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Track Standards

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Track Standards
Posted by riogrande5761 on Monday, June 15, 2020 10:53 AM

SeeYou190
I have a very hard time communicating my tone in things I type on this forum. I once responded to a question about figure painting, and got about a half dozen "why are you so angry" responses.

It's true, typed message often convey or don't convey what was intended by the author.  Emoticons were invented partly to help in that regard.  And to be fair, communicating in ways to overcome lack of facial or body language can be a challege on forums and in emails.  It can take extra effort to avoid being misconstrued.  It a can be learned but even then unintended consequences still happen.  Black Eye

Re: Track standards and John Armstrongs book, things have evolved in the hobby since Track Planning for Realistic Operations was last revised, but much of the information is still fundementally sound and worth digesting and putting into action.  Very much worth reading.

Very true. When I tell some people I am using 24 inch as the minimum radius for hidden and branchline track, I get the "that is pretty darned sharp curve" response. Our perception of tight curves has certainly changed. -Kevin

It has, but curves need to taken in context too.  For those running shorter rolling stock, 24 inches may be totally fine.  OTOH, those running 89' auto-racks or flat cars or 85' passenger equipment, may be less than happy with 24-inch curves.

John Armstrong does discuss those kinds of compromises in his book and that full length passenger cars (very much relevant in his time too) may need modifications or special consideration if to be reliably run on 24-inch curves.

I've read that Walthers passenger cars, even though the recommended minimum radius is 24-incyes, it is reported they don't work very well on those curves and many recommend 30" radius or more. 

A growing number of modelers are interested in post-1990 model trains and as a rule, the models are longer, engines and freight cars both.  So there is justification for conventional curves to be larger than they used to be, being bumped up from 24 inches to 28 or 30 inch radius.

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Posted by IRONROOSTER on Monday, June 15, 2020 11:35 AM

I'm not sure changing the definition of very sharp/sharp/conventional/broad would be helpful. 

First, who is going to set the definition and maintain it as necessary.

Second, it will be confusing because older models/articles and newer models/articles will be using different values which will confuse buyers/readers.

Interestingly, the NMRA RP11 for curvature has 13 different classes of curves for model railroads.

When discussing curves, I think a lot of us tend to forget that a lot of folks have small layouts.  The hobby press is full of large layouts.  But I suspect there a lot of casual hobbyists who have a 4x8 or little larger. For them the current definitions are good.

For those of us a little more involved, perhaps we should the RP 11 definitions and call our curves Class F or L or P, etc.

Paul

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Posted by riogrande5761 on Monday, June 15, 2020 11:54 AM

IRONROOSTER

I'm not sure changing the definition of very sharp/sharp/conventional/broad would be helpful.

Yes true.  And for that matter, why would John Armstrong even set such a labeling scheme in the first place?  (Sharp, Conventional, Broad).  Conventions of the time.

My only point is that what some consider to be sharp, conventional or broad has changed a bit over time.  If any terminology is meaningless to you, well, blame John Armstrong for bringing it up in the first place - he was very naughty! 

Never-the-less book and much of the content is still very useful.  His discussion on "squares" didn't really work for me either, so I discarded that part.  Not every part of Track Planning for Realistic Operation will be useful to everyone, but a lot of it will be.  

First, who is going to set the definition and maintain it as necessary.

Second, it will be confusing because older models/articles and newer models/articles will be using different values which will confuse buyers/readers.

Interestingly, the NMRA RP11 for curvature has 13 different classes of curves for model railroads.

To answer the first question, apparently JA had the audacity to set the definition.  But since he is no longer alive, he cannot maintain or justify it, apart from what he wrote in the book.

When discussing curves, I think a lot of us tend to forget that a lot of folks have small layouts.  The hobby press is full of large layouts.  But I suspect there a lot of casual hobbyists who have a 4x8 or little larger. For them the current definitions are good.

For those of us a little more involved, perhaps we should the RP 11 definitions and call our curves Class F or L or P, etc.

Paul

As I mentioned to Keven, the question of curve radii boils down to application.  Obviously the smaller the layout and/or space, the more curve radii will be limited.  Also, when operating shorter rolling stock, curve minimums can be tighter and still work well.

When person comes here and discusses buidling a 4x8 layout or something close to that in size, I still would ask what they are planning to run and even if not long cars, there may be a possibility they may wish to run longer rolling stock in the future.  Thus, if they can increase the size of the layout a few inches, at least they could, perhaps used 22 and 24 1/2 inch curves (if a double track oval) rather than 18 and 22 inch curves, and that would allow perhaps full length passenger cars or longer freight cars to still operate without major issues. It's only a small increase but could yield dividends in operation possibilities.

So maybe some do forget about small layouts, but in this and other forums, they are common place so there are considerations that can be discussed to hopefully steer to a good experience.

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Posted by Eilif on Monday, June 15, 2020 12:41 PM

I don't think anyone is in a place to convince railroaders to uniformly reorder the Armstrong curve classification.  Also, I suspect the majority of layouts -especially beginner and casual hobbyist layotus- operate in a limited space and still would find his standards represent their reality.  

For those who have progressed into large personal or club layouts, they dont need to use the Armstrong curve recommendations anyway.  What they need instead is for producers of railroad equipment to simply be simply more forthright about what curve measurements their rolling stock will reliably operate on.   I suspect they don't care much what Armostrong thought a conventional curve was, but they do want to know what curve their latest, super-detailed 89' rolling stock is going to require. 

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Posted by riogrande5761 on Monday, June 15, 2020 12:54 PM

@Elif, as always YMMV.

For those who have progressed into large personal or club layouts, they dont need to use the Armstrong curve recommendations anyway.  What they need instead is for producers of railroad equipment to simply be simply more forthright about what curve measurements their rolling stock will reliably operate on.   I suspect they don't care much what Armostrong thought a conventional curve was, but they do want to know what curve their latest, super-detailed 89' rolling stock is going to require. 

Regarding JA's. curve recommendations, one of the more important things is to read the discussion on rolling stock vs. curves, which is still pretty relevant as cautionary items.  Basically, as you get to sharper curves, you may need to take special consideration with respect to interference of things like underbody details and possible modifications, if necessary.  That is going to be more salient than the labeling of sharp, conventional and broad curve labeling that I'm going to be made very sorry I mentioned even mentioned.  Broken Heart  Anyway, y'll enjoy yourselves doing the 20 lashes with a wet noodle thing.  Clown  

As for forthrightness, that's a discussion you'll need to have with manufacturers.  As I mentioned, Walthers recommends 24 inches for passenger cars but experienced hobbyists have found something larger than that is much better.

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Posted by mlehman on Monday, June 15, 2020 1:12 PM

riogrande5761
As I mentioned to Keven, the question of curve radii boils down to application.

True. However, just focusing on mainline, modern modeling tends to distort the historicasl use of these terms. Yep, everything's bigger, needs broader curves, etc.

But that is essentially reducing the argument to modeling the present or very recent past.

Let's not forget that there are still plenty of people doing narrowgauge. And it's not that everything NG works on 18" radius. It doesn't. But industrial lines do even sharper in the normal course of business. Traction is not so much modeled these days, but also fits in the JA system quite nicely. That's leaving aside those who model the 50s and earlier, where - excepting many passenger cars - lots of stuff was fine with 18" curves.

JA also notes his reduction of curves to 3 broad classes is an attempt to simplify the 14 varieties of curves found in the NMRA Recommended Practices. Since this is an RP, even the NMRA's set of definitions is only a suggestion. In ant case, JA notes that selection needs to be based on a number of factors besides simply measuring and labeling.

Then there's the fact that even modern day lines have certain limits below the allowed minimums, given the life span of many lines. Industrial and branch line traffic is often fine with more restrictive practices, so long as operators know that restrictions are in place and what cars and locos are allowed on certain lines.

How JA defines what works on which of his broad classes of curves snd this info still seems pertinent. JA also supplies examples of these definitions for scales larger and smaller than HO.

Importantly, JA ends his discussion by noting that "Experimentation Ideas an aid to selection of curves" so he's well aware of that defining the changes needed to get certain gear to operate properly is an important part of the process. We can offer all the help in the world online. In the end, it's what happens when the wheel hits the rail is what really counts.

Mike Lehman

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Posted by riogrande5761 on Monday, June 15, 2020 1:16 PM

Aye.

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Posted by Doughless on Monday, June 15, 2020 1:38 PM

Confused.  Is this a continuation of another thread?

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Posted by carl425 on Monday, June 15, 2020 1:52 PM

I'll wager that in Armstrong's time as is the case now, some models will run on 18" curves, some models require 30" curves and most models will run on 24" curves.  This makes 18" for tight, 24" for conventional and 30" for broad as accurate now as it was then.

Keep in mind also that as equipment has gotten longer, models have more often been altered to run on tighter than normal curves.  I'd say it's balanced out.

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Posted by Eilif on Monday, June 15, 2020 2:30 PM

carl425

I'll wager that in Armstrong's time as is the case now, some models will run on 18" curves, some models require 30" curves and most models will run on 24" curves.  This makes 18" for tight, 24" for conventional and 30" for broad as accurate now as it was then.

 

Did a bit of thinking and looking at the Armstrong standards and I think you're absolutely correct.  I assume we look at the standards as denoting reliable running and in that respect I think it's absolutley right.  Sure even bigger curves look better, but for actual operations most will run on 22"/24" and virtually everything will run on 30".    Nothing preventing folks who have the space for going for wider, grander curves, but his numbers still encompass virtually all HO rolling stock and thus are still useful today.
 
I'm only a couple years into the hobby, but is there anything that won't run on a 30" curve?

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Posted by fwright on Monday, June 15, 2020 2:50 PM

What they need instead is for producers of railroad equipment to simply be simply more forthright about what curve measurements their rolling stock will reliably operate on.   I suspect they don't care much what Armostrong thought a conventional curve was, but they do want to know what curve their latest, super-detailed 89' rolling stock is going to require.

Who is volunteering to do the testing?  And what happens if the manufacturer's test track is significantly better in curve joints and lack of kinks than the average Joe's trackwork?  Should the manufacturer degrade the minimum radius because Fred's trackwork is too sloppy to reliably run at the manufacturer's minimum radius?

The club I participate in was trying to establish what the minimum reliable radius for HOn3 operation should be.  Some HOn3 brass locomotives were/are known for being "stiff" and requiring more than 18" radius.  But we couldn't test everything in advance.  So the club settled on eased 24" minimum radius.  Is this enough?  So far, it has been.  But I can imagine there could come a time that a "stiff" K-36 or K-37 or large Shay would struggle with these curves.

Fred W

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Posted by riogrande5761 on Monday, June 15, 2020 3:12 PM

Eilif
Sure even bigger curves look better, but for actual operations most will run on 22"/24" and virtually everything will run on 30".    Nothing preventing folks who have the space for going for wider, grander curves, but his numbers still encompass virtually all HO rolling stock and thus are still useful today.   I'm only a couple years into the hobby, but is there anything that won't run on a 30" curve?

With more and more rolling stock being made to a higher degree of fidelity, some have even reported issues with interference of underbody detail on even a 50' box car!

Here are a few anecdotal experiences I had:

Before BLI came out with their HO CZ passenger cars, I had a set of Kumata (Oriental Ltd/High Country Brass) passenger cars.  One would work on 32 inch curve but another would derail and needed a bit larger radius.

Before the above, Chuck Macklin who is a train book dealer, brought some brass CN&W heavy weight passenger cars over to my garage layout, which had 30 inch minimum curves.  Those cars shorted out on the curve due to the detail on the truck side frames hitting the body of the cars.  

So 30-inches seems generous but I discovered that it's rather tight when it comes to brass some passenger cars.  Of course brass steam engines can have issues on 30-inch curves too or even larger.

Most mass produced plastic rolling stock is manufactured or has compromises to allow operation on 24 inch minimum curves.  Some six axle loco's will operate on 18 inch curves.

But the curve thing reminds me back when I was gaming and remember reading about minimum computer specs recommended.  A lesson I took from that is that you generally don't want to run computer games on the absolute minimum computer specs.  Likewise with model trains, operating them on the minimum recommended by manufacturer may be ok, or as happens with Walthers passenger cars, may be not so much.  I'm going with 32-inch minimums and have a bunch of Walthers passenger cars now and am hoping things will work out well, after all, 32 inches is 8 inches above the minimum 24 recommended.  I have read that changing out the wheels for IMRC wheel sets has made a big difference for those who reported problems with their Walthers passenger car rolling abilities.

Anyway, I realize people have to work with what they got, but in some cases, with a little effort, curves can be increase a bit and result in better experience.  At low radii such as 20 or 24 inches, increasing a couple inches could make a sizable difference in operability, especially if rolling stock is already at the edge of being able to operate at minimum such as 24 inches.

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Posted by selector on Monday, June 15, 2020 3:15 PM

As it evolves, the hobby moves on several fronts.  Brass has effectively been supplanted as the go-to for high details and accuracy, and for realism.  Not entirely, not by quite a long shot in fact, but you still pay about three to five times the price for brass (new). A toy J1 2-10-4 in times of old, IF it were available commercially and not scratch-built in John's day, would decidedly have been seen as a rougher approximation/toy, and not so much as a fine replica in scale the way the Paragon version is.  That model needs 22" minimum, according to BLI, although our hosts and I found through trials that it could creep through 21" curves.  

John's somewhat arbitrary range for the smallest type of curvature still encompasses 22".  I don't know that it should change, or that his category range should change.  If in 2026 nothing runs on curves less than 24", his lower range will be almost meaningless in the context of the day's modeling, so I agree with Fred just above.

John's contribution was to craft a framework for track plan design.  It was a tool set, with rationale provided in his running commentary.  Maybe the word 'dean' is too strong, or hard to appreciate in modern parlance.  Nowadays, the buzzword is 'influencer'.  Whatever the term one uses, he encouraged a lot of nice layouts by making the thinking behind their creation lucid, methodical, and efficient.

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Posted by cuyama on Monday, June 15, 2020 3:19 PM

selector
Maybe the word 'dean' is too strong, or hard to appreciate in modern parlance.

Armstrong innovated or popularized so many things beyond curve radius classifications that we use today – including things like narrow spiral footprints and mushroom benchwork. One or two people not understanding the use of the term "Dean" is not reason enough to scramble for a different word. IMHO, YMMV, etc.

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Posted by riogrande5761 on Monday, June 15, 2020 3:24 PM

selector
John's contribution was to craft a framework for track plan design.  It was a tool set, with rationale provided in his running commentary.  Maybe the word 'dean' is too strong, or hard to appreciate in modern parlance.  Nowadays, the buzzword is 'influencer'.  Whatever the term one uses, he encouraged a lot of nice layouts by making the thinking behind their creation lucid, methodical, and efficient.

For whatever reason, dean of layout design has been coined for years regarding John Armstrong.  As Cuyuma pointed out, we don't need to find a new title because it seems to strong to the newer enlightened among us.  Perhaps history is judging him more harshly as time goes by, and that is often the case as we watch the world around us evolve.

I used to be an avid reader of MR magazine in the 70's, 80's and 90's. and by the mid-1980's I did notice a trend of moderate sized layouts and that was that the standard minimum radius I kept seeing over and over and over was 30 inches.  It was a pattern that repeated and stood out.   But that "trend" that I was seeing seemed to translate in my mind, after enough time and articles, to "conventional" in John Armstrongs nomenclature.  

con·ven·tion·al
/kənˈven(t)SH(ə)n(ə)l/
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adjective
 
  1. based on or in accordance with what is generally done 

So what I saw generally being done in the many MR magazine articles I read concerning moderate and larger layouts, was 30 inch minimums.  In this day and age of increased sensistivities, maybe the smaller layouts feel some how left out when "conventional" curves are not possible in small spaces.  But if it makes some feel better, then call 24 inch radius curves conventional.  It's just a label or term and what is "generally done" may be open to debate.

As noted, a 4x8 layout (another convention based on the standard sheet size of plywood) may be built in a space that can fit a layout a bit larger and 24 inch curves can be accomodated - allowing more variety of rolling stock.  Simply bump up the width from 48 inches to 54 inches (4.5 feet) and heck you could have 24 inch curves.  Whether or not some one feels they want to be conventional or something else, that's anyones call.

But for those who take issue with curve labels, just despense with them and do what you can manage and just keep in mine the limitations associated.

Regardless of these "finer points", Track Planning for Realisitc Operation has a lot of great track planning basics and principles and remains one of my go-to references when I design layouts.

As many are aware, the process of layout design is usually a matter of making compromises based on a list of (here we go) Given's and Druthers!  Kisses

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Posted by cuyama on Monday, June 15, 2020 4:04 PM

riogrande5761
So what I saw generally being done in the many MR magazine articles I read concerning moderate and larger layouts, was 30 inch minimums. 

Statistically, quite a few of the mid-sized layouts I design for others use less than 30" radius in HO (or the equivalent in other scales).

Just for a quick check to see if my clients' requirements were unusual, I looked at the HO layouts that come up in the MR Track Plan Database for sizes 100 sq. ft. to 300 sq. ft. (I think that most would consider that "Mid-Sized" or even large)

I looked at the first 25 that turned up (eliminating Narrow Gauge and purely logging/quarry layouts).

For those 25 layouts, Average (Mean) minimum radius is 24.5". Median minimum radius is 24". Suprisingly, a handful at 18"!

Maybe "Conventional" is, well, still kinda conventional.

Edit: That said, I often recommend 28" with easments in HO for decent performance with most all equipment in a mid-sized space. Broader curves are always preferred when they can work for the concept in the space, of course.

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Posted by ATLANTIC CENTRAL on Monday, June 15, 2020 4:57 PM

I have worn out two copies of "Track planning for realistic operation"...........

And I think JA brought science and planning to layout design in ways never considered as a whole process before him.

On this topic of curves.......and yes I have a nice size space, for my last two layouts and my next one........many decades ago, based on my experiances at the Severna Park Model Railroad Club, I decided any attempt to model a Class I railroad in HO scale required 36" radius curves.

It should be noted here that the Severna Park layout is not all that large, it is only 12' x 36', yet it has 36" minimum mainline curves.

Is it the best track plan in the world? No. Does it work for the goals and space of that group? Yes.

Pictures and a track plan can be found in the June 1973 issue of MR for those having archives access or your own library. 

The exact nature of compromise in this hobby is left up to each modeler, as each has a different set of goals, different space, different skills, different resources, etc.

Can really nice layouts be built with 30" radius? or even 24" radius? Sure.

Many consider my standards extreem, maybe they are. I model 1953, my longest freight car is 75', and there are not very many of them. More on passenger cars later.

My mainline minimum, hidden or visable, is 36" radius. If passenger cars go there, it has 36" or larger curves.

Since the mainline is double track, That means that many curves are 38" or larger.

At one spot there are 5 tracks going around a curve as a yard lead joins the mainline and a double track passenger station lead joins the mainline. So the outer most track is in the neighborhood of 46" radius.

Being an around the room layout with two peninulas, there are only three places where major curves are viewed from the outside.

Passenger cars - I have some 80' passenger cars, they however do not make up most of my passenger car fleet. 

Most of my passenger cars are selectively compressed in the 72' - 75' range, or are models of prototypes that were less than 80' long.

My passenger cars are close coupled with working diaphragms - that touch - all the time. I consider this necessary!

For me, overall visual effect is more important than total accuracy of each car.

Locomotives - even with 36" curves, there are no 2-10-4's on my layout. There are not even any 80" driver 4-8-4's.

I limit steam locomotive rigid driver wheelbases to a scale 21' - the USRA light 2-10-2 is my longest rigid wheelbase steam loco.

All of this is about appearance and reliable operation.

I run long trains, 35-50 cars is really typical, sometimes longer. The main freight yard on the new layout will be 22' long, that's over forty 40' cars.

So my curves are beyond broad.........

I could have packed more layout into my 1500 sq ft if my yard was shorter and my curves tighter - but I don't need or want that, I want to capture a specific "feel" of just how immense railroading is.

Sheldon

    

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Posted by rrinker on Monday, June 15, 2020 6:52 PM

 You have to consider WHEN Armstrong wrote his material. Both the hobby world and the prototype.

 Brass? The floodgates didn't open on that until the early 60's and PFM.

 The prototype was still running mostly shorter cars and shorter locos. Yeah there were giants just retiring, like the Big Boy - but thoose were RARE locos, regardless of how many models of them are made. The everyday loco was the 2-8-0 and 2-8-2. Or 4 axle diesels.

 Modern locos are much larger. Modern rolling stock is bigger - 89 foot stack cars and articulated auto racks, and 60 foot box cars. So you need to up the radius for the classes of curves.

 My 4-8-4's don't look silly on 30" radius curves. The tender can couple to the loco in the closest position. It can handle these curves at warp speed. Most anything I run cn handle #6 turnouts at ridiculous speeds as well, but I am using #8's for mainline crossovers. I am actively considering #5s in the yard, because no big locos or passenger cars will run there, just mostly 40 foot and shorter cars and small switchers. A random 50 foot car here or there. Engine terminal will have #6s, because the biggest locos I have can handle those no problem. The only reason I even drew it out as #6 was because that's the size Peco was going to introduce first in code 70. But it's been over 2 years and all we got so far is the flex track, I'm not holding my breath. If I have to mix rail size then I might as well use the turnout that gets the most out of the space. 

 In the context of the early to mid 50's, Armstrong's classification of curves as sharp, conventional, and broad fits botht he model world and the prototypical world. For MOST modelers. To model lines using some of the true giants of the rails, you may indeed have to adjust those upwards. 

 Space is usually the limiting factor. Few people have hangers. Everything needs to be compressed, including the track. I'd love to just do a single deck, but I can't fit what I want with 30" radius mainline curves. If I expanded that to 36", I wouldn't even get a double track in the part I'm working on now, not with sufficient clearance from the walls and then between the tracks. SO 30" and double deck it will be.

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Posted by BRAKIE on Monday, June 15, 2020 7:39 PM

 My thoughts is if one must use 18" he or she should run small engines like 4 axle diesels or nothing larger then a 2-8-0 and 40 and 50' cars.

Today's highly detailed cars including 72- 89' freight cars and full lenght passenger cars one should try for 30-36" curves even though long cars might still look silly on 30" curves.

As far as that goes and this hit home while designing a new Slate Creek switching layout 63-72' freight cars requires at least a #6 switch or a long Peco to look right. I suppose a size 8 switch might be better?  

Good LDEs and the type of equipment that will be used on the layout should always be considered while designing a layout..

Larry

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Posted by ATLANTIC CENTRAL on Monday, June 15, 2020 7:42 PM

rrinker

 You have to consider WHEN Armstrong wrote his material. Both the hobby world and the prototype.

 Brass? The floodgates didn't open on that until the early 60's and PFM.

 The prototype was still running mostly shorter cars and shorter locos. Yeah there were giants just retiring, like the Big Boy - but thoose were RARE locos, regardless of how many models of them are made. The everyday loco was the 2-8-0 and 2-8-2. Or 4 axle diesels.

 Modern locos are much larger. Modern rolling stock is bigger - 89 foot stack cars and articulated auto racks, and 60 foot box cars. So you need to up the radius for the classes of curves.

 My 4-8-4's don't look silly on 30" radius curves. The tender can couple to the loco in the closest position. It can handle these curves at warp speed. Most anything I run cn handle #6 turnouts at ridiculous speeds as well, but I am using #8's for mainline crossovers. I am actively considering #5s in the yard, because no big locos or passenger cars will run there, just mostly 40 foot and shorter cars and small switchers. A random 50 foot car here or there. Engine terminal will have #6s, because the biggest locos I have can handle those no problem. The only reason I even drew it out as #6 was because that's the size Peco was going to introduce first in code 70. But it's been over 2 years and all we got so far is the flex track, I'm not holding my breath. If I have to mix rail size then I might as well use the turnout that gets the most out of the space. 

 In the context of the early to mid 50's, Armstrong's classification of curves as sharp, conventional, and broad fits botht he model world and the prototypical world. For MOST modelers. To model lines using some of the true giants of the rails, you may indeed have to adjust those upwards. 

 Space is usually the limiting factor. Few people have hangers. Everything needs to be compressed, including the track. I'd love to just do a single deck, but I can't fit what I want with 30" radius mainline curves. If I expanded that to 36", I wouldn't even get a double track in the part I'm working on now, not with sufficient clearance from the walls and then between the tracks. SO 30" and double deck it will be.

                                --Randy

 

Completely agreed.

And I can meet my goals on one level with 36" curves in my 1500 sq ft.

And I don't have a hanger, but I do have virtually all of a nice rancher basement.

I only have share it with a modern boiler, water heater and well tank.

And I have the same 4-8-4 as you, and yes they are fine on 30" curves, and their 70" drivers give them a compact rigid wheel base of only 19.25'.

So they look really good on 36" curves.

Sheldon

    

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Posted by ATLANTIC CENTRAL on Monday, June 15, 2020 8:10 PM

Randy does make a very good point about the era in which JA wrote this book and designed many of his track plans.

The first freight cars longer than 50'-60' were the 1953 introduction of the first 75' piggyback flats. Even by the early 60's, piggybacks and auto racks remained virtually the only long freight cars.

And even the 6 axle diesels of that time were relatively short. An SD7 is 60' long, even E8's are only 70' long.

And these are facts/features that allow the use of tighter curves - OR - give even greater impact to my goals. A string of long modern cars 20 actual feet long might be 20 or 30 cars.

A string of 34' hoppers 20 actual feet long is 50 cars.........

Sheldon

    

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Posted by mlehman on Monday, June 15, 2020 9:22 PM

rrinker
Space is usually the limiting factor. Few people have hangers. Everything needs to be compressed, including the track. I'd love to just do a single deck, but I can't fit what I want with 30" radius mainline curves. If I expanded that to 36", I wouldn't even get a double track in the part I'm working on now,,,

Yes, resources tend to be so finite for one's struggling line, whether mainline or somewhere out in the woods.  In the end, you need to make a choice based on what you want to model and what you want to run. Most folks do OK on the first, but then struggle with the modeled part.

I think JA's classifications were intended broadly while inspiring reflection on how one can best achieve one's goals with the hand you've been dealt.

It's when you start diuscussing how all this applies to sizing up the equipment that is desired to run that things get dicey. Everyone wants an nice direct line from some measurement stated by the mfg to a number they can cite from their layout. People want this to be a simple comparison, slam-dunk and either it works or it doesn't.

Things are rarely that simple if you play near the minimums, folks. You best leave some leeway to be certain of the layout accomodating this and that. If 24" is the bare minimum, then 26" would be better and 28" is what you need to run most 24" stuff without modification. Evene then, a run of passenger cars with lots of detail may have quite a variance in individual car models. What do you do as a mfg? You take the one requiring the widest curves and bump it a couple of inches and *presto!* you're at a comfortable 30" - where most things run OK. It's human nature to prefer to keep your options open. But if you don't really need those broad curves, then things can work quite well also with less real estate.

I wouldn't take a 2" difference in min R too seriously. 4" is more significant. In the end it's about getting specific equipment to work on track you've designed and laid. I run 28" min R on the standard gauge main, mainly because of the recognized issue of Walthers cars having issues at the stated 24" min R. Then came the CZ cars, much the same as it turned out. So good thing I left some slack, and you should, too, in designing a layout. And BTW, no I don't have room for 30" min R.

Some of the folks in the thread here have been around long enough to remember my writeup on getting my CZ cars to run reliably that I wrote up here about that experience with the first run. Yes, not perfect out of the box, but pretty darn good. With a little work, they work great. I sure wouldn't waste much effort at complaining about the min R being imperfect - or to expect a stated min R to be any more than a suggestion it is my responsibility to address.

Mike Lehman

Urbana, IL

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Posted by carl425 on Monday, June 15, 2020 10:26 PM

rrinker
You have to consider WHEN Armstrong wrote his material. Both the hobby world and the prototype.

WHEN Armstrong wrote his material, there were SF and UP 4-8-4's pulling 85' passenger cars on the prototype and even more on model railroads.  I can't think of anything in daily use today that is more demanding on trackwork.

I have the right to remain silent.  By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.

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Posted by selector on Monday, June 15, 2020 10:35 PM

cuyama

 

 

... One or two people not understanding the use of the term "Dean" is not reason enough to scramble for a different word. IMHO, YMMV, etc.

 

Byron, in my world of human conflict studies, words are important and have to have shared meaning.  Words, and constructions of several of them (idioms) fall out of favour over time and take on an 'old fashioned' feel.  Also, as a mediator and negotiator, I have accepted that sometimes part of the negotiation of understanding means finding common terms, often suggested by one or more of the parties trying to find common ground over a topic.  So, while you and I might be comfortable using a term like 'dean', our OP has indicated that he doesn't get it, or why that term and not another that might be more suitable.  While thread posts are intended for everyone to see (if they want to participate in more 'negotiaton over terms and concepts, even facts), my post was intended to elicit a response from the OP in case he feels that another term would be better.  Otherwise, there's simply no discussion, and I don't like taking that approach to a topic if I'm going to play along.  So far, though, nothing from him/her over my thoughts.

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Posted by cuyama on Monday, June 15, 2020 10:48 PM

selector
So, while you and I might be comfortable using a term like 'dean', our OP has indicated that he doesn't get it, or why that term and not another that might be more suitable

No disrespect meant, but I think that the OP understood the word “Dean” perfectly. But because the OP had done no research at all into who John Armstrong was before posting, the OP was questioning the "awarding" of the title, not the definition of it. (Edit: As I understood his post, I could be wrong)

Since our friend Random doesn't yet know who JA was (and hasn't even seen Track Planning for Realistic Operation), it seems unlikely that he would be able to suggest a better title. IMHO, of course.

Edit: And of course, it doesn't matter what we talk about here – I imagine Kalmbach will continue to use the phrase as they like. Wink

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Posted by DAVID FORTNEY on Tuesday, June 16, 2020 1:32 AM

I can only dream of 30" curves. I'm restricted to 24" and maybe a inch or two above that in places. It seems the larger layouts are the only thing talked about today. 

I find that my 6 axle diesels run fine on 24" curves, of course they would look better on larger radius curves. Also just because somebody says that my min should be 30" does not mean I should follow that advice, 24" was my limit and that is it.  If I had 30" I would run longer longer cars , I run 50' cars with a couple of 60' sprinkled in.  You gotta adapt to the space you have and not worry about the space you don't have.

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Posted by BRAKIE on Tuesday, June 16, 2020 8:13 AM

Back in the day 18-22" curves was the norm for most home layouts and Athearn and other brands had short passenger cars to accomondate those curves while Walthers had scale lenght passenger car kits in the 50s as did AHM starting in the 60s.. My Dad's open  operator pit layout had "sweeping" 22" curves. I recall that because he used Walthers full lenght passenger cars.

The first long freight car I can recall was Quality Craft massive 4 truck 96' long whale belly tank car.. There may have been a long wheel based Southern Ry Tobacco barn boxcar but, I not sure. 

I do recall 18" curves started to become unpopular in the mid 60s in favor of 24-30" curves.  In fact I recall 18" curves being called "Trolly car curves" at one of the monthy Division 6 NMRA meet that feature a layout planing clinic.

Like I already mention above,if 18" is the only curve that will fit your  allotted layout space then be sure to use short cars and short wheel based locomotives.

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

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Posted by kasskaboose on Tuesday, June 16, 2020 9:50 AM

There are standards and best practices.  We challenge both with different track radii.  One goal on my current (2nd) layout was running nearly any time of freight car.  That's done!  Nothing much more majestic than seeing a consist of long cars going around a broad curve. 

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Posted by Doughless on Tuesday, June 16, 2020 10:04 AM

Not sure about what Armstrong or NMRA say, its not like it matters who labels what.

For my modern era layout, I consider 30 inch radius curves to be sharp.

- Douglas

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Posted by rrebell on Tuesday, June 16, 2020 10:42 AM

Doughless

Not sure about what Armstrong or NMRA say, its not like it matters who labels what.

For my modern era layout, I consider 30 inch radius curves to be sharp.

 

And in my world 30" is considered a very broad curve, my world is 18" radius but then my longest boxcar is 40' with only a few flat or speciaty cars being any longer (got a bunch of super detailed 36' also.

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