First of all, I’d like to thank everyone who has contributed to my two posts.
The knowledge I have gained is amazing and all the contributions has made it possible to make some needed adjustments, corrections, and a few additions.
With that being said, I have decided to extend my East side arrival, departure, and freight yard for operational purposes. Due to my limited space the East end of my yard is now curved which brings me to my main concern.
Thanks in advance…
MSM
I don't have an absolute answer for you, but I can make some suggestions.
A minimum radius of 36" is great, especially on mainlines, but not really necessary for yards. What is more important on curves is the spacing between tracks, and 2" on center on curves is tight even though you are limiting your rolling stock to 40' and 50' freight cars. Spacing of 2 1/2" on center on curves is far better, at least in my experience.
Years ago, I got some good advice from my LHS guys about spacing of tracks on curves. They recommended that I buy a pair of 85' boxcars and test them on actual track to be sure. I wouldn't blindly rely on the advice of others unless they can say with certainty that 2" on center spacing for 36" radius tracks will work based upon their actual experience.
If this were my layout, I would use 2 1/2" spacing on curves and, since it is the yard, I would step down the radius on curved tracks to something like 32" radius. In fact, that is exactly what I did on my old layout where I installed a yard on a curve on my layout.
Hope this helps.
Rich
Alton Junction
I have a slightly different perspective than Rich.
Large radius curves in a yard can really enhance the prototype appearance, I think:
(pardon the bad white balance on that last photo)
The tightest radius here, the inside track, was 36 inches. Track spacing in the classification yard (the two innermost tracks were the mainline and the A/D track) was 2 inches. 40' cars were the max I had on the layout, but I think up to 55' would have worked fine too. Certainly there would have been no side swiping at that length.
On my behemoth helix on a prior layout, the innermost track was 36" radius, with 2" track spacing. Even 80' passenger cars did not sideswipe on those curves, though they didn't clear by a whole lot.
The biggest operational issue is how well the cars couple on curves in the yard. 50' cars on 36" radius curves should generally couple just fine without a lot of fiddling to align the couplers. If a little bit of fiddling is needed - say between a 35' tank car and a 55' mill gondola (even that shouldn't usually be a problem), well, that's just fine, IMO. Ever see a prototype switch crew have to fiddle with couplers to align them? I have...
Mark P.
Website: http://www.thecbandqinwyoming.comVideos: https://www.youtube.com/user/mabrunton
I'm with Mark, bigger is always better.
On my new layout, the only curves less than 36" radius will be in some industrial areas.
My yard needs to handle every piece of equipment that would be on the mainline.
And with those curves, I have never used track centers wider than 2-1/8". Generally I have found 2" centers work fine for everything once you are above 36" radius.
Sheldon
Since the longest thing the yard will experience is a 65' mill gon, I am sure the 2" spacing is adequate.
Except:
Maybe not if you have to put your fingers between cars. To make sure YOU are happy with the 2" spacing, put down 3 pieces of straight flex track at 2" apart. Litter it with rolling stock. Try fiddling with a flat car or two on the middle track while there's boxcars on the outer two. How fun WAS it?
If it works for you then, 2" is fine. This should apply to both the straight and the curved sections.
Note that the fewer derailments you have, the number of these possibly irritating events lessens. Do good trackwork! Fix your rolling stock! Have fun! Or else!
As far as the curves. Radius is absolutely fine. Keep in mind that the curved sections of track will "never" see coupling or uncoupling. Cuts of cars will be pulled or shoved through. Cuts of cars will occupy. Or not occupy. All of the "action" will take place on the straight sections of yard track.
An exception, of course, is when a cut of cars has its end in the curve. IF you then want to get at it from the other end of the yard, you'll be coupling on a curve. I guess that's why they make bamboo skewers and extra arms and hands. Actually, since you'll want to be aligning both couplers, perhaps a flat stick would work better--you can maybe shove both couplers inwards at once.
I can see there MIGHT be too little straight track in the first yard track from the left. I think I'd just live with it, if that's the case.
Ed
1.5" ? I think not. Trains are 10-11 feet wide, normal prototype clearance minimum is 13'-6" which translates into 1.86" is HO scale, or just under 1-7/8".
2" centers at 24" radius - that is trouble with long cars for sure. You have just been lucking as to brand, truck spacing, coupler setups, etc.
Sheldon,
I think you're in error in your correction to Mike.
If we take the car body width of an AAR standard box car, it is 9' - 10 3/8". If we add 3" on each side for safety appliances, we get 10' - 4 3/8", overall.
That translates into 1.428" width. In HO.
Which is certainly less than 1.5". By a fair bit more than 1/16". A hundreth of an inch, actually.
So you CAN use a 1.5" spacing. Though you CAN'T put your fingers between cars.
But it's been pointed out by Mike that "there's no reason for derailments in yards." So THAT'S not a problem.
You and I, perhaps not being as intellectually adventurous (that's not QUITE the phrase I was after) as Mike, might still go with that 2" that "everyone" likes.
I do confess that I'd like to watch Mike run his 1.5" yard for awhile, preferably with a beverage in hand. Both his and mine.
Totally agree with what you state I have three yards all are spaced 2" to 2 1/4" so I took some track and put them on 1 1/2" center NO way cars would rub I physically tried different cars and most did rub to some extent
I didn't check my curves but I have no problems with them
Mike
LastspikemikeFinally, we've found fitting an Atlas 9" re-railer sectional track into every yard track is a pretty handy place to rail a car for the first time on track. Retailing a derailed car in the yard is easier with one of these to access. These rerailers can be easily disguised as a road crossing. We fit ours all in a row in the yard so the road crossing effect is pretty realistic
You mention this club You have never mentioned the name of it would like to see some pictures of it Is the club on line ?
I know you either can't or don't know how to post your own pictures so maybe the club
7j43k Sheldon, I think you're in error in your correction to Mike. If we take the car body width of an AAR standard box car, it is 9' - 10 3/8". If we add 3" on each side for safety appliances, we get 10' - 4 3/8", overall. That translates into 1.428" width. In HO. Which is certainly less than 1.5". By a fair bit more than 1/16". A hundreth of an inch, actually. So you CAN use a 1.5" spacing. Though you CAN'T put your fingers between cars. But it's been pointed out by Mike that "there's no reason for derailments in yards." So THAT'S not a problem. You and I, perhaps not being as intellectually adventurous as Mike, might still go with that 2" that "everyone" likes. I do confess that I'd like to watch Mike run his 1.5" yard for awhile, preferably with a beverage in hand. Both his and mine. Ed
You and I, perhaps not being as intellectually adventurous as Mike, might still go with that 2" that "everyone" likes.
Again, prototype minimum track centers in present day are actually now 14'.
13' or 13'-6" was the common standard before that.
Current plate diagrams for cars today put 10'-8" as maximum car width over appliances.
That sure is between 10'-11' where I went to school.
Even in the 50's most stuff approached 10' over appliances.
Mike can do whatever he wants, but I'm warning others not to follow his faulty information.
Given the tolerances of NMRA standard wheelsets/gauge/track I would count on cars hitting each other even on straight track spaced at 1.5" centers.
But what could I possibly know after 54 years at this?
On the other hand, I also take exception to the idea of spacing track extra wide unless prototype info show it was done that way at a particular location you are trying to model.
Here in the east especially, land is money and railroads don't waste it.
mikeGTW Lastspikemike Finally, we've found fitting an Atlas 9" re-railer sectional track into every yard track is a pretty handy place to rail a car for the first time on track. Retailing a derailed car in the yard is easier with one of these to access. These rerailers can be easily disguised as a road crossing. We fit ours all in a row in the yard so the road crossing effect is pretty realistic You mention this "we" You have never mentioned the name of "we" would like to see some pictures of "we" Is the "we" on line ? I know you either can't or don't know how to post your own pictures so maybe the "we"
Lastspikemike Finally, we've found fitting an Atlas 9" re-railer sectional track into every yard track is a pretty handy place to rail a car for the first time on track. Retailing a derailed car in the yard is easier with one of these to access. These rerailers can be easily disguised as a road crossing. We fit ours all in a row in the yard so the road crossing effect is pretty realistic
You mention this "we" You have never mentioned the name of "we" would like to see some pictures of "we" Is the "we" on line ?
I know you either can't or don't know how to post your own pictures so maybe the "we"
There. I fixed it. It's a bit clunky, but I got rid of that pesky club reference so that Mike can now respond
Lastspikemike NMRA gauge is 2 3/16" wide.
NMRA gauge is 2 3/16" wide.
I guess you are referring to THE NMRA Standards Gage. It is not 2 3/16" wide. Try again.
If 2" is enough on a curve then 1.5" is enough on a straight.
Right you are! I pointed out that there is a whopping 1/16" to spare, if you run AAR boxcars. If your car is 6 HO inches wider, things start to look really grim.
We use Woodland Scenics underlay which is 1 3/4" wide so our yard tracks are more likely 1 3/4" center to center and we can pick up a car when in the third track between two other cars on tracks.
That's nice, but we're talking about 1.5". So your 1 3/4" is irrelevant. What is your experience picking up cars on yard tracks at 1.5"?
If you are getting derailments on straight tracks you need to relay your track or fix or throw out your locomotive or rolling stock.
Right you are!
I don't worry too much about actual measurements.
I don't doubt that at ALL.
I just lay the track down. I only know that it either works or it doesn't work. If it doesnt work I fix it. It works.
I just lay the track down. I only know that it either works or it doesn't work. If it doesnt work I fix it.
It works.
That's totally marvelous. I know I fix things that don't work, though I do try to do some measuring first. I guess that's just my way, though.
" We" are not a club.
To the OP, I suggest deriving empirical data. You have certain items of rolling stock. They gotta work. Right? So, find out if they'll work down to a certain limit. Get out a sheet of plywood or drywall, fix some track radii..nested to duplicate the conditions in your yard...and run a good sampling of your locomotives and rolling stock around them to see what happens. You'll find an empirical 'lower limit' above which you'll know to craft your curved yard ladders, and you'll construct them with confidence knowing your product will be satisfactory.
This might take you all of 90 minutes, but my guess is it will be much less than an hour. Be organized in your process and sampling, and then run it all using BOTH TRAILING AND SHOVING motions, as happens in a yard.
MSMWith yard spacing proposed 2” on center, using a minimum radius 36” will this be enough clearance to avoid cars from side swiping each other? I’m modeling the 1950’s and most of my rolling stock is limited 40’ and 50’ cars (
Yes, you will be fine. the cars will NOT be side swiping each other. 40 and 50 foot freight train cars will pass each other on a 22 and 24 inch radius with no side swipes. Your broad radius curves make it even better.
Lastspikemike2" on center curves works down to 24" radius for up to 85' passenger cars. No collisions.
This is 100% completely untrue. 85 foot cars will sideswipe each other on 24 and 26 inch radius curves on a 2 inch center.
-Kevin
Living the dream.
"One size doesn't fit all"...........While 2 inch spacing worked for me in the yard, it was tight for the ol "0-5-0" switcher to get to in some cases. On curves, it took a bit of experimenting to get the spacing to safely have the long passenger cars pass each other. IMO, the individual has to figure out what works best for him, and of course looks appropriate too.
I've walked yards in Chicago (C&NW), Louisville (L&N, Durkee Foods), Joliet (ATSF, Durkee Foods, Mobil Oil) and Beaumont (Mobil Oil) and found the separation varied quite a bit - from room enough for an adult to safely walk, to big enough for a small vehicle.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
selector To the OP, I suggest deriving empirical data. You have certain items of rolling stock. They gotta work. Right? So, find out if they'll work down to a certain limit. Get out a sheet of plywood or drywall, fix some track radii..nested to duplicate the conditions in your yard...and run a good sampling of your locomotives and rolling stock around them to see what happens. You'll find an empirical 'lower limit' above which you'll know to craft your curved yard ladders, and you'll construct them with confidence knowing your product will be satisfactory.
richhotrain Years ago, I got some good advice from my LHS guys about spacing of tracks on curves. They recommended that I buy a pair of 85' boxcars and test them on actual track to be sure. I wouldn't blindly rely on the advice of others unless they can say with certainty that 2" on center spacing for 36" radius tracks will work based upon their actual experience. If this were my layout, I would use 2 1/2" spacing on curves and, since it is the yard, I would step down the radius on curved tracks to something like 32" radius. In fact, that is exactly what I did on my old layout where I installed a yard on a curve on my layout.
Mike, somewhere in all this most of us are trying to build a "model" of a railroad. Yes, that is full of compromises.
But looking to the prototype for operational standards is a good place to start.
The NMRA gauge is 2-3/16" wide BECAUSE, it is not a double track clearance gauge, there are pages of information in the NMRA Standard and Recommended Practices on double track spacing.
The NMRA gauge is a bridge and structure clearance gauge, and any simple reasearch will reveal that the prototype uses more generious clearances for trackside structures and bridges than it does for double track minimum spacing.
The pioneers in this hobby many decades ago adopted 2" track centers as a good compromise because it looked acceptably close, provided some extra clearance, and would work at least with larger curves as a single standard.
This allowed manufacturers to make lots of "compatible" products, double track bridges, turnouts, crossovers, tunnel portals, signal bridges and more.
You are obviously welcome to build your layout however you see fit. I personally would want no part of your seat of the pants, hook the flex track together before fastening it, way of doing things.
And I have been doing this successfully for a long time.......
I will stay with my universal 2" track centers, I will keep engineering the path of my trackwork before I install it, and I will likely leave you to it for a while, I have more important things to busy myself with.
And my 100 plus Atlas turnouts work just fine - maybe because they are properly fastened down..........
richhotrainDon't act on the advice of others unless they speak from personal experience
+1
Anyone can read my posts, copy and paste them, and then claim that they are an expert.
Unfortunately, they are using my posts, which are not a good place to start.
There is an NMRA RP (RP-7.2) to provide some guidance on this. The RP assume very large locomotives and 85' rolling stock, so it is probably a bit overconcervative. They recommend around 2.5" spacing for 36" curves.
They do provide a tool to calculate the recommended spacing for your specific rolling stock.
https://www.nmra.org/sites/default/files/standards/sandrp/pdf/curved_track_center_and_obstacle_clearance_assistant_jul_2017.html
Just playing with your rolling stock may be the easier route. However, for someone like me who is still planning and has limited rolling stock, these tools may be more helpful.
LastspikemikeWhatever works for any trackside obstruction has to work for passing trains. That's just geometry. Things either overlap or they don't.
PRR discovered at some point that clearances on Horse Shoe were a bit tighter than the ones used for clearance in the J1 2-10-4 design, with the result that passing engines started trying to knock parts off each other.
There were some yards in the East with so little room between tracks that there would be damage if cars on adjacent tracks had plug doors left open.
It can't matter if only one of the things is moving or both are.
Part of the fun is that the force of contact (and many of the effects) increase greatly with relative speed. At some point there might be aerodynamic effects that could induce deflection or rock.
Overmod
back when I started on RR about 197? worked at Robert Young Yard in elkhart before I got on the GTW anyway some of the tracks off of the hump were off limits to people they were so close together If the cars rocked a bit they would hit I think they finally fixed them long after I was there
And again, tapered wheels and and tapered axle ends do NOT insure that the car is ALWAYS centered on the track...........
Lastspikemike To answer the OP's question indirectly the NMRA recommends wider track centres than 2" for reasons not clear to me. https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7.1_tangent_track_centers_and_clearance_diagrams_2019.01.pdf https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7.2_curved_track_centers_july_2017.pdf https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7.3_curved_track_obstacle_clearances_july_2017.pdf https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7_track_centers_and_obstacle_clearances_july_2017.pdf One wonders why the NMRA gauge is set at 2 3/16" for measuring clearances. The clearances to track centres are 2.5" minimum for a pair of parallel tangent tracks. That's 5/16" wider than the gauge!
To answer the OP's question indirectly the NMRA recommends wider track centres than 2" for reasons not clear to me.
https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7.1_tangent_track_centers_and_clearance_diagrams_2019.01.pdf
https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7.2_curved_track_centers_july_2017.pdf
https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7.3_curved_track_obstacle_clearances_july_2017.pdf
https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-7_track_centers_and_obstacle_clearances_july_2017.pdf
One wonders why the NMRA gauge is set at 2 3/16" for measuring clearances. The clearances to track centres are 2.5" minimum for a pair of parallel tangent tracks. That's 5/16" wider than the gauge!
The NMRA RP actually says tanget (straight) tracks can have a spacing of 1 25/32" for cars of the "classic" era. (which fits the OP 1950s.
The 2.5" spacing is for curved tracks. This is to account for the overhangs in the corner. They are assuming you have a big boy pulling 85' passenger cars so that is probably excessive.
The standards gage is for straight tracks and is actually more for structures. Which have different clearence needs.
There are few things sadder than when you try to help a dog and he tries to bite.
LastspikemikeCentrifugal force would act on trains travelling on both the inside track and the outside track so the only effect of that would be the delta resulting from the differing radii. Pull the other one.
As we say in skeet, PULL!
Good lord, Mike....why not read and think a bit instead of scurrying over to your keyboard at every opportunity.
richhotrain selector To the OP, I suggest deriving empirical data. You have certain items of rolling stock. They gotta work. Right? So, find out if they'll work down to a certain limit. Get out a sheet of plywood or drywall, fix some track radii..nested to duplicate the conditions in your yard...and run a good sampling of your locomotives and rolling stock around them to see what happens. You'll find an empirical 'lower limit' above which you'll know to craft your curved yard ladders, and you'll construct them with confidence knowing your product will be satisfactory. Agreed, and this is why I wrote my earlier response to the OP. richhotrain Years ago, I got some good advice from my LHS guys about spacing of tracks on curves. They recommended that I buy a pair of 85' boxcars and test them on actual track to be sure. I wouldn't blindly rely on the advice of others unless they can say with certainty that 2" on center spacing for 36" radius tracks will work based upon their actual experience. If this were my layout, I would use 2 1/2" spacing on curves and, since it is the yard, I would step down the radius on curved tracks to something like 32" radius. In fact, that is exactly what I did on my old layout where I installed a yard on a curve on my layout. Don't act on the advice of others unless they speak from personal experience. Try it out for yourself by putting down some track and running some cars. You are building a yard on a curve as I did on my layout. Spacing that works on straight mainline tracks is not the same as spacing on a curve, epecially in a yard where you are more likely to need to access individual cars. Rich
Agreed, and this is why I wrote my earlier response to the OP.
Don't act on the advice of others unless they speak from personal experience. Try it out for yourself by putting down some track and running some cars. You are building a yard on a curve as I did on my layout. Spacing that works on straight mainline tracks is not the same as spacing on a curve, epecially in a yard where you are more likely to need to access individual cars.
Lastspikemike Centrifugal force would act on trains travelling on both the inside track and the outside track so the only effect of that would be the delta resulting frim the differing radii. Pull the other one.
Centrifugal force would act on trains travelling on both the inside track and the outside track so the only effect of that would be the delta resulting frim the differing radii. Pull the other one.
Nope. Sorry.
You are wrong. Wronger than Overmod said.
The whole point of bringing up centrifugal force here is that the train tips at a certain angle. If it DIDN'T tip, what's the point?
For trains 1.5" wide, on parallel tracks at 2" centers, when the tipping angle from vertical is 42 degrees, they will touch. I just did an experimental setup to find that number.
You, of course, will say that this is silly, among other reasons because they'd have derailed already. Yes. Quite true.
But:
My POINT is that they WERE 1/2" apart when they were stopped. To get to the above silly point, they have to move closer and closer as they tip further and further. So, although they won't touch for sure until 42 degrees, the possibility that they MIGHT touch increases, too.
Let's see what happens when we close the track centers down to 1.6". Standing still, they don't touch. They're separated by .1" But if they were to tip from centrifugal force, both going at the same speed, that .1" would DISAPPEAR at 21 degrees (experimental result again) from the vertical. And, as pointed out above, the possibility starts increasing at earlier tip angles.
This effect is in addition to the difference of lean angle caused by differing radii.
Overmod, I trust you are getting my point. Note that the trains are traveling at the same speed.
hgodlingThey are assuming you have a big boy pulling 85' passenger cars so that is probably excessive.
My 2-8-8-4 will need to be restricted to the outermost of my hidden return tracks. The cab overhang is so excessive on the outside of the curve that this is necessary.
SeeYou190 My 2-8-8-4 will need to be restricted to the outermost of my hidden return tracks. The cab overhang is so excessive on the outside of the curve that this is necessary. -Kevin
Mmmm. Me like! Good!
(Sorry about letting my inner kid appear--it happens.)
selector You were right on the money, Rich. In a world governed by 'likes', I had merely hoped to offer reinforcement by posting my own version of the same idea.
You were right on the money, Rich. In a world governed by 'likes', I had merely hoped to offer reinforcement by posting my own version of the same idea.