Is anyone sick of buying a new loco and when you get it in the mail it can’t make it around an 18" radius turn? I just got an Intermountain SD40-2 loco in today and I put it on my test track to program it up and go on around the track and it derails in the turn, wtf. I have bigger six axle locos can run on this track wide open. This is so much BS. I bought a Bowser C630M that did the same thing but I was able to modify it to accommodate 18” turns with no problem. I don’t think I will be able to modify the Intermountain because the front and rear axle are hitting the box housing of the coupler. I will never buy another Intermountain loco ever again. I have an Athearn SD70Ace that can run wide open with no problem. And my Kato SD38-2 no problem and every other loco I own. I have an Athearn GP50 in route I hope I don’t have this problems with this one, I would think if there SD70 would make it with no problem I would think the GP50 would. Peace out.
18" radius turns WT&^%$^&%$&^%$#&
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One of my first railroad books (published 1957 or so) had a chart that showed the class of loco and length of car that would be expected to go around the various radius of curves. I looked at the class of locos and found all the types I wanted. I saw that they were all in the 26" and greater radius. I decided that my railroad would have a minimum radius of 30" (15" in N-Scale). I have evolved through the years to 32" and then 36" and now the plan is that my next railroad minimum radius will be 40".
Obviously, the larger the radius the more options you have, in all respects. The size of the radius though will, more often than not, be dictated by the area that is available to you. My first layout had all 15" radius curves. Did it work? Absolutely, but was very limited to what I could run.
My current layout, even though being constructed from flex track, is based on 18" radius curves. Some of my curves are the equivalent of 18" curves, some closer to 22" curves.
As such, I don't think that 18" radius curves are "bad", they just need to be taken for what they are and engines and rolling stock purchased that will operate on those curves.
Basically, I guess you have to make a decision, do as Iron Horseman did and decide on what trains you want to run then ensure you have the "curves" to accommodate that size train, OR, build a layout with the "largest" size curves the benchwork can accommodate and accept that will determine the size of train you can run.
That would definitely be an asset to have Iron Horseman. Any chance you still have that book and the chart?
I didn't mean to imply that at all Tony, so yes you're misunderstanding me. All I was trying to say was, that if you wanted the trains to look right on the layout while making their rounds, that the curent thinking, (advice was probably the wrong word), is to try to keep the radius of the curves in keeping with the locomotive. The bigger the locomotive, the bigger the radius to LOOK right. Not necessarily operate right. Plus, one thing I would advise is to get away from sectional track when planning or building a layout. Flex track is just that, more flexible when designing and building a layout. Our models can sometimes operate just find by making some changes to the equipment. If you can get a Big Boy, or an AC6000 to operate on 18" radius curves, if it makes you happy, I'm all for it. Remember, Tony, there's no one correct way to Model Railroad.
For Example, I had some friends in Mobile when I lived there, where the ONLY place they had for a layout was in the back of an old busted Ford Commercial Econoline van. They actually lived about 25mile SW of Mobile in a little fishing village called Bayou la Batre. Their max radius on this layout was 15" but they "altered" the six axle units available at the time, mostly Athearn BB's, by removing the middle axle from each unit and pulling the wheels off that axle and replacing the gear back into the trucks. They looked real ridiculous going around those 12" and 15" radius curves, but they were happy with their railroad. They even went as far as to remove all middle axles from cars that had more than 2 axles, and even blinded the 2 middle axles on AHM Y6b's and Big Boys to get them to run as well. The tenders were altered as well, as the Y6b had 6 wheel trucks, and the Big Boy had a centipede tender. On the Y6b, they removed the middle axle from each truck, and on the Big Boy, all wheels except for the end axles on it. They used the longest shanked KD's they could find and just mounted them to the engines and cars with a screw, no draft boxes, no centering springs, and again they had a ball. While they didn't look correct, they did operate correctly.
While the "advice" I posted, which came from a MR article by John Armstrong, was also given with the caveat, "That this actually represents a situation that very few modelers will ever find themselves in. As long as the equipment operates smoothly, if you're happy with it, that's all that counts."
If it came across stronger that it should have, I apologize, I certainly didn't mean to confuse anyone.
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Mike_Arnold
Newbie Modeler
rodney mcgiveron
Member
G'day....Ah...the bain of us all at some stage.....18" radius curves....I have a few Intermountains...all ES44ACs ...strangely...none of them derail much , but my minimum radius would be at a guess , using flex track a bit more than 18"... On my old set track Bachmann EZY track I didn't have much trouble with my couple of intermountains at the time on the 18" curves...if I recall but.........my cheaper Bachmann SD40-2s would come off after a curve on the next turnout quite often...I blamed the turnouts but I think it may well have been the previous curve causing the issue...A good friend had exactly the same problem with Peco track....In the end though I think the biggest issue was a combination of the 18" radius and the overhang on the trucks , with the tighter curve it was just enough to catch the trucks here and there...Although I never completely fixed it ...I used a small file and shaved a tiny bit of plastic off the trucks/pilot underneath which limited the problem somewhat...At the time I didn't have any SD70s so I don't really know how they would have gone...Cheers Rod....
Iron Horseman
Well-Known Member
No. That is one of the first model railroad things I learned (a long time ago) that 18" radius curves are just bad news. It isn't the models its the tiny corners we try to run them around. In fact, I am in the opposite camp. I hate the way Athearn moves the brake cylinder (or completely leaves it off the model), cuts the frame, or the pilot, or on steam locomotives pivots the rear drivers on an articulated locomotive. etc. etc. etc. to make them go around such sharp corners. Other manufactures do similar or make the wheels slop from side to side to allow tight radius running.
One of my first railroad books (published 1957 or so) had a chart that showed the class of loco and length of car that would be expected to go around the various radius of curves. I looked at the class of locos and found all the types I wanted. I saw that they were all in the 26" and greater radius. I decided that my railroad would have a minimum radius of 30" (15" in N-Scale). I have evolved through the years to 32" and then 36" and now the plan is that my next railroad minimum radius will be 40".
wombat457
I'm the one
Obviously, the larger the radius the more options you have, in all respects. The size of the radius though will, more often than not, be dictated by the area that is available to you. My first layout had all 15" radius curves. Did it work? Absolutely, but was very limited to what I could run.
My current layout, even though being constructed from flex track, is based on 18" radius curves. Some of my curves are the equivalent of 18" curves, some closer to 22" curves.
As such, I don't think that 18" radius curves are "bad", they just need to be taken for what they are and engines and rolling stock purchased that will operate on those curves.
Basically, I guess you have to make a decision, do as Iron Horseman did and decide on what trains you want to run then ensure you have the "curves" to accommodate that size train, OR, build a layout with the "largest" size curves the benchwork can accommodate and accept that will determine the size of train you can run.
That would definitely be an asset to have Iron Horseman. Any chance you still have that book and the chart?
Cjcrescent
Master Mechanic
I haven't had a layout with 18" radius curves since my second layout in 1964, (at least I believe that was the year). Even on the shelf layouts I had during parts of my college career had at least 24" radius. The larger the radius of the curve, the less chance for derailments, whether the engine is a 0-4-0, or a 4-8-8-4.
Current advice is that you should run engines "made" for the radius on the layout. Small steamers, or 4 axles diesels for anything with 22" or under. Medium steamers, and "smaller" 6-axles for 22" to 28". 30" to 38" for the larger "midsize" steamers, (4-8-4, 2-8-4's) and any 6 axle diesel, and 38" to anything larger than 48" for all the extra large steamers. Some of these steamers will look a little ridiculous even on 38" so if you can you always go with the largest you can fit, for these behemoths.
Current advice is that you should run engines "made" for the radius on the layout. Small steamers, or 4 axles diesels for anything with 22" or under. Medium steamers, and "smaller" 6-axles for 22" to 28". 30" to 38" for the larger "midsize" steamers, (4-8-4, 2-8-4's) and any 6 axle diesel, and 38" to anything larger than 48" for all the extra large steamers. Some of these steamers will look a little ridiculous even on 38" so if you can you always go with the largest you can fit, for these behemoths.
wombat457
I'm the one
Carey,
I am a little confused now with talk about 28" - 40" radius curves. When I look at, say Atlas, the largest radius curve you can buy is 24". Unless you are using flex track, you are pretty restricted with what can and can't be done.
From what I have fathomed from your post, unless you are using 38" radius curves, you pretty much can't/shouldn't run modern equipment.
Wouldn't what could or couldn't be run be determined, not by the length of the curve but, by the angle of it? Am I not understanding something here?
I am a little confused now with talk about 28" - 40" radius curves. When I look at, say Atlas, the largest radius curve you can buy is 24". Unless you are using flex track, you are pretty restricted with what can and can't be done.
From what I have fathomed from your post, unless you are using 38" radius curves, you pretty much can't/shouldn't run modern equipment.
Wouldn't what could or couldn't be run be determined, not by the length of the curve but, by the angle of it? Am I not understanding something here?
The other track "no-no" to avoid if possible is small # turnouts too close together. At my older club, when coming into the main yard (2 tracks in), being on the wrong one and finding only one particular track available, there a 3 #6's to negotiate, immediately one after another, sort of a double "S". Funny thing is my PA ABBA set (and you know how long those trucks are) negotiate them OK, but the 85' cars behind? Not so good!?
Cjcrescent
Master Mechanic
I didn't mean to imply that at all Tony, so yes you're misunderstanding me. All I was trying to say was, that if you wanted the trains to look right on the layout while making their rounds, that the curent thinking, (advice was probably the wrong word), is to try to keep the radius of the curves in keeping with the locomotive. The bigger the locomotive, the bigger the radius to LOOK right. Not necessarily operate right. Plus, one thing I would advise is to get away from sectional track when planning or building a layout. Flex track is just that, more flexible when designing and building a layout. Our models can sometimes operate just find by making some changes to the equipment. If you can get a Big Boy, or an AC6000 to operate on 18" radius curves, if it makes you happy, I'm all for it. Remember, Tony, there's no one correct way to Model Railroad.
For Example, I had some friends in Mobile when I lived there, where the ONLY place they had for a layout was in the back of an old busted Ford Commercial Econoline van. They actually lived about 25mile SW of Mobile in a little fishing village called Bayou la Batre. Their max radius on this layout was 15" but they "altered" the six axle units available at the time, mostly Athearn BB's, by removing the middle axle from each unit and pulling the wheels off that axle and replacing the gear back into the trucks. They looked real ridiculous going around those 12" and 15" radius curves, but they were happy with their railroad. They even went as far as to remove all middle axles from cars that had more than 2 axles, and even blinded the 2 middle axles on AHM Y6b's and Big Boys to get them to run as well. The tenders were altered as well, as the Y6b had 6 wheel trucks, and the Big Boy had a centipede tender. On the Y6b, they removed the middle axle from each truck, and on the Big Boy, all wheels except for the end axles on it. They used the longest shanked KD's they could find and just mounted them to the engines and cars with a screw, no draft boxes, no centering springs, and again they had a ball. While they didn't look correct, they did operate correctly.
While the "advice" I posted, which came from a MR article by John Armstrong, was also given with the caveat, "That this actually represents a situation that very few modelers will ever find themselves in. As long as the equipment operates smoothly, if you're happy with it, that's all that counts."
If it came across stronger that it should have, I apologize, I certainly didn't mean to confuse anyone.
Last edited by a moderator:
wombat457
I'm the one
No apology needed Carey, was just me confusing myself really. You are absolutely right though when you say a layout should look right, that is where the trade off comes in, in my opinion. I'd love to run modern equipment, SD-70's and so forth, but also realize that it would look out of place on my layout. As it is, I have a couple of loco's that run nicely on the layout but are "probably" too big for it as such.
Luckily, most of my "curves" are concealed so you don't notice too much.
Thanks for the clarification though Carey and as said - no apology needed.
Luckily, most of my "curves" are concealed so you don't notice too much.
Thanks for the clarification though Carey and as said - no apology needed.
Stickymonk
Member
I am limited to my curve radius as my layout is in a 8' x 6' shed, I think the tightest is 18". All but one item of stock will not go round it and that was a scratch built 65' Gondola I made a few years ago, I can still run it but only on part of the track.
Cjcrescent
Master Mechanic
Matthew, I too have found that scratchbuilt rolling stock has a tendency to be the pickiest pieces on a layout. I scratched a 53' flat car once and that thing, due to all the detail on it wouldn't go around a curve smaller than 30". I had built it for a NMRA contest, and one of the judges wanted it after the contest was over. Even after I explained to him that it couldn't take anything smaller than 30" radius, he still wanted it. So I said, make me an offer. He did and I did, and now that car is rolling around some big SP layout out west somewhere.
All is well fellows I got the Intermountain SD 40 to work on the test oval. I am using Pecos flex and it must be close to 18" radius turns. I guess my complaint is when I ordered it non of the adds, Model Train Stuff, Train World etc, don't give you minimum radius turns, it sucks that you have to modify your equipment when you get it. I was looking in the manual that came with the loco and it does state 22" minimum radius. If the ad would have said a minimum radius I might have had second thoughts about ordering it. No biggie I was able to make it work but the poor fellow who can't modify his stuff is "stuck like chuck". I guess with that tight of turn like you guys are saying you are limited to what you can run on that size turn. I guess I was venting a little prematurely thanks for the input guys. Peace.
I am surprised that non of the guys that are anal about prototype modeling arn't jumping on this thread and saying that that thing shouldn't be running on that turn it doesn't look right. I am a racer from way back and I am more performance directed instead of prototypical I guess. "All show & no go" wasn't my thing.
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