jasonb
Elder Statesman
Posts: 1,209
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Post by jasonb on Mar 6, 2020 21:21:54 GMT
But were Westbury's engines only excellent at the time? His boat engines may have been good performers in their day but things have moved on, you only need to look at Strickly business's posts on MEM to see that his designs are so out of date today. And most youngsters would rather use a big brushless motor and S8 lipo's these days.
Yes it is a shame some of the old Stuart designs and many others have been lost, well at least the availability of castings has, but with modern machines it is not too difficult to replicate the old designs by cutting from solid etc and add a few modern touches along the way.
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Post by Jo on Mar 6, 2020 21:47:57 GMT
But were Westbury's engines only excellent at the time? His boat engines may have been good performers in their day but things have moved on, you only need to look at Strickly business's posts on MEM to see that his designs are so out of date today. And most youngsters would rather use a big brushless motor and S8 lipo's these days. Most people starting out as model engineers don't attempt for their first model to design from scratch a high performance model engine intended for international racing/record breaking. What they do is find a reliable design and try building it, learning along the way I don't count sticking an electric motor in an off the shelf kit as model engineering. But if it interests the kids and in the end they realise they could achieve so much more by learning how to make swarf it is to the good. Jo P.S. Hemmingway can provide the drawings for the model engines they sell with modern measurements.
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Post by andyhigham on Mar 6, 2020 21:51:47 GMT
An aquaintence of mine has built model steam boats, the fastest over 129mph (a record). He leaves past methods in the past, his flash steam boilers produce so much superheat the steam pipe into the valve chest glows red hot. He is now using the same principles to build a full size version
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Post by steamer5 on Mar 7, 2020 3:58:13 GMT
The thing I still hate about the "old ways" and I have stated it on here many times, FRACTIONAL DIMENSIONS. Having to convert fractions to decimal before even picking up a micrometer is asking for a mistake to be made. The only time a fractional dimension is any use is when using with a tape measure It's not just that issue, it's the mental gymnastics you have to go through to decide whether one fraction is larger or smaller than another fraction. For example, is 27/64" bigger or smaller than 7/16"? Hi Roger, Totally agree! Youngest son moved to Canada 6 years ago. We make an annual trip & so I get contracted to help out on “projects” being Kiwi you have to have a deck....ok Canadians have them too.....so we are laying the foundations out & he’s decided that he needs to use imperial measurements.....ok on whole numbers but when he was having to divide fractions it was a different ball game! Told him just use metrics it’s so much easier, given that he knows nothing else since NZ went metric in 1967 & he’s a bit over 30! His excuse .... I’ve been doing some design work in imperial & it helps to practice! Oh he does piping & industrial design for a job. Cheers Kerrin
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Post by cplmickey on Mar 8, 2020 9:10:04 GMT
Don't any of you have a chart on the wall. Getting a fraction as an imperial measurement takes 2 seconds and there's no mistake to be made.
As for metric being easier, it depends. Our local carpet shop will only accept dimensions for a quote in inches because people constantly mix up the metric - is it 1.15, or 1.015, or even 1.5. At least with inches the whole numbers are easier to decide - 45, 39 and 59 respectively.
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Post by andyhigham on Mar 8, 2020 9:34:56 GMT
Don't any of you have a chart on the wall. Getting a fraction as an imperial measurement takes 2 seconds and there's no mistake to be made. As for metric being easier, it depends. Our local carpet shop will only accept dimensions for a quote in inches because people constantly mix up the metric - is it 1.15, or 1.015, or even 1.5. At least with inches the whole numbers are easier to decide - 45, 39 and 59 respectively. Reading off a chart carries the risk of a mistake, its easy to read off the wrong line When measuring less than about 2M I always use mm. eg. 1150mm, 1015mm or 1500mm. I was taught in school and college that mm and M are "standard", these days schools seem to teach to use cm Another place fraught with danger is adding and subtracting fractional dimensions with different bases
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Post by andyhigham on Mar 8, 2020 9:50:59 GMT
Another unit that belongs in the past is the acre. Who decided that an area 208.7103255711' x 208.710355711' was a good idea of a standard unit of area?
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oldnorton
Statesman
5" gauge LMS enthusiast
Posts: 696
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Post by oldnorton on Mar 8, 2020 10:20:04 GMT
Another unit that belongs in the past is the acre. Who decided that an area 208.7103255711' x 208.710355711' was a good idea of a standard unit of area? I like chains and furlongs ☹️
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Post by Roger on Mar 8, 2020 10:27:20 GMT
Another problem with Imperial Measurements as used in ME, is that the plans we have round sizes to the nearest, now obsolete, size. It may well be that the rounded size would actually have been nearer a Metric stock size. So we have the bizarre situation where the original size might scale to 3mm but it's been rounded to 1/8" stock which is getting progressively more difficult to source.
Few plans accurately scale metal thicknesses, they are usually too thin to be strong enough. Most models have much more chunky controls, platework and rods than would be true to scale, so it make no sense to slavishly follow the sizes on the plans. Of course, you need to be aware of these things and have the confidence to make the changes.
It simply makes no sense in the long term to gradually make life forever harder when switching to Metric solves all of the problems.
The world outside ME is largely oblivious to ME and BA thread sizes, because there are viable alternatives to every pitch and diameter within the Metric Coarse and Metric Fine standards. Taps and dies are readily available, and you only need a small number of threading inserts to be able to cover every size you will ever need to screw cut these.
I haven't made anything in Imperial Measurements in 20 years or more. Everything gets converted to Metric and made in Metric. Occasionally I've had to use UNC threads for a customer with US machines or BSP threads, but that's about all. The bottom line is that you don't need to use them, even it you're building SPEEDY or anything else.
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Post by jon38r80 on Mar 8, 2020 10:51:29 GMT
I don’t understand why there is so much controversy over standards of measurements that get used. Having been born long enough ago that I was educated with both metric and imperial units, I am comfortable with both , there are advantages to both systems. I’m just glad that we don’t use the wavelength of light , angstroms or some other esoteric unit of measurement. What does get right up my nose is when for reasons I cannot comprehend , a mixture of imperial and metric fasteners and measurements are used in the same component or machine. A family firm that made hydraulic cylinders had for a while to compromise their manufacturing process that made everything internally metric but had to use BSP fittings because they were destined for the European market (Which was supposed to already be metricated!)
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Post by Roger on Mar 8, 2020 11:38:20 GMT
I don’t understand why there is so much controversy over standards of measurements that get used. Having been born long enough ago that I was educated with both metric and imperial units, I am comfortable with both , there are advantages to both systems. I’m just glad that we don’t use the wavelength of light , angstroms or some other esoteric unit of measurement. What does get right up my nose is when for reasons I cannot comprehend , a mixture of imperial and metric fasteners and measurements are used in the same component or machine. A family firm that made hydraulic cylinders had for a while to compromise their manufacturing process that made everything internally metric but had to use BSP fittings because they were destined for the European market (Which was supposed to already be metricated!) It's controversial because it's an obstacle to the long term survival of the hobby which is going to be carried forward by generations who won't have even heard of Imperial Units. Measurement Standards bring clarity and uniformity, which is why we began adopting the Metric system in the 1970s. For those of us who were born into an Imperial world, these things are not really a problem. I could work in Imperial Measurements, but it's much easier to use Metric. If we want our hobby to thrive long into the future, we need to cast these obsolete measurements and standards aside and use the relevant standards of today. Swimming against the tide is futile in the long term, so we might as well gracefully accept that times they are a changing. Look at Model Engineering in Germany. They're not having the slightest difficulty in making their locomotives using the Metric system, and neither am I.
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Post by jon38r80 on Mar 8, 2020 12:01:40 GMT
When I was learning at school, the main argument for metrification came from Germany as they wanted their measurement systems adopted for the scientific world. Part of the demise of Empire after the 2nd world war. I agree with you that clinging to things just because that was the way our fathers did things is nonsensical. The constant China bashing that goes on is tied too it too. I have not bought tools made in this country for a long time because all the names don’t mean much anymore. They all just package stuff made in China, India, and South America and other places in the world where labour is cheap. Even German tools are often made in factories in the Far East. Carbide cutting inserts labelled with names like Mitsubishi, Kenametal .......... You can go on about it for hours. I do when someone or something sets me off. Clinging on to past practices is why we have no manufacturing worth talking about any more, why our trains are rubbish etc etc
Rant Over. Mr Meldrew is taking his ball home and doesn’t want to play anymore.
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Post by Roger on Mar 8, 2020 12:47:02 GMT
When I was learning at school, the main argument for metrification came from Germany as they wanted their measurement systems adopted for the scientific world. Part of the demise of Empire after the 2nd world war. I agree with you that clinging to things just because that was the way our fathers did things is nonsensical. The constant China bashing that goes on is tied too it too. I have not bought tools made in this country for a long time because all the names don’t mean much anymore. They all just package stuff made in China, India, and South America and other places in the world where labour is cheap. Even German tools are often made in factories in the Far East. Carbide cutting inserts labelled with names like Mitsubishi, Kenametal .......... You can go on about it for hours. I do when someone or something sets me off. Clinging on to past practices is why we have no manufacturing worth talking about any more, why our trains are rubbish etc etc Rant Over. Mr Meldrew is taking his ball home and doesn’t want to play anymore. Let's not forget that one reason that Britain was the workshop of the World was because of the ready availability of cheap labour. The Trade Union Movement rescued us from the appalling conditions and indifference to Worker's health. When you can't abuse your workforce any more, industry simply moves elsewhere. It's happened to Britain, Hong Kong, then Japan, and one day it will be China too. One day we'll run out of people to take advantage of, and we'll all have to pay a realistic price for things, unlike today. It's a mistake to think that China is only making rubbish products though, even though some of them clearly are. Their Carbide tooling is on a par with anything made anywhere in the World. They're making Jet Engines and Airliners, and some of the most impressive structures anywhere. I agree that you can't trust many names any more, so you have to just try the products and evaluate them for yourself. There are very few 'premium' products these days, only premium prices for average goods. One name I do trust is Mitutoyo though. I'm yet to have a bad experience with anything I've bought with that badge.
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Post by RGR 60130 on Mar 8, 2020 13:05:00 GMT
Metric might be the long term future of model engineering but until someone sits down and re-draws imperial designs into metric, it's going to take a long time to happen. It's not commercially viable for the current ME suppliers to employ someone to do it so that leaves model engineers themselves to do it. I'm not going to hold my breath.
Reg
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jasonb
Elder Statesman
Posts: 1,209
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Post by jasonb on Mar 8, 2020 13:30:32 GMT
All very well saying use the current standard and do it all in metric but not all international standards are metric. Model engineering does not just cover trains, the standard worldwide thread for glow plugs and miniature sparkplugs for example is 1/4 UNEF or over on ME we have a lot more home workshop users who are interested in cameras and astronomy what should they do with their 1/4" UNC camera mounts (use dto be whitworth which still fits) etc that they want to make. And would a 125mm loco fit on 5" (127mm) track
I've also heard that Model Engineering is quite popular in the US, good luck getting them to make their models in metric. I'm still happy to buy their casting kits and then build as I see fit. Might have metric threads but if hex fixings I find imperial size hex works well at 1/16" per mm dia of thread. I will substitute BSP for NPT or should I say G threads. Will keep the DP gears that are often supplied as changing to MOD may not match the cast boss ctrs or give the wrong number of teeth though I have cut 0.8MOD with 32DP cutters to Mod sizes and so on.
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Post by Jo on Mar 8, 2020 18:04:56 GMT
Metric might be the long term future of model engineering but until someone sits down and re-draws imperial designs into metric, it's going to take a long time to happen. It's not commercially viable for the current ME suppliers to employ someone to do it so that leaves model engineers themselves to do it. I'm not going to hold my breath. Reg
Every model I make I convert into metric. Certain casting suppliers are only too happy for me to provide them with A4 PDF versions of their drawings cleaned up, parted out and marked up with metric measurements so that they can provide them to their modern customers.
All very well saying use the current standard ….. And would a 125mm loco fit on 5" (127mm) track ...I've also heard that Model Engineering is quite popular in the US, good luck getting them to make their models in metric. I think you will find that the standard for mid sized model locomotives is a nice round 4 7/8" the other side of the pond and they have 7 1/2" not 7 1/4". Please don't get me on plans for models being presented in 1st rather than 3rd angle or even worse a mixture of both
There are a lot of weird sizes used in making models, that does not necessarily make them right or help to encourage youngsters to start out in this hobby. If you don't try to present things in language they understand it is a lot harder to get them to listen or for them to find actually they could enjoy being a model engineer.
Jo
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jasonb
Elder Statesman
Posts: 1,209
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Post by jasonb on Mar 8, 2020 18:48:13 GMT
I suppose to do it properly in metric one should start off with a preferred metric scale and build to suit so all the tracks would need replacing with 143.5mm and 71.75mm gauge using 1:10 and 1:20 as the metric scales. Actually probably not a bad time to do it as when coal is banned you will all be having to model modern diesels where the full size was built in metric so 1:10 would be so simple to scale Must admit I'm not a fan of the type of conversion Jo mentions which is just a direct calculated conversion to decimal metric so you still get sizes like 9.53mm or 22.22mm. If you are going to do a metric version then go the whole hog and use metric threads where possible, stock metric material sizes, whole millimeter dimensions as much as possible, etc. Not much use providing a drawing with 9.53mm on it when 3/8" stock is no longer available or the poor clueless beginner has not heard of it and thinks they have to machine a length of 10mm stock down to 9.53mm.
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Post by Roger on Mar 8, 2020 19:00:03 GMT
Personally, I don't see the need to round all sizes scaled from Works Drawings. If you're machining something to a size, it's not important to be even to the nearest 0.1mm If you're scaling something, why not just scale it? I just convert Works Drawings to three decimal places and use that for 3D modelling. It's only when you're going to use the actual stock diameter or thickness that you need to worry about rounding things. Even then, Sheet material is always thinner than the nominal size, so you're better off buying it, then measuring what you actually have and then make the 3D model to what you have. In reality, there aren't that many situations where you actually use the stock material size for the finished dimension. In any case, the surface finish and tolerance of stock material is not really ideal for use unless the size is unimportant.
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Post by goldstar31 on Mar 8, 2020 19:09:09 GMT
Most of the old fasteners and whatever came from Whiston's 'Seen my ca(tologue) in Model Engineer. They were ex- government or surplus stocks--- rather like things offered on E-Bay today.
Thoughts before I go for some 70% proof whisky. Don't ask me why or where they get the gunpowder but where did the Romans get 4foot 8 and half inches from. That's the width of the chariot ruts in the Roman Wall and copied by Stephenson and co?
I like the Megalithic Yard but you have to read Professor Thom or possibly Knight and Lomas armed with sticks and pieces of rope and wait for the Summer Solstice and the Planet Venus. I'm quite serious! Somewhat whimsically
Norman
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millman
Part of the e-furniture
Posts: 298
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Post by millman on Mar 8, 2020 19:46:53 GMT
I thought it was five foot but with the flanges on the outside, when flanges were moved inside it became four foot eight and a half. Think I might go and have a nice single malt now.
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