Hi all, my HO layout plan called for an 18" radius mainline with 20.25" r and 22.5" mainlines built out beyond that with flex track, following the 2.25" minimum rule. But then I decided to go with 22" snap track leaving me with no choice but run a 20" r flex track in between if I wanted 3 train operation. I worried about where the three mainlines curved in one spot so I built a test track on a tabletop board and rolled all my longest cars and engines through in every combination. I expected many sideswipes but was shocked to discover that none of my longest passenger cars, Athearn 70 footers, and even my gs64 and gg1 and 2 10 2 Santa Fe and E8s ever touched or got touched by another car. Closest they got was 1/8" inch apart and that's good enough for me. Made my day! -Rob
Lastspikemike That implies that closer track centres would work for parallel tangent tracks....closer to prototype in fact.
That implies that closer track centres would work for parallel tangent tracks....closer to prototype in fact.
I laid my (HO) staging yard with tracks at 1 3/4" on center. The tighter spacing allowed me to get 6 tracks onto an 11 inch shelf. Since only one train comes or goes at a time, there's no sideswipe issues at the entrance. Removing and replacing rolling stock isn't quite as easy, but I use a rerailing ramp for that. No problems with the equipment contacting each other.
Dan
On my old layout, I had 30" inside curves and 32" outside curves. I experimented with my 85' passenger cars (longest cars) and my engine roster. Turns out that the worst offender was my brass NH 2-10-2 on the inside track. The cab overhang would scrape a passenger car going the other way on the outside track. All I had to do was widen the track spacing on the curves by 1/8" and I was all set.
Let's not let the passenger car off the hook, here. It was using up 1/4" of the clearance itself.
Since rolling stock is about 1 1/2" wide, 2" centers leaves 1/2" clearance. Passenger cars hang "inwards" an extra quarter inch on that 32" curve. So if your equipment on the inside curve does the same "outwards", you hit.
Ed
Mister Mikado I built a test track on a tabletop board and rolled all my longest cars and engines through in every combination. I expected many sideswipes but was shocked to discover that none of my longest passenger cars, Athearn 70 footers, and even my gs64 and gg1 and 2 10 2 Santa Fe and E8s ever touched or got touched by another car.
This is great news.
A simple experiment is always the best.
-Kevin
Living the dream.
Mister Mikadomy longest passenger cars, Athearn 70 footers, and even my gs64 and gg1 and 2 10 2 Santa Fe and E8s ever touched or got touched by another car.
What would happen if you had 85' cars?
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
DSchmitt Mister Mikado my longest passenger cars, Athearn 70 footers, and even my gs64 and gg1 and 2 10 2 Santa Fe and E8s ever touched or got touched by another car. What would happen if you had 85' cars?
Mister Mikado my longest passenger cars, Athearn 70 footers, and even my gs64 and gg1 and 2 10 2 Santa Fe and E8s ever touched or got touched by another car.
Two inch centers on 18/20/22 inch curves sounds like a bad idea. I guess the OP got lucky with his rolling stock but it would be interesting to hear how it goes in the future. Especially with passenger cars or other rolling stock not yet tested. Personally I would not choose the danger; even on my 32" + radius curves, I'm generally leaving 2 1/2 inch centers on curves. In my yard, yes, 2 inch centers on the straight sections.
Rio Grande. The Action Road - Focus 1977-1983
Lastspikemike Luck had nothing to do with it. Testing is what worked. Isn't the NMRA recommended minimum spacing something like 2 1/16" anyway?
Luck had nothing to do with it. Testing is what worked.
Isn't the NMRA recommended minimum spacing something like 2 1/16" anyway?
No.
LastspikemikeLuck had nothing to do with it. Testing is what worked.
Mike
For a passenger car, the overhang on the inside of the 22" curve would increase by .17".
Lots of 85' cars won't work on 22", 20" 18".
LION wanted > 24" centers.
Him cut the table with 24" curves so that each track laid would be wider than that.
Him assumed 26", 28", 30" and 32". (Him runs four track main lions.)
Well that didn't work the way I planned: I ended up with sharper curves than watt was intended. Still, with 50' subway cars these curves offer no problems, even with all ten trains running at once.
Yeah... Right... Like I can really get up there these days.
Gotta put an elevator in that building.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
I can verify that with 2 3/8" track spacing a 2-8-8-4 will contact 85' passenger cars on 24" and 26 3/8" curves.
I know this by actual experimentation like Mr. Mikado did.
At my minimum of 36" radius, and given my self imposed restrictions on long rigid steam locos, 2" track centers have always worked fine for me.
Sheldon
As I have contributed a number of times to threads dealing with this matter, I have one item that is 'too wide' and one that is 'too high'. The too high is my Trix GG1 with pantograph extended. The too wide is my Rivarossi H-8 2-6-6-6. In fact, that one loc is also too low in a way (driver's side injector overflow will snag on low shrubs and things lineside, especially along curves).
Used to be the model came with two cabs, one with an extended roof extension that covers the sliding footplate between tender and cab. I damaged mine, so it has the lesser overhang. Good thing because, on curves under about 30", that thing's gonna snag something, a tunnel portal, a passing item of rolling stock, a pole set too close. It's articulated front end helps, but it's still a beefy beast whose front end also cuts a wide swath. So, while others might be fine on reasonably wide curves with a fraction over 2" separation, I need something closer to 2.75".
riogrande5761 Two inch centers on 18/20/22 inch curves sounds like a bad idea. I guess the OP got lucky with his rolling stock but it would be interesting to hear how it goes in the future. Especially with passenger cars or other rolling stock not yet tested. Personally I would not choose the danger; even on my 32" + radius curves, I'm generally leaving 2 1/2 inch centers on curves. In my yard, yes, 2 inch centers on the straight sections.
Thanks for your input, Rio Grande. Those 72 foot Athearn passengers will be my longest, so I'm all set. Anything longer would look even more silly anyway--even the cut-down Athearns' hangover is pushing it. But due to space restrictions I don't have the luxury of prototypical curves so 22" is my max. I might end up with a toy train layout look but since I love just running trains, so be it. -Rob
Mister MikadoI might end up with a toy train layout look but since I love just running trains, so be it. -Rob
It's great that it worked for the small-ish rolling stock he tested.
2" centers are a bad idea for big mainline freight cars and big modern diesels. i routinely have 86' boxcars and 89' flatcars/autoracks, and they like more distance between the tracks for good operation.
Where i slipped and got closer to 2" track spacing they did sideswipe.
John
Water Level Route I had a blast for years running trains on 18" radius curves.
I had a blast for years running trains on 18" radius curves.
Rich
Alton Junction
PRR8259 It's great that it worked for the small-ish rolling stock he tested. 2" centers are a bad idea for big mainline freight cars and big modern diesels. i routinely have 86' boxcars and 89' flatcars/autoracks, and they like more distance between the tracks for good operation. Where i slipped and got closer to 2" track spacing they did sideswipe. John
When it comes to freight rolling stock, I guess "small-ish" depends a lot on what year it is in your imaginary little world? But my curves are big-ish, so it does not effect me. My EM1 will pass 85' passenger cars at 2" centers on 36"/38" concentric curves with no issues.
That loco is the biggest overhang in my fleet.
richhotrain Water Level Route I had a blast for years running trains on 18" radius curves. Mike, is your PM feature working? Rich
Mike, is your PM feature working?
Mike,
Just responded.