Hello All,
For the minimum curves on my pike I use 15-inch Atlas snap track. I also use #2 Peco turnouts.
With this combination I have built a Wye in the center of my 4x8 pike and a corkscrew from the upper level of my coal loading dock back down to the mainline.
The mainline oval of my pike also consists of asymetrical curves consisting of three sections of 18-inch radius and three sections of 15-inch radius curves.
Because of the sharp radius of these curves I only run 4 axle diesel units or an 0-6-0 for my Olde Tyme excursion train.
This setup works well for my purposes.
Hope this helps.
"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"
im n scale and using kato's 28 1/4 as a minimum radius. around the walls on 18 inch shelves. i like big curves, but by using them, i have found alot of the track ends up in the middle so its kind of hard to fit in spur tracks. i think i can manage a few, still tinkering. after seeing a train go around that big curve, even 19 inch radius looks sharp. yet another "trade off" i guess.
The term modest certainly rings a different bell for different people. What is considered to be a huge layout in Japan, is a standard layout in my country, already a big one in the UK, where they build layouts in box files, but certainly a micro layout in the US.
I´d consider my HOm (metre gauge narrow gauge, running on 12mm track)layout of roughly 3 by 5 ft with a minimum radius of 13" to be a modest layout.
Hi all
You call 10' X 18' modest, wow! thats a HUGE ECHO ECho echo space to build a model railroad in.
Most people I know including me dream of having that kind space and think a 9' X 12' room to build nothing but a layout in means they are building a very large layout.
regards John
IRONROOSTERNo this was not a preference thing. I understand that for aesthetic reasons, etc. one could use a large radius. ...They were talking about this as a minimum radius for everybody and how a lot of people buying N scale did not understand they "NEED"ed this radius. Anything smaller wouldn't work.
Paul,
I understand they were misleading this person.
And I noted that this is really NOT helping this person, even though they might have thought they were somehow doing this person a favor.
I just wanted to note that the concept of minimum radius is not simply the sharpest acceptable curve for the quipment being operated. There seems to be some confusion here that min R is some sort of hard number that cannot be violated. It's usually not.
Rather, minimum radius is determined by the choices we make as modelers as much as it is by the physical characteristics of the track and equipment. If that is clearly understood, then people are better able to have a useful discussion of layout design, equipment acquisition, and what's involved in making compromises that still allow us to enjoy the equipment we prefer to operate.
Mike Lehman
Urbana, IL
mlehman IRONROOSTER A few months ago I overheard a hobby shop owner and a customer talking about needing 36" minimum curves in N scale. Which is crazy since one of the advantages of N scale is small curves. Nonetheless, there are reasons why someone migtht choose to go with a relatively generous min R. They have nothing to do with what's "good" or "bad" and I think we're maybe being a bit thin-skinned to say that people who prefer a wider min R are somehow dissing on someone who is constrained in some manner from going wider. In other words, the concept of minimum radius doesn't apply simply to the min R possible with your equipment -- although it's often thought of that way -- but it's also about the aesthetic factors that go with a wider min R. It is regrettable that any experienced member of the hobby or shop owner would discourage anyone from going with a relatively sharp min R because of space limitations provided they take the time to explain the trade-offs that will factor into that decision. A sharp min R is less than desirable in many cases and THIS SHOULD BE POINTED OUT, but that doesn't mean you should get discouraged provided you can adapt what you have in mind to successfully operate a RR that suits you. Big Boys and 15" min R doesn't work, but it would work great with short logging cars and suitable locos, for just a couple of examples. The main issue for anyone's min R is whether or not it works for the operations and equipment that are intended to operate over it. The only time it reflects poorly on one's modeling skills is when you try to push the limits by expecting equipment to run over it that is far too lengthy to work on that sharp of a curve. Then it's not only about staying on the track, but coupler swing, etc.
IRONROOSTER A few months ago I overheard a hobby shop owner and a customer talking about needing 36" minimum curves in N scale. Which is crazy since one of the advantages of N scale is small curves.
Nonetheless, there are reasons why someone migtht choose to go with a relatively generous min R. They have nothing to do with what's "good" or "bad" and I think we're maybe being a bit thin-skinned to say that people who prefer a wider min R are somehow dissing on someone who is constrained in some manner from going wider.
In other words, the concept of minimum radius doesn't apply simply to the min R possible with your equipment -- although it's often thought of that way -- but it's also about the aesthetic factors that go with a wider min R.
It is regrettable that any experienced member of the hobby or shop owner would discourage anyone from going with a relatively sharp min R because of space limitations provided they take the time to explain the trade-offs that will factor into that decision. A sharp min R is less than desirable in many cases and THIS SHOULD BE POINTED OUT, but that doesn't mean you should get discouraged provided you can adapt what you have in mind to successfully operate a RR that suits you. Big Boys and 15" min R doesn't work, but it would work great with short logging cars and suitable locos, for just a couple of examples.
The main issue for anyone's min R is whether or not it works for the operations and equipment that are intended to operate over it. The only time it reflects poorly on one's modeling skills is when you try to push the limits by expecting equipment to run over it that is far too lengthy to work on that sharp of a curve. Then it's not only about staying on the track, but coupler swing, etc.
No this was not a preference thing. I understand that for aesthetic reasons, etc. one could use a large radius. And of course the prototype uses much larger radii than most of us. While one advantage (probably its biggest) of N is a layout in a small space , another is being able to have prototypical curves, 100 car freight trains, etc. in a typical basement. So, sure if you have the space and that meets your objectives then do it.
They were talking about this as a minimum radius for everybody and how a lot of people buying N scale did not understand they "NEED"ed this radius. Anything smaller wouldn't work.
Enjoy
Paul
mlehmanNonetheless, there are reasons why someone migtht choose to go with a relatively generous min R. They have nothing to do with what's "good" or "bad" and I think we're maybe being a bit thin-skinned to say that people who prefer a wider min R are somehow dissing on someone who is constrained in some manner from going wider.
Bingo, well said.
The main issue for anyone's min R is whether or not it works for the operations and equipment that are intended to operate over it. The only time it reflects poorly on one's modeling skills is when you try to push the limits by expecting equipment to run over it that is far too lengthy to work on that sharp of a curve. Then it's not only about staying on the track, but coupler swing, etc.[/quote]
All very true. People can't always go with whats ideal, and of course that may or may not limit things. You do the best you can with what you have. In some cases, you may be able to squeeze a bit wider curves, in some cases no way.
Rio Grande. The Action Road - Focus 1977-1983
IRONROOSTERA few months ago I overheard a hobby shop owner and a customer talking about needing 36" minimum curves in N scale. Which is crazy since one of the advantages of N scale is small curves.
A few months ago I overheard a hobby shop owner and a customer talking about needing 36" minimum curves in N scale. Which is crazy since one of the advantages of N scale is small curves.
While my primary scale is S, I have a test layout that currently includes an HO oval with 15" sectional Atlas curves. My Bachmann 4-4-0 runs around it with no problems pulling 36 and 40 ft cars with body mounted KD couplers.
Sure some trains require 18" or 24", but you go with what you have. Some of that traction stuff gets around tighter curves.
Well let's throw the pidgeon at the cat.
The smallest comercial HO curves avalable are 15" so that is the absalute minimum you can go.
It is restrictive yes but it is the smallest you can go.
I would sugest that the ruling radius on a modest layout is 18" but then my definition of modest may be smaller than the OP's
All our curves are sharp when you concider that what is a 10' radius for us is what the prototype conciders to be very sharp.
I find it disapointing a beginer would be told that the min radius is probably to big to fit in the space his parents or partner depending on age would allow him.
When the the first G&D had close enough to 15 inch curves and when many of us started with a set that had probably 18 inch curves in it.
Some of us have very small layouts and I bet the very small layout people have just as much fun with them as the big layout people do
carl425 I have a memory of a newbie coming into the LHS while I was shopping. He asked a few basic questions about getting started of the guy behind the counter and unsolicited, one of the three "regulars" that always hung out in the shop spoke up about "minimum radius". In just a matter of moments, they had all agreed that they wouldn't even bother with a layout that had less than 30" curves. The newbie left the store without buying as much as a magazine. If you want to be helpful, talk about radius in the context of the trade-offs we have to make when designing a layout to meet our own personal limits and desires. And stay away from dismissive remarks like "trainset track geometry". Otherwise you too will become one of the grumpy old farts hanging out in the LHS scaring off the newbie. BTW, in TPFRO after defining what he considers to be sharp, conventional and broad curves, Armstrong goes on to say that full length passenger cars and modern (85' plus) freight equipment require broad curves to look and operate well. He saw no need to redefine sharp, conventional and broad based on the long equipment - neither do I.
I have a memory of a newbie coming into the LHS while I was shopping. He asked a few basic questions about getting started of the guy behind the counter and unsolicited, one of the three "regulars" that always hung out in the shop spoke up about "minimum radius". In just a matter of moments, they had all agreed that they wouldn't even bother with a layout that had less than 30" curves. The newbie left the store without buying as much as a magazine.
If you want to be helpful, talk about radius in the context of the trade-offs we have to make when designing a layout to meet our own personal limits and desires. And stay away from dismissive remarks like "trainset track geometry". Otherwise you too will become one of the grumpy old farts hanging out in the LHS scaring off the newbie.
BTW, in TPFRO after defining what he considers to be sharp, conventional and broad curves, Armstrong goes on to say that full length passenger cars and modern (85' plus) freight equipment require broad curves to look and operate well. He saw no need to redefine sharp, conventional and broad based on the long equipment - neither do I.
Such a shame to read about this person leaving the store confused and frustrated. These are two traits most experience in trains. They are a lot of fun, but also can create a bit of tension among people who think that a layout must have a certain something to become enjoyable.
I've seen small layouts that were very detailed and looked more enjoyable. That looked more fun than layouts that consumed entire basements without any scenery or logic. How one sets up a layout is certainly a function of time, money, and space. These are the largest factors to consider. Just because someone doesn't have enough of one to have a 30" radius doesn't make their layout any worse that somene with a sizeable operation.
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.
jmbjmb Everytime one of these discussions comes up, sooner or later it begins to seem like a "you're not a real model railroader if ..." with the sum total of those "ifs" being a relatively large layout (larger than the typical spare room in most tract homes).
Everytime one of these discussions comes up, sooner or later it begins to seem like a "you're not a real model railroader if ..." with the sum total of those "ifs" being a relatively large layout (larger than the typical spare room in most tract homes).
Usually it's "your not a real modeler" if you don't build trains from kits and buy RTR - thats the theme thats arisen the most here in the past 3-4 years. This one is new for me but no-bother. There seems to be a few negative vibes in this discussion that I don't know where they come from. If it's a sensitive topic here in MR forums, maybe I'll just avoid it going forward and save those discussions for other venues. Live and learn.
Many/most homes do not have basements. And of those that don't few even have dedicated spare rooms for a layout. I'd love to have a spare room. Maybe once both kids are grown and on their own. Right now I have a shelf along two walls; a total of 26 square feet. Not even as much space as the proverbial sheet of plywood. It has one curve of about 19 inches. While I'd love 30 inch radius, it's just not going to happen.
It depends on what part of the country too. I grew up in California where basements are extremely rare. Later in upstate NY and in Virginia they are quite common, almost standard. Probably half the town houses have them too, but the cost is significantly more - and am appreciative that my wife made it a priority that we could manage after much looking, find a townhouse with a basement - although it's not been without it's problems - water issues.
That said, keep in mind I was in the same boat as many of the readers here. From about 1999 to about 2014, I was living in small apartments with no space for even a 4x8, so I get it, I understand we all can't have the "ideal" features in a layout. In fact I have this "boring donut" layout right now but compared to what I had for the 15+ years prior, I'm pleased realtive to what I used to have - nothing. Before, I was one of those "collectors" dreaming of a time I could build even smallish layout. Maybe when my daughter is out of college and I don't have that Yuge financial burden, I might be able to move into a place with a bigger basement like a few of our veteran members here.
I do have a lot of memories of reading articles with sizable layouts using minimum 30 inch curves, and mentioning it in another topic. That seems to have poked someones bear to the point academic studies were undertaken to prove my memory as somehow faulty - sorry about that. Sure, I realize that space is a very real limitation, but I also see the 4x8 sheet of plywood as a sort of mental standard for design that tends to steer new modelers into 18 and 22 inch modular track dimensions. Of course the 30" or larger dream goal isn't always attainable, but going up even a little above the trainset track geometry can reap rewards. Take it for what it's worth, food for thought, not barbs or perhaps some sort of unrealistic lofty ideals. Cheers and remember, Model Railroading is Fun!
Size is relative when we default to non-linear units. Mine's bigger'n yours is a relative comparison, and it happens also that it is entirely subjective.
Apart from that astounding bit of widsom (..cough...), each of us starts with what 'we got'. For some, it's a shelf above our desk crammed into a corner of a common room. For others, it's 1500 square feet of mostly unimpeded/open basement or out-building. I think it's safe to say most of us willingly expand our lofty fantasies into the available space with alacrity. Every time.
Our visions create our limitations. For me, I wanted broad curves which, for me, meant in the 40" range. The only way I could do that was to have a central operating space surrounded by the benchwork and tracks. And, it happened, with a duckunder access. I got my wishes, but it also meant the track plan was just a folded loop with a rudimentary yard and two long spurs. Big deal. Well, it turns out my lofty fantasy was a longish loop with some decent scenery. I want to run trains, not to operate them. For the best speeds and for trouble-free speed running, broad curves were the way to go.
One caveat...I wanted to run WWII era heavyweights with 4-8-4 engines and larger. It meant that I needed curves wider than what Walthers says is the minimum radius of 24". That set my lower or minimum radius to "Armstrongian tight radius of 24-ish inches (and not his 18). Somewhat later, when I actually towed and shoved strings of those cars, I found my minimum was too low.
As some have stated, we set our parameters using some knowns and some givens, plus a few druthers and dreams. Some of us even use 18" curves on those massive basement empires because that's what it takes to execute the grand plan.
Everytime one of these discussions comes up, sooner or later it begins to seem like a "you're not a real model railroader if ..." with the sum total of those "ifs" being a relatively large layout (larger than the typical spare room in most tract homes). This included a discussion on how the average home size is larger. To be honest, I'm not sure that's completely correct (in that it, like Microsoft support, may be true, but also useless). For several reasons. The size of upper end homes has bloomed greatly which will take the average up, but the size of the typical home may not have followed suit. Also, I've noticed a trend today to count the basement, and sometimes the garage, to get an apparent square footage larger than the same house would have measured 20 years ago.
My point of this is a lot, maybe most, model railroaders have to deal with the constraints thrown at them. Especially new and potential modelers. I would not have become a model railroader if things had been like this 40 years ago. While there was too much nit picking over quality of workmanship, there wasn't the nitpicking over you're layout is too small. The workmanship question has pretty much gone away because so few scratchbuild anymore; everything is RTR. But the size question has not.
jim
carl425 After seeing this quote in another thread and knowing it not to be correct... riogrande5761 every modest home layout in MR magazine since the early 1980's had 30 inch minimum curves, I've always considered anything much less than is getting into the sharp range I decided to do a little homework to see what the MR Trackplan Database could tell me about this. I collected the specified minimum radius on layouts from the 100-300 square feet category (this sounds "modest" to me). I left out narrow gauge layouts, layouts where minimum was not specified, and one 400_ sq.ft. layout that was in the wrong group. Where a mainline and any other radius was specified, I used the mainline number. I ended up with 82 layouts. Of the 82, 60 had a minimum radius less than 30" 22 had a minimum radius of 30" or more The median radius was 24" I think it's interesting that this still matches up with John Armstrong's numbers of 18, 24 and 30 for sharp, conventional and broad. I knew going in that every layout wasn't 30" or greater, but I was a little surprised to see that it was only 27%.
After seeing this quote in another thread and knowing it not to be correct...
riogrande5761 every modest home layout in MR magazine since the early 1980's had 30 inch minimum curves, I've always considered anything much less than is getting into the sharp range
I decided to do a little homework to see what the MR Trackplan Database could tell me about this.
I collected the specified minimum radius on layouts from the 100-300 square feet category (this sounds "modest" to me). I left out narrow gauge layouts, layouts where minimum was not specified, and one 400_ sq.ft. layout that was in the wrong group. Where a mainline and any other radius was specified, I used the mainline number. I ended up with 82 layouts.
Of the 82,
60 had a minimum radius less than 30"
22 had a minimum radius of 30" or more
The median radius was 24"
I think it's interesting that this still matches up with John Armstrong's numbers of 18, 24 and 30 for sharp, conventional and broad.
I knew going in that every layout wasn't 30" or greater, but I was a little surprised to see that it was only 27%.
Thanks for crunching the numbers. My 13x7' layout has a 28" max radius which can easily handle the SD45 loco.
In this case, the type of equipment dictated the curve. The opposite was true when I had a four-axle loco. I like having a broader curve becasue I can run many more consits and had room for an additional two siding tracks. Most important of all was the grudging War Dept. approval.
SouthPennThe largest snap track radius is 24" to fit nicely on a 4'x8' sheet of plywood.
24" radius won't fit on a 4X8, since radius is measured to the center of the curve in scale model railroading and you also need a bit of room for safety at the edge of the benchwork.
4X8 sheets of plywood are the reason most sectional track makers offer a 22" radius in HO. Coincidentally, this makes the monolithic 4X8 not the ideal choice for modeling in HO, but that's another story.
Layout Design GalleryLayout Design Special Interest Group
Water Level Route carl425 Water Level Route Remember too that the mind is good at remembering that which we can relate too. Remembering seeing a curve radius that is at or about what you use is perfectly normal. An interesting observation. Kind of a variation on a theory I heard the other day on the popularity of the cable news networks. "People seek out news coverage that affirms them, not coverage that informs them". It's called confirmation bias. (Wow, I did remember something from those classes!) You must be referring to the Fox News vs. CNN debate. I hear about that one frequently at work.
carl425 Water Level Route Remember too that the mind is good at remembering that which we can relate too. Remembering seeing a curve radius that is at or about what you use is perfectly normal. An interesting observation. Kind of a variation on a theory I heard the other day on the popularity of the cable news networks. "People seek out news coverage that affirms them, not coverage that informs them".
Water Level Route Remember too that the mind is good at remembering that which we can relate too. Remembering seeing a curve radius that is at or about what you use is perfectly normal.
An interesting observation. Kind of a variation on a theory I heard the other day on the popularity of the cable news networks. "People seek out news coverage that affirms them, not coverage that informs them".
It's called confirmation bias. (Wow, I did remember something from those classes!) You must be referring to the Fox News vs. CNN debate. I hear about that one frequently at work.
Let's just let this particular side-issue die here, shall we?
--Steven Otte, Model Railroader senior associate editorsotte@kalmbach.com
Mike
Water Level RouteRemember too that the mind is good at remembering that which we can relate too. Remembering seeing a curve radius that is at or about what you use is perfectly normal.
Remember too that the mind is good at remembering that which we can relate too. Remembering seeing a curve radius that is at or about what you use is perfectly normal. Forgetting those layouts with curve radii that is different from what you use is normal too. The human mind is built to work that way. I can recall many of the layouts featured in MR in the recent past that involved steam, especially in the north-eastern US. Is what I model. Ask me to remember a diesel layout set in the west? Not happening without seeing the article again.
I would postulate that curve radius has been influenced by many things. Like the most popular era to model is the 1950s, it's shorter rolling stock. The largest snap track radius is 24" to fit nicely on a 4'x8' sheet of plywood. The 4'x8' sheet of plywood layouts. (didn't everyone have one?) The decade the layout was built: the plethora of couplers that were available and non interchangeable or compatible; couplers attached to the trucks; large steam engines that had flanges on all drive wheels or not; and the overall quality of the available equipment.
There are too many variables to consider.
I know it's not the Diner, but how about a round of Christmas cheer for everyone!?!
Carl,
Sound slike you have your preferences, too. If min R isn't one, something else often is. There's value in everyone's opinion here, I'm pretty sure.
tomikawaTTRetired statistician speaking. IMHO, compiling statistics on minimum radii on X layouts published in MR over Y years is simply wasted motion. Each of those layout owners had a set of givens and druthers different from all others. Comparing them isn't comparing apples to oranges, it's trying to find meaningful data in fruit salad...My curves suit my prototype rolling stock. The fact that Sheldon's curves are wider is totally irrelevant to me. He has his standards, I have mine. Presumably you have yours. If not, develop them based on rational considerations, not on a meaningless statistical average
Well, BTDT, Chuck.
Sure wish I'd had the option of making the "too wide" mistake.
But I don't think it's a meaningless as you think. A while back, there was a discussion somewhere here on the other side of min R coin, which is the considerable increase in SF of the average US family home. Obviously, everyone doesn't live in an average home or can use it all for the layout...kids, wives, pets all have to share also.
All joking aside, knowing what the average min R is could help folks who've never built a layout and, ahem, feel somewhat inadequate in terms of the space they have available get more comfortable with the space they do have. Sometimes, being happy in life is about adjusting expectations.
Such data, while not really able to give conclusive guidance on what any single individual should do, at least provides the perspective for them to consider as guidance in what reasonable curve min R they should consider.
I'm a big fan of not reading too much into your data, but I think such an exercise would also show the influence of changing life styles, house designs, and prototype changes on layout design. YMMV
Hi Chuck,
tomikawaTTRetired statistician speaking. IMHO, compiling statistics on minimum radii on X layouts published in MR over Y years is simply wasted motion. Each of those layout owners had a set of givens and druthers different from all others. Comparing them isn't comparing apples to oranges, it's trying to find meaningful data in fruit salad.
The intent was never to present any meaningful statistical analysis, just to point out that minimum radius is a choice arrived at by careful consideration of an individual set of givens and druthers and the choice made by most individuals that built publication worthy, spare room sized layouts, was a number less than 30.
The Maryland and Pennsylvania was noted for sharp curves including one that was 20 degrees which is equal to 39 inches in HO. And 54 inches in S scale which I am using.
I am building the first phase of my layout in a 12x31 foot space. Testing has demonstrated that short cars and engines typical of the early 1950's Ma&Pa will run quite nicely on 24" radius curves. But I have been able to increase that to 27 inches (just in case a future acquistion requires a little extra) and still have a central peninsula. I can't run 80 ft passenger cars, but then the Ma&Pa couldn't either. My longest car will be a 56' open platform passenger car.
In my case the sharp curves are in keeping with my prototype.
riogrande5761Carl, why the negative vibes here?
Sorry, I did not mean to insult your layout. I was referring to the boring donut I would have had to build if I had insisted on a 30" minimum radius.
My point is simply that no specific number makes a good or bad radius. It is only good or bad when you take into account the other choices that Byron pointed out.
Merry Christmas to you too. Maybe Santa will bring you one of those WW2 German rail guns to run on your big curves. I'll be looking for a bobber caboose.
Come down to Richmond some time and I'll show you what I'm doing and explain how and why I got there.
Retired statistician speaking. IMHO, compiling statistics on minimum radii on X layouts published in MR over Y years is simply wasted motion. Each of those layout owners had a set of givens and druthers different from all others. Comparing them isn't comparing apples to oranges, it's trying to find meaningful data in fruit salad.
I have a fixed, finite layout space. I have also tested all of my rolling stock for minimum radius capability, individually and coupled into reasonable trains. The result was incorporated into my planning, which calls for minimum 610mm (24 inch) mainline curves. I could just as easily have devised plans with 30, 42, 48, 56.5 or 72 inch minimums, which would have wasted space and made it impossible to include the prototype features I wanted.
I also have a short line with 350mm (14"minus) radius curves, which runs short (or very flexible) cars and locomotives to match. Only one thing forced that on me - I WANTED it that way!
Note that I do not run humongulocos, TTX flats or 89 foot hi-cubes. My curves suit my prototype rolling stock. The fact that Sheldon's curves are wider is totally irrelevant to me. He has his standards, I have mine. Presumably you have yours. If not, develop them based on rational considerations, not on a meaningless statistical average.
Chuck (Lone wolf modeling Central Japan in September, 1964)
Carl, why the negative vibes here? I like 1970's and 1980's rolling stock which includes some long rolling stock. I also think there is merit to pushing the boundaries - it seems like your taking things kind of personally here - sorry if you think my donut layout is boring. Merry Christmas I guess.
riogrande5761everything else was a reasonable minimum that would allow you to run all your equipment smoothly and reliably, which most historically seem to put in the 28 to 32 inch range as a minimum.
Did you read the part of Byron's post about choice and trade-off's?
You need to get over this idea that your preferences need to be everybody else's standards. I for one don't give a damn about auto racks or passenger cars. From the track plan data it looks like MOST others with room sized layouts like you and I have don't care about them either. And these are not average layouts we are talking about. They are layouts good enough to be featured in MR magazine.
I am willing to limit my rolling stock inventory rather than having to settle for a boring donut of a layout. It is a choice for us all to make for ourselves.
cuyama riogrande5761 They came up with a series of formulars on car length vs. curve radii and I found it very thought provoking! That data was actually first posted on the Layout Design SIG's site and is a useful curve radius rule-of-thumb. One of the things that has changed since the original publication of Armstrong's Track Planning for Realistic Operation is that real-life freight equipment and locomotives have grown in length (such as auto carriers). The rule-of-thumb helps estimate curve radius based on equipment length.
riogrande5761 They came up with a series of formulars on car length vs. curve radii and I found it very thought provoking!
That data was actually first posted on the Layout Design SIG's site and is a useful curve radius rule-of-thumb.
One of the things that has changed since the original publication of Armstrong's Track Planning for Realistic Operation is that real-life freight equipment and locomotives have grown in length (such as auto carriers). The rule-of-thumb helps estimate curve radius based on equipment length.
To be fair, 89' foot flat cars and autoracks were being used in the 1960's, and private passenger operations were still going too (85' long) so it seems that John Armstrongs book, which I reverently keep and reference, would have been written at a time when those should have been included for consideration in track planning. Certainly passenger cars, which is why John argued for at least 24 inch curves in a world where many home hobbyists were still thinking 18 and 22-inch curves. Granted, other than scale length passenger cars, long HO train cars such as autoracks and TOFC flat cars were pretty rare in those days. We really didn't start getting lots of 89' freight cars in HO until the Walthers and Schaffer Rails auto racks hit the market, and soon after Accurail 89' flat cars.
I recently completed a fairly large multi-deck custom HO plan for a client that is based in the modern era. Although he would have liked broader curves for appearance’ sake, we maxed out at 32” minimum on the visible layout and 30” in hidden areas. Horizontal easements will help with appearance and operation. We just couldn’t fit anything broader in the space without compromising on his desires for a long mainline run, etc.
Yep yep on easements - I use them too on my 32" curves etc. And yes, of the more recent built large layouts, 30 and 32 inch curves still often end up being the minimums - which certainly should work well for smooth operations as long as some fincky stiff wheeled brass isn't introduced. I had a set of Kumata CIL/OL/HCB brass California Zephyr passenger cars and depending on the car, some would not handle a 32 inch curve, but would do a abit bigger and negotiate it. That last layout I had with those cars I designed with a 33-inch minimum, and was praying I could be ok running them. It was torn down and I sold off the brass CZ cars in favor of the BLI cars, which I now have.
John Armstrong once told a room of layout owners and designers that the only thing worse than a minimum radius that was too small was one that was too large. While he was speaking slightly tongue-in-cheek, I’ve certainly seen cases myself where folks sacrificed too much (IMHO) for a broader minimum radius than they absolutely needed.
I always loved Johns sense of humor. His answer to the broad curve was to include one or two scenic curves with a very broad radius, that you could enjoy long cars on and have them look nice - then everything else was a reasonable minimum that would allow you to run all your equipment smoothly and reliably, which most historically seem to put in the 28 to 32 inch range as a minimum.
John's, point of course, regarding settling for too large a radius is well taken as you need to be able to work with a space and get a track design into it that allows for maximum use and operationability etc. I find that it's not usually a problem it this forum that people are using too big a radius; if anything the universal problem is the opposite, they are trying to shoe-horn trains around as tight a curve as they can manage - usually in the 18 and 22 inch variety, which sure, nock yourselves out.
Very often, people who have room for a layout that can take 18 & 22 inch curves, can sometimes manage to add a little more width to get curves up a little more and open up their ability to operate some longer cars well - even 24 or 26 inch minimums are a major improvement IMO. Think out of the bun, er out of the taco shell, er out of the 4x8 straight jacket! Be free my minions! =P