I have 18''R turns on my layout. I am looking to expand my steam collection (HO Scale) with some larger locomotives, but am worried about the consequences of running more drivers on such tight curves. Most locomotives I am looking at have a recomended minimum radius of 22''.
Can any damge be done to the locomotive by running on tight curves?
If you can get a locomotive recommended for 22" curves to operate on 18", I don't believe the locomotive will be damaged as a consequence.
The manufacturer is suggesting that it WON'T operate on 18". As in it will not fit.
Ed
Won't damage the loco, but in all likelyhood loco will derail. You might get lucky with a specific loco but generally larger locos will not run reliably on smaller radius.
One more point - sometimes an engine can run on a low radius, but when you couple cars behind that engine, the overhang derails the coupled cars -- or derails certain cars. The minimum radius that is mentioned in product reviews or advertisements does not always take that into account.
Dave Nelson
Running a locomotive on a too tight curve could result in a derailment. Or depending on the speed it could turn over (if near the edge it could end up on the floor) which might damage some of the detail.
Since 18" is popular in HO, manufacturer's generally try to make their locomotives run on it. When they can't and advertise it at 22", you probably will have problems at 18". Running it very slow might keep it on the track.
Enjoy
Paul
S. Connor I have 18''R turns on my layout. I am looking to expand my steam collection (HO Scale) with some larger locomotives, but am worried about the consequences of running more drivers on such tight curves. Most locomotives I am looking at have a recomended minimum radius of 22''. Can any damge be done to the locomotive by running on tight curves?
Not to worry about damage to locomotive. The issue is derailment. If the maker puts "22 inch radius" right on the packaging, you can be pretty sure the locomotive will derail on 18 inch curves. Maker's go to a lot of trouble to get their product to handle 18 inches, since that is the standard radius in train sets. When engineering fails to squeeze the locomotive around and 18 inch curve, marketing reluctantly allows the "22 inch radius" mark on the packaging to reduce the amount of product returned by customers for derailment.
If the package says "22 inch radius" it is best to believe it.
David Starr www.newsnorthwoods.blogspot.com
Over a long time, I suppose it's possible it could affect the driving wheels negatively. I have a BLI 2-10-4 with 24" recommended min radius. In tests I could get it go around a 22" radius curve, but the wheels squeal pretty bad. I imagine over time that could cause wear and tear on the wheels.
If your layout space only allows for 18"R HO curves, you'd be best to stick with smaller engines - 0-6-0 switcher, geared steam, etc.
A large engine might take the curve, but will look silly doing so. And silly looking trains is not what this hobby is about.
Dave
Just be glad you don't have to press "2" for English.
http://www.youtube.com/watch?v=zQ_ALEdDUB8
http://www.youtube.com/watch?v=6hqFS1GZL4s
http://s73.photobucket.com/user/steemtrayn/media/MovingcoalontheDCM.mp4.html?sort=3&o=27
What will happen?
Hundreds of voices will cry out in 1/87th volume as your train derails and plummets onto the ground.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
I'd be more concerned about damage to the layout, as in when you tear up the tracks to rebuild it.
My concern is that you will spend money on the big steam locomotives and they will end up as shelf queens because you can't run them successfully.
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
I can tell you with confidence that ain't no steamer engineered for a 22" radius that will stay in the rails on an 18" radius curve. No way, no how. Those 4" represent an out-of-spec underage of 18.2%, or about 20% in easy figures.
I can think of the extra friction on the linkages outside the drivers (even assuming the rods don't scrape the flanges), the extra wear on the brass bearings, God-knows-what happening at the wipers, more flange wear (a LOT more flange wear) inside the rail head, and the potential for shorts with metal frame components or cylinders (bad news for decoders potentially). I could even see some scraped-bare painted sections.
A responder already mentioned overhang and coupling problems. Yewbetcha. As an example only related to coupler problems, will you have to drill another hole in the draw bar under the steamer's cab so that the tender trails sufficiently further back to keep its forward bulkhead corners or grabs from snagging on the cab? I'd lay a few coins down for that one.
-Crandell
Another thing to be aware of, is what company is suggesting the minimum radius. For example, the Bachmann Acela Express has a 22" radius as a suggested minimum, but I've managed to run the train around flat 18" curves. I wouldn't recomend it, but I could.
On the flip side, Walthers' passenger cars have a suggested minimum radius of 24", but I've heard that they really need 26" minimum curves to run reliably.
Bowser and Mantua 4-8-4 and 2-8-2 engines used blind center drivers so 18" radius could be run all day. Best bet is to go with the manufactuers recommendation.
Jim
Our prototypes (and this modeler) routinely embargo certain routes to certain rolling stock - for a variety of reasons, substandard curvature being one of them.
The solutions available are:
Why 24 and not 22? Two reasons:
Do I practice what I preach? My mainline has 24 inch radius (and larger) curves, while my shortline wraps itself around curves tighter than 14 inches. At that, all the rolling stock cleared onto the Tomikawa Tani Tetsudo (including a couple of articulated locos and a four truck machinery flat) have been test run down to less than 12 inch radius.
Obviously, my larger locomotives and longer cars are never sent up the hill on rails surveyed by chasing a mountain goat up the valley. They still have lots of roaming room on my visible mainline and in the netherworld of hidden staging yards and thoroughfares.
As for the prototype, if you follow the UP through Wyoming by satellite, you'll see lots of places where curves were widened and wiggles were straightened, changes made possible by modern earthmovers and made necessary by the purchase of Big Boys.
Chuck (Modeling Central Japan in September, 1964)
selector I can tell you with confidence that ain't no steamer engineered for a 22" radius that will stay in the rails on an 18" radius curve.
I can tell you with confidence that ain't no steamer engineered for a 22" radius that will stay in the rails on an 18" radius curve.
You HAD to know this was coming:
I got my Tenshodo GN S-1 4-8-4 to go around 18" radius curves--it was specced for 22". I filed the hole in the drawbar to allow it. But it happened.
Yeah, it looked like an Irish Wolfhound stuck in a dog carrier. REALLY REALLY sad.
And it DID NOT derail while doing it.
Will it ever happen again? No, never.
Soo Line fan Bowser and Mantua 4-8-4 and 2-8-2 engines used blind center drivers so 18" radius could be run all day. Best bet is to go with the manufactuers recommendation.
I remember a review of a model loco where the reviewer complained of the unprotypical blind drivers. Turned out the reviewer was wrong. The prototype had bilnd drivers.
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.
I have two Athearn Genesis SD70ACe. They has a minimum radius of 18", and a recommended radius of 22". I run them on 18" radius curves, but they really overhang ( you can see the outer rail sticking out from under the fuel tank, and one has a habit of tilting cars in the entrances to the corners, or just derailing them. They do run on 18", but for no worries it would be best to go with 22".
Considering the slight problem with the SD70ACe, I wouldn't think about running large steam on 18" radius. Remember, when it comes to the curves on your layout, bigger is always better.
The old 18 inch curves are still here to haunt us, probably due in part to the 4x8 sheet of plywood and what will fit on it - 18 and 22 inch curves.
This comes up time and again, and modelers end up finding out how hamstrung they are by tight modular track curves.
[preach] So even if space is tight, break free of the straight jacket and get curves which are nominally larger, such as 24 inch curves or larger. It only take a little more space and you can run so much more and have a smile on your face. KATO Unitrack in HO offers modular track in a wide variety of cuves so YES, you can do it! You'll be glad you did.
As others have noted, running trains on radii will not damage them, they will more than likely derail so if they fall off the layout, thats the only damage that will occur.[/preach]
Rio Grande. The Action Road - Focus 1977-1983
Curves are like computer specifications. When Microsoft says it will run with 4 GB of RAM, what they did not tell you is that you should have a minimum of 8 GB RAM.
Thus it is with locomotive curves: If they say it will work on 22" radius what they really mean is it would work (and look) much better on 26" or 30" radius curves.
On Route of LION him cut tables with 24" radius edges, the plan being that the curves would *have* to be much bigger, like 26, 28, 30, and 32 for the four track mane lion of him. TRUF IS some of those curves are way to tight for 85' cars but fortunately subway cars of LION are all 50' long and can take any corner I can throw at them.
If you must renovate your layout to accommodate a larger locomotive, you would be wise to go all the way making 24" your minimum and 26 ot 30 your standard. After all, this will not be the only locomotive that you will buy and LION does have som 85' cars that cannot ever run on a 32" radius. That is to say, he has never run them, but they look great parked in the staton.
Computer of LION has 32 GB RAM.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
BroadwayLion Curves are like computer specifications. When Microsoft says it will run with 4 GB of RAM, what they did not tell you is that you should have a minimum of 8 GB RAM. Thus it is with locomotive curves: If they say it will work on 22" radius what they really mean is it would work (and look) much better on 26" or 30" radius curves.
Sound advice which translates into the trainworld. In general, you should expect some disappointment if you are going with recommended minimum radius as well as minimum recommended memory. (btw, Windows 7 64 bit recommended minimum is 2 Gb, I'm running on 4 Gb quite happily - I'm on a tight budget too)
riogrande5761 (btw, Windows 7 64 bit recommended minimum is 2 Gb, I'm running on 4 Gb quite happily - I'm on a tight budget too)
It has come of the functions of Win 8, but retains the start menu and other features required in the work environment.
It looks to be a very good release.
(Nobody knows why there is no Windows 9.)
Depends on what you mean as larger, I run Spectrum Decapods on 18" radius and they look fine and run well. But if you want to run big steam then you will need the larger radius, sometimes much larger. With our limited spaces you need to decide what your prioritys are!
I don't expect to be running any larger than a spetrum 2-10-2. If that doesn't run on 18'' turns, then I will rebuild with 22'' or 24''.
Thanks for all the info, guys! This information has really been a lot of help.
2-10-2 is a pretty long/stiff wheel base for a steamer generally speaking. Either it has some blind drivers or will require bigger radius I would guess, but steam people know way more than me!
I would, if possible, rebuild with the biggest radius you can go with. If you can go up to 24-inches, it will pay dividends in the future. Bigger is always better for curves.
my question is off topic from the op's but i would like to personaly know if my engine will not operate on 18" how will it go through #4 switches should I change to # 6 switches before going father on building?
slow train Ed
I've had good luck running an Athearn 2-8-2 through 18" radius curves. I don't know the minimum recommendation for that loco though. I run a lot of newer 6 axle diesels from Athearn and Intermountain without any problems. Some manufacturers do a good job of stating if long loco or piece of rolling stock I'll work on 18" curves. If they don't list it though, and it's ove 50', my experience has been that you'll likely have problems.
Also, I don't know if Kato makes steam locos, but I've had great results with running their longer rolling stock through 18" Radius curveS. They may look a bit funny, but 58' stack cars and 85' superliners run great, while equivalent cars from other manufacturers do not. Maybe Kato takes extra steps to support smaller layouts?
I have some IHC 2-8-0's and 2-8-2's that handle 18"r track without a problem. However, they may have made some modifications to achieve this.
Good luck,
Richard
I have a BLI 4-6-2 Pacific that runs through 18" curves and Atlas #4's all day long.
Hi. I have an IHC 2-10-4 and it runs on 18" curves. But it won't go through some of my number 4 switches, and it struggles through a small "S" section in my layout. Track also has to be impeccable. Is there a club in your vicinity? I now run my larger steam (8 and 10 drivers) at our local club and have no problems there (it has 24" curves). It gives me another reason to go at the club on a regular basis!
Simon