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Thread: Flange-ways in our Turnouts

  1. #1
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    Default Flange-ways in our Turnouts

    While researching this subject recently, of 'excessive size flangeways' in commercially available turnouts, I was finding lots of really interesting discussions scattered about the internet and multiple railroad forums. I was running out of bookmarks to try and recall all of them. That prompted me to start this subject thread to try and bring a lot of those discussions, links and photo references into one central subject thread that I could revert back to when I failed to remember some particular posting on specific 'derailment problems' of our turnouts.

    Naturally it is not just problems with the turnouts nor the wheels themselves individually. Its a 'system' of the two.

    So I thought this posting was rather interesting to start the subject thread out,...
    http://www.ostpubs.com/systems-thinking/


    The following is an excerpt from The Missing Conversation Vol. 03, coming Jan. 1, 2013.

    As John Armstrong notes in his classic book: The Railroad-What It Is, What It Does, it is futile to argue which was more important, a track system of rails, flanged wheels or the concept of coupling multiple cars together to form a train. All three taken together make up the most significant system of technology in the history of transportation to date: applying the heat energy output of a machine to transcend the capacity of animal power in moving cargo.



    Wheels
    A prototype wheel looks deceptively simple at first glance, yet it is anything but. Full size train wheels have a number of functions to perform, with millions of dollars of freight and many lives riding on the outcome. Railroad wheels and track are a complex, integrated system that is carefully monitored and maintained for the safety of all concerned. As we’ll see, standards are critically important.

    The beginning
    The earliest railroad wheels were little more than modified wagon wheels that were sufficient to carry the lightweight railroad cars of the day. Although spoked wheel designs in both wood and metal were quite common, they soon proved unsuitable and were replaced by wheels having a disk design, typically of cast iron, which was easily worked by the metal smiths of the era. These designs evolved into the wheels we know today.

    Cast iron tends toward brittleness and foundry men discovered that an extremely hard chill developed in the iron if it was poured next to another iron surface. This chilled area, as deep as an inch, could not be machined and was typically avoided. However, it proved ideal for the wear surface on freight car wheels. Therefore the rim and flange were poured as a unit against an iron ring, leaving the interior and hub areas soft and machinable.

    Other considerations
    You would think things like wheel diameter, tire width and flange depth appear straightforward enough, yet such was not the case initially.

    Take the diameter for example. Larger wheels provided a better ride but added to the dead weight of the car. They were more expensive too, an important consideration given the ultimate number of wheels required by any line.

    From what is known, a diameter of 36 inches appears to have been an early standard for freight cars. However, roads like the B&O used smaller 30 inch wheels on certain cars in the 1830s progressing in size to 31 inches, even though a compromise of diameter of 33 inches was widely accepted in America by the 1840s.

    Gauging the impact of interchange
    Early railroads were essentially closed systems. The trains of one line typically didn’t travel on competing lines and passengers and freight were manually transferred at end points or junctions. As rail travel and shipping of freight became more widespread, this cumbersome process began to fall apart. With manual transloading being horribly inefficient, the superiority of having cars able to travel freely from point to point soon became clear. Yet there was a huge problem looming: track gauge was anything but universal.

    The interchange of freight cars among competing rail lines was unprecedented in American business history. It worked because everybody benefitted, either by increased efficiency, lower costs or both. The fly in the ointment was the wide variety of track gauges used in the United States at this time. Driven by local political interests, hubris among the “empire builders”, greediness in keeping traffic confined to their system or just an urge to be different, track gauge standards were all over the place. Pioneered by brothers George and Robert Stephenson, the Stephenson gauge of 4’ 8.5” was commonly used, accounting for over 50 percent of track miles in 1861, with the 4’10” gauge common in the states of Ohio and New Jersey only accounting for 9.9 percent. In the American South, five feet was the common standard comprising 21.9 percent of total miles of track, while the Erie Railroad’s famously broad gauge of six feet only represented a mere 5.3 percent.

    Think that’s wide? A line in Missouri used 6’ 6” as their gauge for reasons no one understood. Rail lines in between these extremes used a gauge of 4’9” in an attempt to compromise the differences between the Stephenson gauge and 4’ 10”. Given the extent of trackage laid, compromise solutions to the problems of interchange abounded. Some were more laughable than others.

    One stop-gap idea widely adopted for a time was an extra wide wheel tread that could traverse tracks laid to 4’-8.5” up to 4’10”. This proved to be ill-conceived at best because the running qualities of these wheels were horrible, due to the fact they didn’t conform to either gauge. By necessity the wheel flanges had to be gauged to the narrowest track leaving a lot of side-to-side slop on the wider gauges. Cars so equipped could only be moved at slow speeds and, while freight might withstand some jostling around, passengers were less tolerant. Suffice to say that railroad men hated these things.

    Other schemes such as exchanging trucks, multi-gauged track composed of three and, in one case, four rails were all tried but the only solution that was going to work efficiently was to adopt a standard track gauge dimension. With miles of track already laid many lines were resistant to regauging their track, yet the handwriting was on the wall and all lines eventually adopted the Standard Gauge of 4’ 8.5”. Finally, a car could travel from one part of the country to another without the problems of delay from transloading, switching trucks and other impediments.
    That's some interesting history I was unaware of, or had forgotten
    Last edited by beiland; 02-01-2018 at 02:29 PM.

  2. #2
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    Default Systems Thinking

    a followup by Mike....


    As the excerpt from TMC 03 conveys, track and wheels are an integrated system: in essence, two sides of the same coin and this relationship is just as true for our models as for the prototype. One cannot alter one part of the equation without impacting the other.



    The P48 wheels and track shown above, illustrate this interdependent relationship of how the frog and guardrails work in combination with the wheel profile to guide the truck safely through the turnout. Notice in particular how the wheel is completely supported by the frog as it bridges the gap of the flangeway.This is just as critical in model form as it is on the prototype. The system is made of the width of the tire, the depth and thickness of the flange; the shape of the fillet where the flange transitions into the tire and the back-to-back distance between the inside faces of the wheels. These are complimented by the track components such as the shape of the rail head, which matches the shape of the tire, the width of the flangeways at the frog and guardrails, plus the back-to-back distance between these two.

    A solution often promoted in O scale is to finally adjust the track gauge to proper dimensions but keep the existing coarse standards for wheels and flangeways. The thinking presumably is that this will allow all the existing legacy equipment built to five foot gauge to still have a place (just swap out the trucks and some drive wheels). Further claims are that it also allows modelers to decide for themselves whether to keep the legacy standards or adopt P48 for the sake of consistency.

    Here’s why I think this is a bad idea: A compromise is a compromise is a compromise. This is the situation in HO now. HO has one track gauge yet it also has multiple options for wheel specs such as the RP25, Code 88 semi-scale and P87 proto-scale.



    Look closely at this image of P87 wheels on a regular HO scale Shinohara turnout. There are a multitude of problems here. Even though the track gauge is acceptable for P87, the flangeways are not. While the grossly oversized flangeways work with the out-of-scale NMRA wheels they were designed for, the P87 wheels have nothing to support or guide them through the frog. Notice the huge gap between the wheel face and guardrail on the left. Why is it so huge? Because the back-to-back dimension is vastly different between P87 and the NMRA standard. By reducing the width of the wheel tread and thickness of the flange to scale dimensions, the back-to-back distance is also widened. Do you see how interdependent all these relationships are and why changing just one aspect affects all the others?

    Notice further how the wheel on the frog has fallen into the gap created by the wide flangeway, instead of being supported by the wing rail as it should be. The semi-scale Code 88 wheels that are becoming more popular in HO are not designed to this flangeway either. While they don’t drop into the gap completely, there is a noticeable bump when traversing certain brands of turnouts. Like the compromise attempt of the extra wide tires used by the prototype, such compromised solutions on our models are only marginally effective. Our models, like the prototype are made up of systems. It’s all or nothing, pick your standards and be consistent.

    Why
    Why does this matter to us as modelers? I believe that fine scale modeling is the visible outcome of a journey that starts with the prototype. A modeler starts with a closer examination of the prototype and, as a result, gains a more thorough knowledge of the components and how they work together. With that knowledge comes greater clarity of how compromised many aspects of our models have become over time. From that point I believe a decision has to be made: Accept the out-of-scale features for the compromise they are or continue the journey wherever it leads.

    I understand that many folks are happy with such compromises for the simplicity of building with readily available products or the savings in time they offer. For my modeling such visual discrepancies ruin the effect I want to achieve. For me, such details matter a great deal. I believe it’s important that a model be consistent in scale from the rails to the running board, which is why I choose to follow the path wherever it leads.

    Regards,
    Mike
    Last edited by beiland; 02-01-2018 at 02:31 PM.

  3. #3

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    I understand that many folks are happy with such compromises for the simplicity of building with readily available products or the savings in time they offer. For my modeling such visual discrepancies ruin the effect I want to achieve. For me, such details matter a great deal. I believe it’s important that a model be consistent in scale from the rails to the running board, which is why I choose to follow the path wherever it leads.
    I first noticed the "problem" when using KATO code 83 Uni-track, maybe five years ago. even BB era box cars with sprung trucks were doing a "dance" over a #6 frog. I build in Code 70, primarily because I like the overall appearance. I use mostly Micro Engineering #6 switches throughout the layout. While there is no real pattern, just about every movement has frog hopper, and as long as nothing picks a switch or climbs a frog, I'm good. Operating over the Penn Central warps my perception of track work, even in HO Scale.

    Seriously, short of building our own switches, there is no alternative other than to use what we have to work with. We can close the flangeways on the guard rail, but that will create problems with RP25 wheels. Frankly, my biggest derailment problem on switches, is caused by points that open up under movement. usually, that is because of some unseen pressure point causing the point to spring out of place. I agree, no one wins when we compromise, and much depends on what level of operating you are looking for. I lack the patience and vision to build to fine scale standards, which Is why I tend to avoid Code 88, and Proto 87 wheels. I have to accept my limitations also. However, I do understand your point, and at least partially agree.

    Boris
    No Whimpering!

  4. #4
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    Default How Wheels Roll thru a Frog Point

    This is a very good visual presentation of how our wheels roll thru a frog point. It was done up by Fast-Track



    I believe there were a few others, but I can't find them at the moment.

  5. #5
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    Default

    This is a mediocre visual that includes older switch tower operation,...
    Last edited by beiland; 02-03-2018 at 07:19 AM. Reason: emphasis mediocre as to our subject matter

  6. #6

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    This is an interesting post. I have seen a number of people remarking about having problems with the flangeways in frog. I guess that I am lucky because I have never experienced and problems at all with them. My track is all code 70, either hand laid or Shinohara. All the wheels on my freight equipment have metal wheels from either Kadee, Intermountain or Proto 2000 and cars all run smoothly through any of my turnouts, hand laid or the Shinohara.

    In this video, the frog is in about the center of the screen and there is little or no movement of the cars as they pass over the frog.

    ................................ Chet


    Video - Switching in Churchill - https://www.youtube.com/watch?v=YR-tYl9fd9s
    VIDEO Tour of the layout - https://www.youtube.com/watch?v=qiNqrkq9xYY
    New cab ride - https://www.youtube.com/watch?v=QiL7SgH6Wbw

  7. #7
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    Default Mechanical aspects vs Electrical aspects

    If we momentarily disregard the electrical aspects (shorting, DCC friendly or not, etc), then primarily we need to look at the depth of the flangeways (particularly at the frog point), and the width of the flangeways (both at the frog point, and the guide/safety rails).

    DEPTH of Flangeway:
    Most of us know that the European trains, and some of our early American ones had rather big flanges on their wheels. The commercial turnout builders had to provide rather deep flangeways to accommodate these larger flanges. Many European makers still continue to provide such designs to accommodate their clients. USA makers have been modifying their turnouts to adjust to the wide acceptance of much smaller wheel flanges, and increased us of smaller code rail.

    Thus we Americans now see a significant decrease in flangeway depths at the frog. Some have even argued for such shallow flangeway depths as to allow the wheel flanges to roll UPON them for the short distances in the area of 'just prior' to the frogs points. This might seem like a good idea at first (some even suggesting shimming up this 'valley' in older turnouts to prevent the wheel from dropping into this 'cravice'), but there are dangers here also.

    BTW there is another subject thread on this forum that has some members running experiments and measurements with this subject of flangeway depth / wheel flange size,...

    Bone-headed move to RP25

    ...and on page 7
    Quote Originally Posted by NP2626 View Post
    I took 16 readings off of various manufactured wheel sets and found the flange depths to be consistently around .025 deep. Variation ran from .024 to .030, however, the .030 reading was taken from a Varney Docksider (Little Joe) which is possibly older than 60 years. So RP-25 is older than July of 2009, the latest revision.

    Making a pad for the bottom of the frog flange-way that is .020 thick, per how Willie is doing it would seem the correct way to fix the dip into the frog that cars and locomotives do. My guess is that Atlas made this depth to handle the older cars and locomotives which had the old Pizza Cutter Flanges and never corrected the frog to fit the new standards. Nobody complained, so the squeaky wheel never got greased!

    WIDTH of Flangeways:
    Here we two areas of consideration, 1) the width of the flangeways at the outer tracks, and 2) the width of the flangeways at the inner areas next to the frog point (often referred to the 'wing rails). Both of these areas are very important to help our train wheels/trucks get thru our turnouts in the best manner. In both cases it is general most desirable that these 'sometimes broad width' flangeways be restricted in width as much as possible WITHOUT undue restriction to the smooth passage of the wheel flange thru the turnout.

    Please remember here that we DO NOT want to look at this situation while considering just a single axle passing thru, but rather a 'truck' of axles that is likely 2 or 3 axles strung together, and likely in a 'rigid form'.

    ...some illustrations
    Click image for larger version. 

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    Click image for larger version. 

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    ....this guideway shimming is often suggested for Peco turouts
    Last edited by beiland; 02-03-2018 at 08:31 AM.

  8. #8

    Default

    Just FYI I have mostly Peco Code 83 Streamline turnouts (#5, #6 and #7 "curved") and I have no problems with them at all.

    Frederick

  9. Default

    I just don't seem to have all these problems. I have my own hand-laid turnouts of various kinds, Peco Streamline Code 83 #6's in large numbers, and some Walthers/Shinohara curved turnouts that are Code 83 and have either #7.5 or #8 frogs. I have had some shorts with steamers at the frogs of the curved turnouts, which I took care of by cutting a second gap about 0.25" further out than their plastic spacer. For example, the BLI T1 Duplex is not articulated. It resembles the prototype in all details except that the two center driver axles are blind...no flanges. On the #7.5 turnouts, when the blind drivers' tires cross over the frogs, they want to drift inward along the curve and in doing so they make momentary contact with the wrong frog rail. But I've' not had problems picking frog points on any of my turnouts, and I have a wide array of rolling stock.
    Crandell

  10. #10
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    Default

    It does appear that Code 83 users have less problems, as these came along after the Code 100 rail products, and since most were targeted at the American market, there were adjustments made in the design of them.

    Are there many (any) European track/turnout manufactures supplying Code 83 stuff (other than Peco).

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