Hi Will Allan Terry
I appreciate your replies. I don't think my perspective is being quite understood. I am talking about the last extra thing we can do on top of all the things that you say. This Forum is rich in discussion of all the things necessary for good running. You are talking about what I regard as prerequisites to good running. Yes, much more important than what I am contributing here.
But I just want to add in this thread that last extra thing beyond what you are saying. It may have as much significance as that errant layer of varnish on wheel treads that Terry mentions - maybe considerably less. Piffling in other words.
Look. I have spent nearly 40 years playing in orchestras. People in orchestras spend their lives from early childhood perfecting their art and craft. When we play in a concert we spend about 15 hours rehearsing what is already pretty near perfect. Then, after the concert, the following days we may record the music. We will spend another 12 to 24 hours yet further perfecting what was already perfect, that we have been studying how to play since almost the day we were born. A man in a box with practically a stethescope in terms of the detail of sound he can artificially hear will be telling all of us what doesn't sound minutely right out of all the thousands of notes that are being played.
I am talking about a similar discipline of perfection. What I am talking about in this thread is an infinitessimally small thing that just might make an extra bit of difference for good running beyond and on top of what you are saying, to further perfect what we do - but it is quite an easy thing to do, much easier that all the things you talk about, we can make our track the proper gauge - dead simple - it would not add one second of extra time to the making of any track.
And today I saw that the 2mm Gauge people have standardized the equivalent of the Protofour Mark 2 tool with its 0.2mm gauge widening washer in their standards.
Here is the relevant part of the Scalefour Digest:
http://2mm.org.uk/standards/basicstd.htm
And here is the 2mm Association equivalent. They have a standard that reflects much more what happens on the prototype. Double all the figures and you can see It standardizes what our Protofour Mark 2 tool actually does (+0.2mm), but puts a radius below which it should be used (48"). And it modifies the figures for the different prototype gauges, unlike ours.
48" = 1219mm. The 2mm Assoc standardizes at approximately the intersection of the curved yellow and straight blue lines on the graph as being the place from which you need 0.2mm gauge widening, just what I would have surmised from the figures and graph, as I know that this yellow line is a little too high. By the way the wheel standards show like P4 a narrow BB, 8.5mm down from true scale 8.9mm, meaning that they have the BB reduced from the prototype four times as much as we do - so they have much less reason than us to have prototypical gauge widening.
So this would mean in P4 that any curve below 48" would be 0.2mm wide to 18.83mm. Simply standardizing what was the instruction with the demise of the Mark 1 Track Gauge tool, except that the tool was meant to be used for all curves.
So that is already in any case a legitimate starting point for Jon with his Connah's Quay layout.
I am not expecting anyone "senior" as it were in the Society to corroborate here what I am saying. I am thinking aloud for anyone who might be similarly curious and open minded.
Here is part of the issue of Prototype 11 (August 1976) where MSC - I assume Malcolm Cross - introduces the Mark 2 Track Gauge. (from http://www.scalefour.org/members/protofoursociety/ )
Society Gauge Widening Tool
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Julian Roberts
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Re: Society Gauge Widening Tool
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Allan Goodwillie
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Re: Society Gauge Widening Tool
That's interesting Julian, 
I do know what you are on about and there are more than suspicions about track going tight to gauge after laying - as you know I have been trying to suggest ways of making track which will keep the important dimensions correct and which will maybe also give a little bit more allowance for tightening after construction. I do not use the triangular gauge at all, so have no experience myself in using it and how the track behaves after setting with the gauge.
The track gauges now sold by C&L suggest to me that the previous gauge was perhaps not quite what is required and that the new gauges are a better option if building using their components. Previous gauges of all types hold the rail vertically so what happens to the rail when placed in C&L chairs when the gauge is taken away?
The design is supposed to hold the rail at an angle, so the new type of gauges should work with that. I am not so sure that on curves the triangular gauge will - I can see a few experiments coming on some evening.The original C&L gauge, by the way, was designed to only lightly hold the top of the rail, allowing the rail to sit in the chair, hopefully at the right angle. It was a bit of a pain to use as it would often pop off at inappropriate moments, and some people thought it would hold the rail firmly like the previous deeper track gauges supplied by Studiolith onwards.
Although a great deal has been written about track construction elsewhere I am still going to put something up on the forum in due course under the starters banner. As you know we have discussed the problems I have had to deal with over the years track-wise on other projects, both large and small and that I do have some techniques not necessarily used elsewhere to keep it right. Not all you see in print works out in practice. We are going to be laying track soon on the extension and see if everyone has managed to get their track construction right. The proof of the pudding is in the eating.
Considering these are first points by quite a few of our members, they all look pretty good efforts and if laid correctly I hope we will experience little trouble. What we need now is a well prepared surface, the boards are done and ready and some of the electrics pre-prepared, key points completed - looking forward to this! The new layout I am building has many fairly tight points, being industrial and most of the points have been built ready for laying. I still have a few to do but I am going to use them as samples and demonstration pieces for the Starters Group when we come to that, at the later part of the year - so do not expect more on the subject here until I get down to that.
Allan
I do know what you are on about and there are more than suspicions about track going tight to gauge after laying - as you know I have been trying to suggest ways of making track which will keep the important dimensions correct and which will maybe also give a little bit more allowance for tightening after construction. I do not use the triangular gauge at all, so have no experience myself in using it and how the track behaves after setting with the gauge.
The track gauges now sold by C&L suggest to me that the previous gauge was perhaps not quite what is required and that the new gauges are a better option if building using their components. Previous gauges of all types hold the rail vertically so what happens to the rail when placed in C&L chairs when the gauge is taken away?
The design is supposed to hold the rail at an angle, so the new type of gauges should work with that. I am not so sure that on curves the triangular gauge will - I can see a few experiments coming on some evening.The original C&L gauge, by the way, was designed to only lightly hold the top of the rail, allowing the rail to sit in the chair, hopefully at the right angle. It was a bit of a pain to use as it would often pop off at inappropriate moments, and some people thought it would hold the rail firmly like the previous deeper track gauges supplied by Studiolith onwards.
Although a great deal has been written about track construction elsewhere I am still going to put something up on the forum in due course under the starters banner. As you know we have discussed the problems I have had to deal with over the years track-wise on other projects, both large and small and that I do have some techniques not necessarily used elsewhere to keep it right. Not all you see in print works out in practice. We are going to be laying track soon on the extension and see if everyone has managed to get their track construction right. The proof of the pudding is in the eating.
Considering these are first points by quite a few of our members, they all look pretty good efforts and if laid correctly I hope we will experience little trouble. What we need now is a well prepared surface, the boards are done and ready and some of the electrics pre-prepared, key points completed - looking forward to this! The new layout I am building has many fairly tight points, being industrial and most of the points have been built ready for laying. I still have a few to do but I am going to use them as samples and demonstration pieces for the Starters Group when we come to that, at the later part of the year - so do not expect more on the subject here until I get down to that.
Allan
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Armchair Modeller
Re: Society Gauge Widening Tool
You can't compare 2FS and P4 standards like that. The relationship between 2mm finescale wheels and rails is totally different. Although called "finescale", 2mm finescale is coarser that P4 (relatively speaking) - closer in fact to EM than P4. The mass of 2mm stock is around 25% that of 4mm stock too. You are comparing apples with oranges.
In any case, it doesn't stop 2FS stock derailing - trust me, I have experience.
In any case, it doesn't stop 2FS stock derailing - trust me, I have experience.
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Julian Roberts
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Re: Society Gauge Widening Tool
Cheers Allan.
Well Armchair everything I put here is a kind of question for which I am seeking answers or counterpoints. Allan and I see each other regularly so we can actually converse...soo last century!
Yeah I mentioned that the wheels in 2mm are 4 times further apart than ours relatively. I looked no further at everything else, but clearly that will change other vital dimensions. Except, I noticed the gauge is exactly half ours, not half EM.
But do you think Armchair that there is therefore nothing to be gained looking at the 2mm gauge widening standard on its own.....?
After all, I've said lots of times that I am only questioning this aspect of the P4 standards.
And surely what happened with the Mk 2 gauge replacing the Mk 1 demonstrates this - a change of standard could be done without it affecting anything else?
Malcolm Cross comes along, "Hey Guys we're changing the gauge widening - but don't panic, keep calm and carry on, everything is fine and you can continue just as you were! "
Seems to me the standards reflect the Mark 1 triangular tool and were never changed to reflect the "new" Mark 2 Track Gauge, and now the Society issue obviously is the equivalent of the Mark 1 so they reflect what's actually there..... but
Can you explain the 0.22mm at 528mm Armchair ?
Well Armchair everything I put here is a kind of question for which I am seeking answers or counterpoints. Allan and I see each other regularly so we can actually converse...soo last century!
Yeah I mentioned that the wheels in 2mm are 4 times further apart than ours relatively. I looked no further at everything else, but clearly that will change other vital dimensions. Except, I noticed the gauge is exactly half ours, not half EM.
But do you think Armchair that there is therefore nothing to be gained looking at the 2mm gauge widening standard on its own.....?
After all, I've said lots of times that I am only questioning this aspect of the P4 standards.
And surely what happened with the Mk 2 gauge replacing the Mk 1 demonstrates this - a change of standard could be done without it affecting anything else?
Malcolm Cross comes along, "Hey Guys we're changing the gauge widening - but don't panic, keep calm and carry on, everything is fine and you can continue just as you were! "
Seems to me the standards reflect the Mark 1 triangular tool and were never changed to reflect the "new" Mark 2 Track Gauge, and now the Society issue obviously is the equivalent of the Mark 1 so they reflect what's actually there..... but
Can you explain the 0.22mm at 528mm Armchair ?
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Armchair Modeller
Re: Society Gauge Widening Tool
Julian,
The gauge may be half of P4, but the wheel standards most definitely are not. The wheel profile is nothing like as fine, relative to scale. Wheels are set further in than scale too. That is why I compared it to EM. The gauge/wheel relationship in 2FS gives a lot of slop. It has been argued that no gauge widening is necessary for 2FS unless you use very sharp curves.
I doubt that anyone modelling in 2mm scale uses the 0.22mm gauge widening. It is purely theoretical. I don't see how it can be called a standard in the way that you infer. The 2FS standards have a lot of slop, so gauge widening ought only to be necessary on very tight curves. In any case, most 2mm modellers use Easitrac these days, which has a fixed gauge. Also, many use converted N gauge locos, which were originally designed to go round very sharp curves.
The gauge may be half of P4, but the wheel standards most definitely are not. The wheel profile is nothing like as fine, relative to scale. Wheels are set further in than scale too. That is why I compared it to EM. The gauge/wheel relationship in 2FS gives a lot of slop. It has been argued that no gauge widening is necessary for 2FS unless you use very sharp curves.
I doubt that anyone modelling in 2mm scale uses the 0.22mm gauge widening. It is purely theoretical. I don't see how it can be called a standard in the way that you infer. The 2FS standards have a lot of slop, so gauge widening ought only to be necessary on very tight curves. In any case, most 2mm modellers use Easitrac these days, which has a fixed gauge. Also, many use converted N gauge locos, which were originally designed to go round very sharp curves.
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Terry Bendall
- Forum Team
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- Joined: Sun Jul 27, 2008 7:46 am
Re: Society Gauge Widening Tool
Allan Goodwillie wrote:Previous gauges of all types hold the rail vertically so what happens to the rail when placed in C&L chairs when the gauge is taken away?
An interesting question, and as Allan says, one that would warrant investigating. One of the problems is that how to you measure if the rail is still vertical, or what angle, if any it takes up?
The flat bottom rail system developed by Colin Craig of this parish has a system of base plates to which the rail is soldered and which will then give the required inclination of the rail. This of course means that the rail will stay at the correct angle once the gauge is removed. The BR1 and BR2 fixings that Colin supplies give the inclination and for rail where Pandrol clips are used, a small baseplate is soldered under the rail and the clips are cosmetic and applied afterwards.
Perhaps we need to go back to soldered track and cosmetic chairs?
Flat bottom track became increasing common on the prototype after the end of WW2 yet many layouts set in the popular 1950 to 1965 use bullhead track.Terry Bendall
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Julian Roberts
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Re: Society Gauge Widening Tool
Armchair!
Yes, the 2mm (http://2mm.org.uk/standards/basicstd.htm ) wheels BB are roughly 0.4mm narrower than scale; ours are 0.2mm narrower (to be precise, between 0.12 and 0.22 narrower taking into account the tolerance). So doubled to our scale their BB would be 0.8, four times as much as ours.
Their flange width is 0.3mm, so doubled that's 0.6, while ours is 0.4. So their flanges in our scale would be twice as much as ours.
So translate that into Running Clearance (though that doesn't seem to be a term used apart from in that book by Iain Rice) - I think we normally abbreviate it to Clearance, or slop.
We have 17.67mm, and 2 flanges of 0.4mm. 17.67 + 0.8 = 18.47. Take that away from 18.83 and you get 0.36mm Running Clearance
We also have 17.75, so that plus 2 flanges comes to 18.55. Take that away from 18.83 gives us 0.28.
So we have between 0.28 and 0.36 Running Clearance (on straight track
)
The 2mm people have a BB of 8.51mm...interestingly they don't publish a tolerance, though they do for Irish gauge, a tolerance of 0.07mm, so that's an example of things being thought out, or not... And flanges of 0.30
So their BB of 8.51, plus 0.6, gives 9.11mm. Their track is 9.42mm, so they have Running Clearance of 0.31mm, which doubled into our scale is 0.62, roughly twice as much as us.
The prototype has 17.87 - 17.89 BB, and flanges of 0.38; that comes to 18.63 to 18.65mm, so the Running Clearance is between 0.18 and 0.2 mm
So yes, they have more slop and therefore that much less need for gauge widening.
I am losing you slightly
as their standards say the gauge widening is 0.1mm (below 24"). Presumably you are translating it into our terms (0.2mm) and then putting in our actual published figure (0.22mm).
Ah! - I have just thought, maybe you are misunderstanding my question.
My point is that, despite their reduced need for gauge widening, they have a published standard that gives more widening than us. Their standard gives what ours might have given if it had been altered when the Mark 2 tool was introduced.
My question to you
refers to our standards, at our gauge, in our scale. It is the question I have been asking throughout this whole thread!
Julian,
The gauge may be half of P4, but the wheel standards most definitely are not. The wheel profile is nothing like as fine, relative to scale. Wheels are set further in than scale too. That is why I compared it to EM. The gauge/wheel relationship in 2FS gives a lot of slop. It has been argued that no gauge widening is necessary for 2FS unless you use very sharp curves.
I doubt that anyone modelling in 2mm scale uses the 0.22mm gauge widening. It is purely theoretical. I don't see how it can be called a standard in the way that you infer. The 2FS standards have a lot of slop, so gauge widening ought only to be necessary on very tight curves. In any case, most 2mm modellers use Easitrac these days, which has a fixed gauge. Also, many use converted N gauge locos, which were originally designed to go round very sharp curves.
Yes, the 2mm (http://2mm.org.uk/standards/basicstd.htm ) wheels BB are roughly 0.4mm narrower than scale; ours are 0.2mm narrower (to be precise, between 0.12 and 0.22 narrower taking into account the tolerance). So doubled to our scale their BB would be 0.8, four times as much as ours.
Their flange width is 0.3mm, so doubled that's 0.6, while ours is 0.4. So their flanges in our scale would be twice as much as ours.
So translate that into Running Clearance (though that doesn't seem to be a term used apart from in that book by Iain Rice) - I think we normally abbreviate it to Clearance, or slop.
We have 17.67mm, and 2 flanges of 0.4mm. 17.67 + 0.8 = 18.47. Take that away from 18.83 and you get 0.36mm Running Clearance
We also have 17.75, so that plus 2 flanges comes to 18.55. Take that away from 18.83 gives us 0.28.
So we have between 0.28 and 0.36 Running Clearance (on straight track
)The 2mm people have a BB of 8.51mm...interestingly they don't publish a tolerance, though they do for Irish gauge, a tolerance of 0.07mm, so that's an example of things being thought out, or not... And flanges of 0.30
So their BB of 8.51, plus 0.6, gives 9.11mm. Their track is 9.42mm, so they have Running Clearance of 0.31mm, which doubled into our scale is 0.62, roughly twice as much as us.
The prototype has 17.87 - 17.89 BB, and flanges of 0.38; that comes to 18.63 to 18.65mm, so the Running Clearance is between 0.18 and 0.2 mm
So yes, they have more slop and therefore that much less need for gauge widening.
I am losing you slightly
I doubt that anyone modelling in 2mm scale uses the 0.22mm gauge widening.
as their standards say the gauge widening is 0.1mm (below 24"). Presumably you are translating it into our terms (0.2mm) and then putting in our actual published figure (0.22mm).
Ah! - I have just thought, maybe you are misunderstanding my question.
My point is that, despite their reduced need for gauge widening, they have a published standard that gives more widening than us. Their standard gives what ours might have given if it had been altered when the Mark 2 tool was introduced.
My question to you
Can you explain the 0.22mm at 528mm Armchair ?
refers to our standards, at our gauge, in our scale. It is the question I have been asking throughout this whole thread!
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Allan Goodwillie
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Re: Society Gauge Widening Tool
Getting back to Terry,
I have done some work on that Terry when I was building Grayrigg twenty years ago, using C&L point kits etc. for the first time. They were the early ones originally sold via Alan Gibson and which I used to sell at the Museum. I was always being asked what they were like to build and I had to admit that at that time I had not tried them. Once I had time to build Grayrigg a few years later it gave me chance to try out various combinations of things to see what worked best. I built two of each system of points on the open sections of the layout, but stuck to what I knew when building points for the hidden storage as I wanted to have something reliable as all the storage was under the main running boards on a lower level. I made 8 tandem points over the Christmas holidays one year using ply and rivets for the entries into the up and down storage yards. These points after minimal tweaking have all worked well thank goodness, although I have had some problems with the point motors (Seep) due to the steel actuating arm working loose and not closing the points correctly from time to time.
The mainline points, well I could fill a book with both good and bad, but have over time resolved all the different problems and now have a method which does work well and which gets the best from both worlds. So rather than write a book I intend publishing on the forum what I now do and the method I have introduced to the West group and which I am going to get the starters group on to as well.
It uses a combination of both systems. Wooden sleepers, rivets holding the track in essential areas with chairs cosmetically stuck on and other areas where the chairs are used on their own, but gauge widened to overcome "bend back" within the chairs. This is why I was a bit dismayed to hear that riveting tools are only spasmodically available. We are having to pass them around nowadays just to build our new railways.
Grayrigg runs pretty well when I am able to maintain it properly and I will probably do a write-up sometime. It was always built as a proving ground, never intended for display. At the moment it is out of commission due to the garage being still full of my Mother's possessions and items brought from the house with the intention of "finding another home" a few days of good weather would maybe solve all of that.
Running out of time as Richard is coming down this morning and we are going to get into my friend next door -John's garage. This is where Burntisland is stored so we will get loaded and up to Dechmont for another weekend of running. I will be there on Saturday, but the West Group are going on a photographic trip to Lanarkshire and surrounding areas to find the best location for Calderside's new backscene.
I have no experience of building the new points introduced in recent years although one or two of the East Group have bought examples and seem pleased with the results. Given the cost of each individual point, for me building larger layouts it is too much, but I think they look superb once made up and seem to run OK. They do have all the different types of chair as part of the system and therefor the points look right, but there are so many variations between companies as to design shape and use of chair I wonder if it is worth pursuing unless it happens to fit your company and time period. I have built a mainline crossover on curved super elevated track on Grayrigg which in real life would require quite a number of variations of chair to get them all right. Richard Chown showed us a list of chairs available in NBR days for the building of track and the sheer number! I must get a copy from Richard and put it up here somewhere. That's the door now!
I have done some work on that Terry when I was building Grayrigg twenty years ago, using C&L point kits etc. for the first time. They were the early ones originally sold via Alan Gibson and which I used to sell at the Museum. I was always being asked what they were like to build and I had to admit that at that time I had not tried them. Once I had time to build Grayrigg a few years later it gave me chance to try out various combinations of things to see what worked best. I built two of each system of points on the open sections of the layout, but stuck to what I knew when building points for the hidden storage as I wanted to have something reliable as all the storage was under the main running boards on a lower level. I made 8 tandem points over the Christmas holidays one year using ply and rivets for the entries into the up and down storage yards. These points after minimal tweaking have all worked well thank goodness, although I have had some problems with the point motors (Seep) due to the steel actuating arm working loose and not closing the points correctly from time to time.
The mainline points, well I could fill a book with both good and bad, but have over time resolved all the different problems and now have a method which does work well and which gets the best from both worlds. So rather than write a book I intend publishing on the forum what I now do and the method I have introduced to the West group and which I am going to get the starters group on to as well.
It uses a combination of both systems. Wooden sleepers, rivets holding the track in essential areas with chairs cosmetically stuck on and other areas where the chairs are used on their own, but gauge widened to overcome "bend back" within the chairs. This is why I was a bit dismayed to hear that riveting tools are only spasmodically available. We are having to pass them around nowadays just to build our new railways.
Grayrigg runs pretty well when I am able to maintain it properly and I will probably do a write-up sometime. It was always built as a proving ground, never intended for display. At the moment it is out of commission due to the garage being still full of my Mother's possessions and items brought from the house with the intention of "finding another home" a few days of good weather would maybe solve all of that.
Running out of time as Richard is coming down this morning and we are going to get into my friend next door -John's garage. This is where Burntisland is stored so we will get loaded and up to Dechmont for another weekend of running. I will be there on Saturday, but the West Group are going on a photographic trip to Lanarkshire and surrounding areas to find the best location for Calderside's new backscene.
I have no experience of building the new points introduced in recent years although one or two of the East Group have bought examples and seem pleased with the results. Given the cost of each individual point, for me building larger layouts it is too much, but I think they look superb once made up and seem to run OK. They do have all the different types of chair as part of the system and therefor the points look right, but there are so many variations between companies as to design shape and use of chair I wonder if it is worth pursuing unless it happens to fit your company and time period. I have built a mainline crossover on curved super elevated track on Grayrigg which in real life would require quite a number of variations of chair to get them all right. Richard Chown showed us a list of chairs available in NBR days for the building of track and the sheer number! I must get a copy from Richard and put it up here somewhere. That's the door now!
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Armchair Modeller
Re: Society Gauge Widening Tool
Julian,
If it makes things any clearer...
The gauge widening figure quoted for 2mm scale is theoretical. There is no gauge widening tool for 2mm scale. Therefore there is no precise way of doing gauge widening in 2mm scale. There is lots of slop in 2mm standards so most people don't bother. If they use Easitrac trackbases, they can't use gauge widening anyway, because the gauge is fixed. Therefore, I doubt if any 2mm modeller has practical experience of using the precise figures for gauge widening quoted in the 2mm standards.
Quoting 2mm scale as a shining example of what P4 modellers should be doing is a little eccentric.
Sorry if that sounds rude, but that is exactly how I feel about it.
If it makes things any clearer...
The gauge widening figure quoted for 2mm scale is theoretical. There is no gauge widening tool for 2mm scale. Therefore there is no precise way of doing gauge widening in 2mm scale. There is lots of slop in 2mm standards so most people don't bother. If they use Easitrac trackbases, they can't use gauge widening anyway, because the gauge is fixed. Therefore, I doubt if any 2mm modeller has practical experience of using the precise figures for gauge widening quoted in the 2mm standards.
Quoting 2mm scale as a shining example of what P4 modellers should be doing is a little eccentric.
Sorry if that sounds rude, but that is exactly how I feel about it.
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Allan Goodwillie
- Posts: 916
- Joined: Sun Jul 20, 2008 7:00 pm
Re: Society Gauge Widening Tool
Terry I've been adding to my knowledge about super elevated crossovers. I was talking to Richard Chown today about this stream and that I had mentioned the crossover. He asked me how I had built it. I said that to get it to work I had made the second elevation higher than the first so that to all intents and purposes it was all on the same plane, but I did not know if that was right or if things were more complicated with such things.
The answer was that in real life that is what would have happened, but in that case there would not have been reason to have too many types of chair and that it might have been possible to build it using the normal chairs. (So I was wrong on that issue) His comment was that locomotives and trains going over the crossover would have a max speed of 15mph. In fact in most cases such a crossover would be avoided if possible. I have asked him if he could send me a copy of the list of different types of chair available to the NBR at the turn of the century.
I am sure it will surprise many and of course that was just one example.There are no chairs etc. available for one of the points on my new layout as it has inside securing blocks on the chairs and is of a different lighter rail section.
The answer was that in real life that is what would have happened, but in that case there would not have been reason to have too many types of chair and that it might have been possible to build it using the normal chairs. (So I was wrong on that issue) His comment was that locomotives and trains going over the crossover would have a max speed of 15mph. In fact in most cases such a crossover would be avoided if possible. I have asked him if he could send me a copy of the list of different types of chair available to the NBR at the turn of the century.
I am sure it will surprise many and of course that was just one example.There are no chairs etc. available for one of the points on my new layout as it has inside securing blocks on the chairs and is of a different lighter rail section.
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Julian Roberts
- Posts: 1397
- Joined: Sat Jan 09, 2010 11:33 pm
Re: Society Gauge Widening Tool
Terry, Allan
As you may remember Allan I was making a pitch for our Calderside extension to be in FB track, but of course the consensus was that on a branch byway FB track would have been unlikely even in 1960, and it would lock the time period to around then, while as it is we can take the time period back to 1915 or so if we wish.
Since the line to Neilston around Lyoncross was relayed in about 2000, I have been borrowing one of the discarded BR1 baseplates as a useful(?) item of furniture. Bill Bedford made up an etch from the photos that incorporated fold up spikes. I made up a 60' panel and sent it to the then editor of the MRJ, who had shown interest, never got it back, I can't think of his name just now nor find the photos I took of my effort.
Armchair, please don't think I am quoting 2mm scale as a shining example of what P4 modellers should be doing. I don't think I ever said that, and if I give that impression that is completely unintentional.
I earlier said
All I have been saying, and the quotes regarding that one aspect of the 2mm standards - gauge widening -is an example, is that there is something to be learned from everything. Just as there is lots we can learn from a fine 00 layout, for example "Alloa" made by other modellers in Glasgow - like Burntisland, it is a 3D historical document of a certain place at a certain time, but in this case a rather more recent time, one that many of us remember still. I did see one derailment while I spent about 20 minutes watching it at the Glasgow Model Rail show in February, though not on this junction:
I don't know what radius these curves are, nor whether they are modelled exactly to scale or compressed with modellers licence, but they look sharp to me and the kind of area of radius where things start getting interesting.
I happen to be being leant the 2mm book on Track. The front cover is a picture of Shrewsbury.
It does have stuff about gauge widening, there is a triangular tool:
I have no further knowledge about 2mm things, this is not to dispute what you say actually happens in practical terms, which is of course much more to the point.
It also has a picture from Shrewsbury of a ground level view, and gives the radius of these curves, which gives me a handle on reality - so there are some curves of this severity (4.5 chains) on the mainline! That's 1188mm, or 3' 11".
Let me reiterate, this has nothing to do with holding up a shining example for us P4 modellers to follow. I am interested in good modelling wherever it may be.
I may sound a bit like Jeremy Paxman in his famous interview with Michael Howard where he asked the same question 14 times. I don't think anyone has an answer though...?
Why is our Gauge Widening Standard 0.22mm at 528mm?
The flat bottom rail system developed by Colin Craig of this parish has a system of base plates to which the rail is soldered and which will then give the required inclination of the rail. This of course means that the rail will stay at the correct angle once the gauge is removed. The BR1 and BR2 fixings that Colin supplies give the inclination and for rail where Pandrol clips are used, a small baseplate is soldered under the rail and the clips are cosmetic and applied afterwards.
Perhaps we need to go back to soldered track and cosmetic chairs?
As you may remember Allan I was making a pitch for our Calderside extension to be in FB track, but of course the consensus was that on a branch byway FB track would have been unlikely even in 1960, and it would lock the time period to around then, while as it is we can take the time period back to 1915 or so if we wish.
Since the line to Neilston around Lyoncross was relayed in about 2000, I have been borrowing one of the discarded BR1 baseplates as a useful(?) item of furniture. Bill Bedford made up an etch from the photos that incorporated fold up spikes. I made up a 60' panel and sent it to the then editor of the MRJ, who had shown interest, never got it back, I can't think of his name just now nor find the photos I took of my effort.
Armchair Modeller wrote:Julian,
If it makes things any clearer...
The gauge widening figure quoted for 2mm scale is theoretical. There is no gauge widening tool for 2mm scale. Therefore there is no precise way of doing gauge widening in 2mm scale. There is lots of slop in 2mm standards so most people don't bother. If they use Easitrac trackbases, they can't use gauge widening anyway, because the gauge is fixed. Therefore, I doubt if any 2mm modeller has practical experience of using the precise figures for gauge widening quoted in the 2mm standards.
Quoting 2mm scale as a shining example of what P4 modellers should be doing is a little eccentric.
Sorry if that sounds rude, but that is exactly how I feel about it.
Armchair, please don't think I am quoting 2mm scale as a shining example of what P4 modellers should be doing. I don't think I ever said that, and if I give that impression that is completely unintentional.
I earlier said
I am thinking aloud for anyone who might be similarly curious and open minded.
All I have been saying, and the quotes regarding that one aspect of the 2mm standards - gauge widening -is an example, is that there is something to be learned from everything. Just as there is lots we can learn from a fine 00 layout, for example "Alloa" made by other modellers in Glasgow - like Burntisland, it is a 3D historical document of a certain place at a certain time, but in this case a rather more recent time, one that many of us remember still. I did see one derailment while I spent about 20 minutes watching it at the Glasgow Model Rail show in February, though not on this junction:
I don't know what radius these curves are, nor whether they are modelled exactly to scale or compressed with modellers licence, but they look sharp to me and the kind of area of radius where things start getting interesting.
I happen to be being leant the 2mm book on Track. The front cover is a picture of Shrewsbury.
It does have stuff about gauge widening, there is a triangular tool:
I have no further knowledge about 2mm things, this is not to dispute what you say actually happens in practical terms, which is of course much more to the point.
It also has a picture from Shrewsbury of a ground level view, and gives the radius of these curves, which gives me a handle on reality - so there are some curves of this severity (4.5 chains) on the mainline! That's 1188mm, or 3' 11".
Let me reiterate, this has nothing to do with holding up a shining example for us P4 modellers to follow. I am interested in good modelling wherever it may be.
I may sound a bit like Jeremy Paxman in his famous interview with Michael Howard where he asked the same question 14 times. I don't think anyone has an answer though...?
Why is our Gauge Widening Standard 0.22mm at 528mm?
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Will L
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Re: Society Gauge Widening Tool
Julian Roberts wrote:...I may sound a bit like Jeremy Paxman in his famous interview with Michael Howard where he asked the same question 14 times. I don't think anyone has an answer though...?
Why is our Gauge Widening Standard 0.22mm at 528mm?
I don't think anybody will be able to tell you why, because it is clearly arbitrary, and I would argue (have been arguing) more to do with emulating the prototype than any real operational necessity. In any event it could only have any practical meaning if the minimum degree of lateral flexibility available over a given wheelbase is also specified.
On the prototype, if I am not much mistaken, there is little or no lateral flexibility on most axle boxes, so getting a rigid multi axle chassis round anything but the gentlest curves required gauge widening, particularly given the prototype's tendency to destroy the track if pushed closed to the limit. Even then gauge widening was limited to two (arbitrary?) steps and was accompanied by specific speed restrictions / total prohibitions by loco type and curve radius.
Small scale model railways have always been given to running express speeds round impossibly small radius curves and that is down to the un-prototypical provision of lateral flexibility, and the fact that track and following services are not at risk.
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Julian Roberts
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Re: Society Gauge Widening Tool
Will L wrote:Julian Roberts wrote:...I may sound a bit like Jeremy Paxman in his famous interview with Michael Howard where he asked the same question 14 times. I don't think anyone has an answer though...?
Why is our Gauge Widening Standard 0.22mm at 528mm?
I don't think anybody will be able to tell you why, because it is clearly arbitrary, and I would argue (have been arguing) more to do with emulating the prototype than any real operational necessity. In any event it could only have any practical meaning if the minimum degree of lateral flexibility available over a given wheelbase is also specified.
On the prototype, if I am not much mistaken, there is little or no lateral flexibility on most axle boxes, so getting a rigid multi axle chassis round anything but the gentlest curves required gauge widening, particularly given the prototype's tendency to destroy the track if pushed closed to the limit. Even then gauge widening was limited to two (arbitrary?) steps and was accompanied by specific speed restrictions / total prohibitions by loco type and curve radius.
Small scale model railways have always been given to running express speeds round impossibly small radius curves and that is down to the un-prototypical provision of lateral flexibility, and the fact that track and following services are not at risk.
Hi Will
Well...Surely the basic standard amount of GW was an average out of wheelbases? Thus LT track was narrower with less widening as all the stock is 4 wheel bogies. This is on the original Protofour "New Approach to Modelling Standards" http://www.norgrove.me.uk/history_files ... RN8-66.htm
At the other extreme LTE straight track is normally gauged at 4ft. 83/8 in. and widened on curves to 4ft. 8½ in., but this is a special case where long inflexible wheelbases are not found.
Just found this on http://www.norgrove.me.uk/history_files ... RN9-66.htm - the original Protofour "A New Approach to Modelling Standards".
With BB spacing plus twice the tyre width, it can be seen that the clearances between axleguards are almost the same as EM Gauge. This feature, combined with gauge widening, means that there are no greater restrictions on minimum radius curves than in the present EM Gauge.
My EM gauge triangular track gauge is 31mm long.
It is what I was saying as speculation a few days ago. Dunno how I missed this. Probably I had and was regurgitating the thoughts, thinking they were my own.
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Will L
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Re: Society Gauge Widening Tool
Julian Roberts wrote:Well...Surely the basic standard amount of GW was an average out of wheelbases?...
Don't know what you mean. Given that on the prototype there are two variables in play (Wheelbase and track curvature), gauge widening puts an upper limit to the minimum curve any given wheelbase rigid 3+ axle vehicle would go round. How can that be described as an average?
..Thus LT track was narrower with less widening as all the stock is 4 wheel bogies.
Actualy LT had no gauge widening (as none is required for 4 wheel vehicle/bogies), but narrowed their track on the strait, which they could well have done to restrict any tendency for their bogies to hunt.
This is on the original Protofour "New Approach to Modelling Standards" http://www.norgrove.me.uk/history_files ... .htm'''....
...Just found this on http://www.norgrove.me.uk/history_files ... RN9-66.htm - the original Protofour "A New Approach to Modelling Standards".
Neither of these show any sign that gauge widening was been given any thought beyond sort of reproducing mainline prototype practice as I suggested.
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Julian Roberts
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Re: Society Gauge Widening Tool
Neither of these show any sign that gauge widening was been given any thought beyond sort of reproducing mainline prototype practice as I suggested.
Hi Will
No time to try to understand how it is neither of us is understanding the other just now.
But there is plenty of thought about gauge widening in the original Protofour article
http://www.norgrove.me.uk/history_files ... RN8-66.htm
While discussing flangeways, it might be opportune to mention that prototype flangeways are not necessarily of equal value. The crossing flangeway is always set at 1¾ in., and this spacing is maintained permanently by bolting the rails together with spacing blocks, or by special chairs. However, with gauge widening on curves, and with the check rail set only in relation to the outer running rail, the flangeway between the check rail and the adjacent running rail is simply the difference between the Track Gauge and the Check Gauge at that particular point.
On prototype tracks the gauge is deliberately widened on curves, those less than 5½ chains radius having an increase of ¾in. to 4ft. 9¼ in. At the other extreme LTE straight track is normally gauged at 4ft. 83/8 in. and widened on curves to 4ft. 8½ in., but this is a special case where long inflexible wheelbases are not found. Both gauge widening and fixed and variable flangeways are a feature of Protofour operations.
The EEM experiments aimed at controlling running conditions by checks made with only two gauges; while this was perhaps too optimistic, it was nonetheless, very close to the truth. Completely reliable operations in any model railway system require the control of five dimensions :-
1. Both wheel and rail contours must be matching sets for the standards in use.
2. Wheel spacing on axle (BB) must be correct.
3. Track Gauge (TG) must not be less than the nominal value, and should include a gauge widening factor for curved track.
4. Check Gauge (CG) measured from the face of the check rail to the face of the outer running rail, must not be less than the nominal value.
5. Crossing Flangeway (CF) between the wing rails and the vee at a crossing, must be a specified value.
Once again it will be seen that the wheel and rail contours determine the remaining dimensions.
But fascinatingly the original table of P4 dimensions includes no reference to the radius at which the scaled down prototype GW of 0.25mm, reduced by the P4 12% to 0.22mm, comes into play. No mention of 528mm. The article was in the August 1966 Model Railway News
The "at 528mm" does not appear till the January 1967 article http://www.norgrove.me.uk/history_files/mrc1/Pt1.htm
The choice of the radius at which full gauge widening comes into play is the point of our discussion.
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Julian Roberts
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Re: Society Gauge Widening Tool
For some reason the link doesn't work for the original article August 66. Its on Grosvenor Sidings website. Not sure if its on Society website - surely it must be...
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John McAleely
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Re: Society Gauge Widening Tool
Julian Roberts wrote:For some reason the link doesn't work for the original article August 66. Its on Grosvenor Sidings website. Not sure if its on Society website - surely it must be...
Both of the links in your posting above work for me:
http://www.norgrove.me.uk/history_files ... RN8-66.htm
http://www.norgrove.me.uk/history_files/mrc1/Pt1.htm
One at least appears to be an 'August 66' article. So I'm not sure what problem you refer to.
Which parts are on Keith's site, and which on the society site are lost somewhere in the accidents of history. In the long run, I'm perfectly happy to host them on the society's website.
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Armchair Modeller
Re: Society Gauge Widening Tool
The "at 528mm" does not appear till the January 1967 article http://www.norgrove.me.uk/history_files/mrc1/Pt1.htm
528mm is only 20.8 inches. Surely well below the radius most people would seriously consider in P4 - except perhaps on an industrial siding or a tramway? Even in 2mm scale, 24" (600mm) is the minimum recommended radius for main lines.
528mm is only 20.8 inches. Surely well below the radius most people would seriously consider in P4 - except perhaps on an industrial siding or a tramway? Even in 2mm scale, 24" (600mm) is the minimum recommended radius for main lines.
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Julian Roberts
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Re: Society Gauge Widening Tool
Armchair Modeller wrote:The "at 528mm" does not appear till the January 1967 article http://www.norgrove.me.uk/history_files/mrc1/Pt1.htm
528mm is only 20.8 inches. Surely well below the radius most people would seriously consider in P4 - except perhaps on an industrial siding or a tramway? Even in 2mm scale, 24" (600mm) is the minimum recommended radius for main lines.
OK Armchair. Now you are asking the Jeremy Paxman question for me. Great. We all need to ask because none of us know. So I am going to create a new thread asking the question but asking people to answer here. Just in case anybody doesn't know I have been asking the question since the beginning of the thread, in February.
Because since my post to you on Saturday I have come up with an answer, but I really want to test out whether there really is no other answer, whether really no one can answer the question, of all the experts on this forum.
So let's get this framed exactly. The question is, why did the MRSG choose 528mm to be the radius at which the prototypical gauge widening of 0.25mm, reduced by the P4 12% to 0.22mm, came into play? Why did a group whose whole ethic was an almost exact scale reduction of everything - any deviations being by no more than 12% - choose a radius that is so wildly out of kilter, at least halving the prototype radius?
Last edited by Julian Roberts on Wed Aug 17, 2016 12:51 am, edited 1 time in total.
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Julian Roberts
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Re: Society Gauge Widening Tool
Will
Right at the beginning of this thread Philip Hall said
I looked up this Fast Track and it said that it did two versions; the 0.2mm wider was for curves as this made it easier for the trains to run through them. It seems to have disappeared now from the C&L website. But the point is, surely this is the function, and we don't need to completely do our heads in trying to understand it beyond that. The prototype widening is tiny, 3/4 inch max.
I think we are going round in circles. Surely all vehicles had in their specification the minimum radius they would take. Gauge widening is very little to do with that. It is just to do with easing the way as in Iain Rice's diagram, for long wheelbase vehicles especially, even if just 4 wheeled - like Pacers for example.
My point in all this is that this easing of the way will make vehicles less likely to derail. We have said all this.
Well, there was gauge widening on LT at the time the MRSG were writing the original document - it says the gauge is narrow as you say, but there is still 1/8th widening on curves.
The MRSG seems to me to be saying in the original August 1966 article that the gauge widening is important, that is why it says the track gauge incorporates a Gauge Widening Factor. What isn't specified there is what that Factor is, and what is astonishing is that they then chose a factor that gives a radius of 528mm - 20 inches as Armchair says, or 3rd radius Peco Setrack if I remember correctly from my 00 gauge kids' layout days - for maximum gauge widening, when the prototype maximum was at 1452mm, 4 foot 9 inches.
Part of the whole issue is, how did they translate the stepped increase of the gauge on the prototype into an easy to use triangular gauge? The maths is fearsomely complicated. With our mobile phones we can do anything practically, but in those days probably a machine the size of a clothes washer was required to do such sums as this: here is the formula for working out the gauge widening - and this is for just one figure:
Right at the beginning of this thread Philip Hall said
For myself, my new layout will, on the main lines at least, use the Exactoscale Fast Track bases (soon to be released as ready to lay track, apparently) in both the gauge widened and standard forms. I believe the gauge widened version is 0.2mm wider.
I looked up this Fast Track and it said that it did two versions; the 0.2mm wider was for curves as this made it easier for the trains to run through them. It seems to have disappeared now from the C&L website. But the point is, surely this is the function, and we don't need to completely do our heads in trying to understand it beyond that. The prototype widening is tiny, 3/4 inch max.
I think we are going round in circles. Surely all vehicles had in their specification the minimum radius they would take. Gauge widening is very little to do with that. It is just to do with easing the way as in Iain Rice's diagram, for long wheelbase vehicles especially, even if just 4 wheeled - like Pacers for example.
My point in all this is that this easing of the way will make vehicles less likely to derail. We have said all this.
Actualy LT had no gauge widening (as none is required for 4 wheel vehicle/bogies), but narrowed their track on the strait, which they could well have done to restrict any tendency for their bogies to hunt.
Well, there was gauge widening on LT at the time the MRSG were writing the original document - it says the gauge is narrow as you say, but there is still 1/8th widening on curves.
At the other extreme LTE straight track is normally gauged at 4ft. 83/8 in. and widened on curves to 4ft. 8½ in.
The MRSG seems to me to be saying in the original August 1966 article that the gauge widening is important, that is why it says the track gauge incorporates a Gauge Widening Factor. What isn't specified there is what that Factor is, and what is astonishing is that they then chose a factor that gives a radius of 528mm - 20 inches as Armchair says, or 3rd radius Peco Setrack if I remember correctly from my 00 gauge kids' layout days - for maximum gauge widening, when the prototype maximum was at 1452mm, 4 foot 9 inches.
Part of the whole issue is, how did they translate the stepped increase of the gauge on the prototype into an easy to use triangular gauge? The maths is fearsomely complicated. With our mobile phones we can do anything practically, but in those days probably a machine the size of a clothes washer was required to do such sums as this: here is the formula for working out the gauge widening - and this is for just one figure:
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Martin Wynne
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Re: Society Gauge Widening Tool
Copying this here from your other topic, as requested. I can't believe this has been going on for 6 pages. It doesn't matter a damn who put those figures in the standard, because they are just plain wrong, and should be ignored.
__________________________
Hi Julian,
528mm is 2 chains radius (scale).
You have to remember that those dimensions were compiled over 40 years ago, when prototype info wasn't so widely known. If you read the old articles you can find several questionable details quoted. If you are looking for perfection in some of the early standards you will be disappointed. For example you can see switch back clearance quoted as 3" (1mm) when it should be 2"(0.67mm).
My guess is that someone had some pre-group info relating to gauge-widening on a specific company, where 2 chains was the bottom limit. Also the 3/4" maximum widening was not always so -- in some cases 5/8" or 11/16". For example on LPTB lines where main line locos also run, max gauge (below 5.1/2 chains radius) was 4ft-9.1/8in, i.e. 5/8" widening over standard gauge.
I think you are looking for an explanation which doesn't exist -- the standard is just plain wrong, that's all there is to it. More to the point, what is your actual modelling problem?
Note that the model 3-point gauge has no prototype equivalent. Check rail chairs were made in a series with increasing flangeways, typically 1/4" increments. So gauge-widening had to be one of those steps and fixed. It wasn't infinitely adjustable, except where there was no check rail -- which wasn't often because curves under 10 chains radius on passenger lines are required to be fitted with a continuous check rail.
regards,
Martin.
__________________________
Hi Julian,
528mm is 2 chains radius (scale).
You have to remember that those dimensions were compiled over 40 years ago, when prototype info wasn't so widely known. If you read the old articles you can find several questionable details quoted. If you are looking for perfection in some of the early standards you will be disappointed. For example you can see switch back clearance quoted as 3" (1mm) when it should be 2"(0.67mm).
My guess is that someone had some pre-group info relating to gauge-widening on a specific company, where 2 chains was the bottom limit. Also the 3/4" maximum widening was not always so -- in some cases 5/8" or 11/16". For example on LPTB lines where main line locos also run, max gauge (below 5.1/2 chains radius) was 4ft-9.1/8in, i.e. 5/8" widening over standard gauge.
I think you are looking for an explanation which doesn't exist -- the standard is just plain wrong, that's all there is to it. More to the point, what is your actual modelling problem?
Note that the model 3-point gauge has no prototype equivalent. Check rail chairs were made in a series with increasing flangeways, typically 1/4" increments. So gauge-widening had to be one of those steps and fixed. It wasn't infinitely adjustable, except where there was no check rail -- which wasn't often because curves under 10 chains radius on passenger lines are required to be fitted with a continuous check rail.
regards,
Martin.
40+ years developing Templot. Enjoy using Templot? Join Templot Club. Be a Templot supporter.
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LesGros
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Re: Society Gauge Widening Tool
Julian wrote:
My guess is that "they" didn't. The triangular-form gauge was introduced as an improvement on the earlier rectangular gauge of similar effective size; it certainly provides access to more rivets with a soldering iron. I suspect that it was noticed or maybe realised intuitively, that both could be used to give a useful amount of gauge widening on curves (or unwanted narrowing if the triangle is used incorrectly) on typical P4 layouts. It is not a big step to imagine that a comparison calculation was subsequently made for the impossibly tight radius of 528mm, and added to the table later.
Julian,
Really? The hard bit about versine calculation is understanding the trigonometry well enough to be able to set out the required formulae. However, for us, the versine calculation is "just a matter of plugging-in the numbers" as my maths tutor put it. Furthermore, In "those days" such calculations were, and can still be made, with the aid of a set of trig tables, or a slide rule.
Clothes-washer sized computer? - not required.
...Part of the whole issue is, how did they translate the stepped increase of the gauge on the prototype into an easy to use triangular gauge? ...
My guess is that "they" didn't. The triangular-form gauge was introduced as an improvement on the earlier rectangular gauge of similar effective size; it certainly provides access to more rivets with a soldering iron. I suspect that it was noticed or maybe realised intuitively, that both could be used to give a useful amount of gauge widening on curves (or unwanted narrowing if the triangle is used incorrectly) on typical P4 layouts. It is not a big step to imagine that a comparison calculation was subsequently made for the impossibly tight radius of 528mm, and added to the table later.
...The maths is fearsomely complicated. With our mobile phones we can do anything practically, but in those days probably a machine the size of a clothes washer was required to do such sums as this: ...
Julian,
Really? The hard bit about versine calculation is understanding the trigonometry well enough to be able to set out the required formulae. However, for us, the versine calculation is "just a matter of plugging-in the numbers" as my maths tutor put it. Furthermore, In "those days" such calculations were, and can still be made, with the aid of a set of trig tables, or a slide rule.
Clothes-washer sized computer? - not required.
LesG
The man who never made a mistake
never made anything useful
The man who never made a mistake
never made anything useful
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Julian Roberts
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Re: Society Gauge Widening Tool
Martin Wynne wrote:Copying this here from your other topic, as requested. I can't believe this has been going on for 6 pages. It doesn't matter a damn who put those figures in the standard, because they are just plain wrong, and should be ignored.
__________________________
Hi Julian,
528mm is 2 chains radius (scale).
You have to remember that those dimensions were compiled over 40 years ago, when prototype info wasn't so widely known. If you read the old articles you can find several questionable details quoted. If you are looking for perfection in some of the early standards you will be disappointed. For example you can see switch back clearance quoted as 3" (1mm) when it should be 2"(0.67mm).
My guess is that someone had some pre-group info relating to gauge-widening on a specific company, where 2 chains was the bottom limit. Also the 3/4" maximum widening was not always so -- in some cases 5/8" or 11/16". For example on LPTB lines where main line locos also run, max gauge (below 5.1/2 chains radius) was 4ft-9.1/8in, i.e. 5/8" widening over standard gauge.
I think you are looking for an explanation which doesn't exist -- the standard is just plain wrong, that's all there is to it. More to the point, what is your actual modelling problem?
Note that the model 3-point gauge has no prototype equivalent. Check rail chairs were made in a series with increasing flangeways, typically 1/4" increments. So gauge-widening had to be one of those steps and fixed. It wasn't infinitely adjustable, except where there was no check rail -- which wasn't often because curves under 10 chains radius on passenger lines are required to be fitted with a continuous check rail.
regards,
Martin.
Martin
Interesting.
I infer from this that if the standard is wrong, the triangular tool is the wrong length.
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Julian Roberts
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Re: Society Gauge Widening Tool
Should have added yesterday, the answer to the riddle or the Jeremy Paxman question is already on this thread. But I didn't see it because I only had my Society rectangular gauge Tool 29.75mm length to go on.
But the real theoretically correct length (to give 0.22 widening at 528mm) is 31mm, as I have already said on this thread - that figure is clarified on the spreadsheet.
But the real theoretically correct length (to give 0.22 widening at 528mm) is 31mm, as I have already said on this thread - that figure is clarified on the spreadsheet.
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Armchair Modeller
Re: Society Gauge Widening Tool
Julian Roberts wrote:
So let's get this framed exactly. The question is, why did the MRSG choose 528mm to be the radius at which the prototypical gauge widening of 0.25mm, reduced by the P4 12% to 0.22mm, came into play? Why did a group whose whole ethic was an almost exact scale reduction of everything - any deviations being by no more than 12% - choose a radius that is so wildly out of kilter, at least halving the prototype radius?
The problem, Julian was that your question could innocently be interpreted in two completely different ways. I think we all assumed that it was specifically about the amount of widening. Your latest comment finally make it clear that it was the 528mm figure you were querying - why not a more realistic figure like 3ft or 4ft radius, for example?
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