It is becoming frustrating the occurence of derailments, mainly in my turnouts. I thought I had weeded out the poorer manfactured ones, using only Walthers or Accurails now, replacing couplers, making sure heights are uniform and working properly. And still, if I back a car through a turnout into the frog, (all code 83 Atlas) I may get a derail. Then I may not. All track is code 83, ballasted. I’m using Caboose Industry’s manual throws. Is this a common occurence?
When you checked the coupler height, did you also check the height of the trip pin? If the pin is low, it can snag on parts of the turnout.
Using a Kadee gauge, there is a small flat area below the coupler on the gauge. The trip pin should clear this flat area.
You need to provide more information. Do the same cars de-rail thru all turnouts or just a few? Always the same turnouts? What couplers are you using? You need to eliminate problem areas I would start by checking the coupler height and trip pin height. Could be you have a few low trip pins that snag on the turnouts. Next is to check your wheelsets for correct gauge. Do the trucks pivot freely? There are many causes for derailments. Occasionally I operate on a neighbor’s layout. I can back a 60+ car train thru the whole layout without a derailment.
Depends on what you mean by “common.” A great deal of your success at eliminating derailments can depend on your skill at tuning track and troubleshooting cars. Derailments are common among modelers who haven’t mastered the tuning process.
I’m assuming you mean brands of cars. Newer Walthers cars with machined metal wheels tend to perform well (older ones may benefit from better wheelsets). Accurail cars should also (mostly) be trouble free, but not always with the stock wheels. Accurail’s one-piece plastic wheelsets don’t necessarily work very well. All of my Accurail cars use metal wheelsets. Intermountain and ExactRail wheelsets are of very high quality and work great in Accurail and Walthers trucks.
Cars need to be tuned to allow for proper truck motion. Both trucks should rotate freely, and (contrary to some old school advice that still is repeated everywhere) it’s helpful for both of them to at least allow SOME side-to-side rocking. Many cars out there will derail if one of the trucks is too tight for it to rock at least a little. The old advice about allowing one truck only to rotate worked much better with sprung trucks. One-piece rigid plastic trucks often need to rock for them to track well.
If any of your Accurail cars still have the plastic truck mounting pins, consider replacing those with screws. It’s a lot easier to adjust the trucks with screws.
The brand of car isn’t necessarily a huge deal. Just about any car with trucks, wheelsets, and couplers that are tuned correctly should be fine. Once you get used to it, you should have good luck with other brands besides those you currently use. Standardizing on good wheelsets helps.
Some hobbyists consider Atlas 83 to be of low qua
If Your track work is not up to par it is.
Do You have Your ballast past the spikes and some stuck to the sides of the rail on the inside? Wheel flanges could be hitting those and lifting the wheel. How did everything roll, before ballasting?
Many variables…kinks in track joints before turnout…etc., etc.
Good Luck! More info would help in giving You help…
Take Care! [:D]
Frank
Allow me to ask the basics that can cause derailments.
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Trip pin at correct height checked against the KD coupler gauge?
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Is the cars wheels in gauge? Checked against the NMRA Gauge
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Is the points of the switch smooth? Are the points completely closing?
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Speed…High speed in reverse through a switch can cause derailments.
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Sloppy track work-even the best of us makes mistakes… Any thing laying under the switch points? Is the rail completely in the rail joiners? Even one rail not completely seated in the joiner can cause derailments.
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Truck to tight? Tighten both truck’s screw completely down and back the screw off 2 1/2 turns- a old school lesson that still provides derailment free operation. No need for the cars to wave hello every time they enter a switch.
These other fellers have seen, experienced, and done it all, and so have I. You are not alone, friend. It’s a rite of passage. We all have to learn how to detect problems, find out exactly what their nature is, and then figure out how to rectify them without having to destroy our track system in the process.
The others have listed the most obvious or frequent problems. I have found that a turnout that is twisted, or that is mounded near the frog, or that sags near the frog, can cause derailments. Often it is the approach to the frog that causes the derailment, but AT the frog is where the axle gets displaced. This is true for longer framed locomotives.
I don’t know what you have done to date to try to stem this problem. What I do is get a good strong light behind the item and the location of the problem, and I get good light behind my head shining on the location. I often use an Opti-Visor and get close. Then, with throttle in hand, I slowly run the offending item back and forth, pulling and shoving, and look for that first sign that it is going to go bad. Sometimes all it takes is a few more grains of ballast below the ties there to lift that rail. This happens on superelevated curves where the superelevation isn’t consistent throughout the curve’s apex.
Good luck. Do what yuh gotta do.
So if I read the OP correctly, the derailments are mainly at turnouts - which suggests some take place elsewhere. Also it when backing the cars, he says. He does not mention whether the car is coupled to the locomotive during the problem, or if it happens regardless of where the car is in the train. What the car is coupled to can sometimes be the culprit. And it is interesting that it is cars that derail, not locomotives, again if I read him correctly.
I assume the cars are free rolling, correctly weighted to standards, and there are not details such as “correct” airbrake piping that have been added that might be catching at the trucks, or airbrake hoses that have been added that might be catching at similar hoses on the next car.
The possible problems have been pretty well outlined above by the other posters. (I’d just add that sometimes the turnout is blameless; a friend had constant derailments at a particular turnout but on closer examination he had made an error cutting the flex track leading to that turnout and created a kink, even though the rail ends met just fine. This is very easy to do particularly if you cannot get your head into position to “squint” down the track and see such kinks).
A few trouble-shooting things I do:
If I add a weight to the car temporarily (some guys use bean bags) does it still derail? If not, that does not necessarily mean the car is underweighted (it might of course - or that the weight is skewed or un-centered). Rather it may have to do more with the tracking of the wheel/truck combination.
If I press the car down with my finger (not too much) and run it repeatedly through the turnout, do I feel anything? Grains of ballast that interfere with the flanges can be felt that way. So can issues with the guardrails. You often can also feel wheel wobble even if you cannot easily see it. &n
Hello all,
What scale are you running…
Z, N, HO, HOn3, O, On30, G?
A few thoughts:
- You have given the height of the rails; Code 83, but not the Divergence- -#2, #4, #6 or #8?
- The code of the wheels are important too- -There is a difference between track code and wheel code.
- Is the divergent track going to a straight, crossover or curved section? If going to a crossover or curved section what are is the radius?
- Are the couplers body or truck mounted?
You should not only check proper coupler height and trip pin clearance but also coupler swing; side to side movement.
On my pike I am forced to run 15-inch radius curves and #2 turnouts in some sections. If the couplers do not have enough lateral (side to side) travel, derailments will occur. The couplers are leveraging the trucks off the track because they have reached the lateral limits of their travel.
The solution to limited coupler swing can be to:
- Install longer shanked couplers.
- Trim the sides of the gear box (better done with whisker type couplers) to allow for more lateral movement.
- Not run certain locomotive or rolling stock though tight curves.
Yes, track work can be a problem. If you are sure that your track work is sufficient then I suggest looking at some of the possible problem areas I have outlined.
Hope this helps.
All good points and those can cause issues.
Switches often have gaps in the rails due to electrical concerns. A tremendous number of derailments in and out of switches can be caused in shifting gap alignment. When first constructed, and tests are run on these, they are critically aligned and work great. Over time, due to a number of reasons, expansion, contraction and up, down,left and right shifting can take place. Pay close attention to rail gaps around switches.
I recently had to fight two such instances on my Code 70 switches. They worked great last year, but this spring caused issues derailing locos moving in only one direction through the switches, but not in the other direction.
One switch gap had a rail that had risen almost imperceptively and slightly inside as well. The other had a rather significant displacement to the outside. All is now well with about 30 minutes of work on each. HOn3 flanges are scale and not deep as on some HO models. As such, the trackwork is a bit more critical.
Yes, backing cars through turnouts is a common occurrence in certain instances, namely, new layouts and new modelers. Don’t know if either of these apply in your case.
Backing cars, period, can be a problem, especially around curves and through turnouts. The most likely culprit is faulty track work. Another culprit is the couplers and the trip pins. On passenger cars, the diaphragms can be the culprit. The turnouts can also be suspect, especially the point rails and the height of the frogs.
The problem can be fixed but, first, you need to identify the cause of the problem. Get down at eye level and back up the train slowly and watch where the derailment starts to occur.
Rich
Rob gave all the answers that I would have given especially the use of metal wheelsets and the tightness of the trucks.
One thing I have had a problem with and I found a little harder to detect is vertical variation in the rails. These can cause wheels to ride up or down and begin a derailment. In fact I had one spot that literally a wide vaiety of cars and engines ran through with no problem. When I was test running a new engine it found a slight dip in the rail and would derail there everytime. I shimmed it and it has been great since.
Another thing that I try to do is to make the first inch or so out of the divergent route of my turnouts aligned with the divergent rails before beginning any curve.
Hope this helps.
Mark
Sometimes it can be something odd. I recently had a car start to derail every time it was going through a switch, but only when it was the first car in the train. Drove me nuts.
Turns out that the air hose ( trip pin ) on the car was catching on the air hoses and other items mounted on the front of the engine. I found this by accident. I was using a bright LED flash light to watch the cars trucks as it went through the switch very slowly. I saw the trip pin catch on the engine. Fix? Trim a small amount off the end of the trip pin.
Maybe I should install couplers with longer shanks on the engine.
Also check that the coupler mount box has not turned. This can easily happen when backing up.
There should be zero problems while making a reverse move through a switch or around a curve to accept anything less is foolish and akin to that oft told lie “derailments is part of running our trains”.
Every problem area you mention can and must be fixed if one wishes to obtain 100% trouble free operation and that goal is easily reach…
Why would anybody accept anything less?
Yes,Rich,I’m a stickler for 100% derailment free operation and as I often mention anything less is unacceptable.
ROAR…
Sometimes the wheel is off the rail BEFORE it gets to the turnout. The turnout simply dumps it offf of the tracks so that the problem becomes obvious. Stop the train BEFORE it gets to the turnout, and check all of its wheels. Are they all on the tracks going into the switch? A problem elsewhere can set up a fail at the switch.
ROAR
(LION!)
Larry, from your reply, I am not sure if you are agreeing or disagreeing with me. In any event, let me clarify my response to the OP.
Backing cars through turnouts can be a problem, and often is due to faulty track work, coupler set ups, diaphragms on passenger cars, and the turnout itself, particularly the point rails and elevated frogs. These problems should be corrected to eliminate derailments on back up movements.
While backup derailments through turnouts are common on new layouts and with newer modelers, backup derailments through turnouts need not be inevitable. Using best practices, backup derailments through turnouts never need to occur.
Rich
Rich,I am agreeing with you but,saying to obtain 100% derailment free operation those trouble spots you mention needs fixed.
At the operation inclined clubs I been a member of over the years I have probably switched thousands of cars with no problems only because all freight cars and passenger cars was up to basic standards(wheels in gauge,coupler and trip pin at the correct height) and if a member’s cars could not meet those basic standards they was not allowed to place the cars on the layout until fixed. At one club we operated for months with zero derailments.
Even at the club I’m currently a member of I can run my trains for hours during a open house or the week of the county fair with zero derailments.
Well that’s a lot of explanations and suggestions. Since this is my first attempt at MR in many many years, I’ll chalk it up to a learning curve. Lately I’m leaning towards ripping it up and starting over.
Sometimes the track arrangement may be the culprit, especially when backing. S-curves caused by combinations of curves with turnouts (or turnouts with other turnouts) can lead to derailments. Atlas Snap-Switches are often a challenge in backing because of the sharp diverging path through the frog.