubtedly complex, and that's just the well known ones. As an aside, it is generally understood that the US uses imperial measurement. Last summer we were in a hotel for a few days and I met a retired man from Chicago, so I would guess well into his sixties, who it transpired had been a mechanical engineer, so we discussed engineering measurement, as you do. It turned out that he had worked with metric measurement for the whole of his working life and his opinion was that the majority of US technology industries that looked for or had any export trade would be similar. He also suggested that in the developed world, whatever that may mean, apart from the US, only the UK had a significant body of opinion that so misunderstood measurement and number systems that they thought imperial was better. I could only agree with that, so we had  another pint.

Martin

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18 minutes ago, Martin Shaw said:

Thread forms and sizes are undoubtedly complex, and that's just the well known ones. As an aside, it is generally understood that the US uses imperial measurement. Last summer we were in a hotel for a few days and I met a retired man from Chicago, so I would guess well into his sixties, who it transpired had been a mechanical engineer, so we discussed engineering measurement, as you do. It turned out that he had worked with metric measurement for the whole of his working life and his opinion was that the majority of US technology industries that looked for or had any export trade would be similar. He also suggested that in the developed world, whatever that may mean, apart from the US, only the UK had a significant body of opinion that so misunderstood measurement and number systems that they thought imperial was better. I could only agree with that, so we had  another pint.

Martin

Interesting observation but not I think wholly accurate.

I worked on Hewlett Packard electronic equipment for a fair while  (up to the 1990s) and I can assure you they did not use metric, neither did Tektronix, Fluke and many others, they were entirely to US standards, even though some of the equipment was designed especially for the UK and had no US equivalent.

These days many Chinese electronic products use US threads, presumably because they are aimed mainly at the US market.

Computers are a good example, generally all US threads.

 

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3 hours ago, Martin Shaw said:

Jeff

Modern engineering fabrication will almost exclusively use metric coarse fixings, although there is no engineering reason why you couldn't use UNC UNF Whitworth BA etc depending on application. They have been deemed non-preferred in engineering standards so inevitably as demand reduced, manufacturers stopped making them.

 

The problem as I'm sure your aware is that restoring old steam locos requires fixings into existing castings which are ofted tapped whitworth hence stud especially are needed. It's possible to have whitworth screws and nuts made to order so they do cost and in non critical applications stainless metric fixings are readily available, inexpensive and will do the job just as well. My railway has an individual with many contacts which has enabled us to get redundant stock from factory closures so we do ok and I'm sure other railways are in a similar position.

 

 

My father was a fitter/turner (although he spent most

of his working life in a foundry, but that's another story).

He bought a small lathe and spent a lot of his spare time

making parts on it. His particular love was cutting screw threads.

He'd always been a motorcycle enthusiast, and after mum died,

he joined the local section of the Vintage Motor Cycle Club.

Once the other members found out about his skills, he was

in demand for making replacement nuts, bolts, studs etc,

with all sorts of weird and wonderful thread pitch/dia

combinations which had been used in motorcycle manufacture

in the first half of the last century.

Edited by rab
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6 hours ago, Martin Shaw said:

The problem as I'm sure your aware is that restoring old steam locos requires fixings into existing castings which are ofted tapped whitworth hence stud especially are needed. It's possible to have whitworth screws and nuts made to order so they do cost

 

Why not make your own nuts & screws?

BSW taps & dies are still readily available off the shelf:

http://www.tapdie.com/html/bsw-_taps.html

http://www.tapdie.com/html/bsw-_dies.html

 

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1 hour ago, Jeff Smith said:

Once again on tonight's show the 9F is 'unique in the world'.

I think the North Norfolk and Mid Hants might have something to say about that!

Edited by Chris116
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Well, it is 'unique in the world' but only because of its single chimney. A very important detail that they keep missing off the narration. 

 

Also giggled at the 'GRAND Central Railway' sending the Hall :laugh:

 

That said, it's still a very entertaining series and I hope the NYMR get's plenty more passengers from it.

Edited by LNERandBR
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31 minutes ago, LNERandBR said:

Well, it is 'unique in the world' but only because of its single chimney. A very important detail that they keep missing off the narration. 

 

Also giggled at the 'GRAND Central Railway' sending the Hall :laugh:

 

That said, it's still a very entertaining series and I hope the NYMR get's plenty more passengers from it.

 

Both those things were mentioned in last week's programme, so they're probably not the last errors we'll hear.

 

They must have had problems with the fitting of the 9F's smoke reflectors - I don't think they could make their mind up whether to have them off or on, or off again or back on...:rolleyes:

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Interesting episode last night with some informative bits interspersed with the overplayed ‘dramas’. 
 

It would be even better if they were able to stitch the clips together in a slightly more logical/chronological order around the voiceover/narration. 
 

For me it could do with someone who knows one end of a locomotive from the other (or even has a grasp of geography) in the edit suite!

 

The Railway characters and their relationships are growing on me as the series develops. 

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