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Rail car placement and derailments

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  • Member since
    February 2008
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Rail car placement and derailments
Posted by kasskaboose on Monday, August 14, 2017 10:58 AM

How to avoid derailments when using different car lengths?  Do you group rail cars based on length or do they operate flawlessly regardless of location in a consist? I don't care how mine align in a consist (except for certain rules with tank cars), but want to continue avoiding the embarrasing derailment when I mix long-short rail cars as I get more of them.  

Some might see this topic similar to linging up kids: certain ones get into trouble when moving together!

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Posted by caldreamer on Monday, August 14, 2017 11:27 AM

There are rules for the placement of cars.  One of the most important is the placement of long cars (80 feet or longer and short cars 45 feet or less).  They must not be placed next to each otehr due to stringlining when the long car pulls the short car off the rails.  Attached is the link to the BNSF System Special Instructions that include the car placement ruls

http://fobnr.org/timetables/bnsf/phase4/SI/SI-15-102807.pdf

  • Member since
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  • From: Bedford, MA, USA
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Posted by MisterBeasley on Monday, August 14, 2017 12:39 PM

My rules are pretty simple.  I limit myself to what works.  My space dictates 18-inch curves, so I run mostly 4-axle diesels and short cars.  Transition Era is gentle on my that way.  I limit my trains to 10 or 12 cars.  I have no severe grades on my layout.

I am also very fussy about trackwork, and I'll put in a lot of effort to identify and fix problems so that I can ignore stuff like "xx car must be run with the A end forward."  I have replaced all my plastic wheels with metal, and taken flaky old trucks out of service.  This gives me more free-rolling cars with fewer issues.  Metal wheelsets lower the center of gravity, also, leading to better performance.  Couplers must pass the gauge test, and Kadees are the standard.

It takes an iron man to play with a toy iron horse. 

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Posted by jjdamnit on Tuesday, August 15, 2017 2:08 PM

Hello all,

On my pike the minimum radius curves are 15-inches with #2 turnouts.

The majority are 18-inch curves with Atlas Snap Switches; #4-1/2's.

The motive power are 4-axle GP's, RS's, F's and switchers.

Most of the rolling stock is 34- to 40-footers.

The exceptions are:

  • 52-foot flatcar in my snowplow consist
  • 52-foot; six-axle depressed center flatcar
  • 81-foot; four-truck depressed center flatcar
  • 48-foot, 60-ton well car. 

All have Kadee couplers body mounted at the correct height.

These cars don't pass through the #2 turnouts, by layout design.

But they will negotiate the 15-inch curves and the Snap Switches- -SLOWLY!!!

These longer flat cars are used in special trains and not part of a manifest consist.

I don't put them in any particular order due to their length or possibility of derailment, they play well with others.

The only problem I encountered was with the four-truck depressed center flatcar.

Because I use between the track Kadee uncoupling magnets, the steel weight in the depressed center section was so close that the the magnets would "Grab" the car.

I replaced the steel weight with lead and it now runs freely over the magnets.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by wp8thsub on Tuesday, August 15, 2017 11:45 PM

In a typical layout situation, just about any car should theoretically stay on the track regardless of what it's coupled to.  Proper tuning of trucks, couplers, and wheelsets is key.  Some models have body bolsters and trucks that interfere with truck motion unless you work on the interface between the two.  In a few cases I've had to swap trucks and/or re-work the car to ensure reliable performance.

Rob Spangler

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Posted by mlehman on Wednesday, August 16, 2017 3:19 AM

While you may want to observe rules for car placement, in practice in HO standard gauge and larger things tend to work OK.

Where I've run into trouble is with narrowgauge. When running empty with some flat cars and most logging cars in HOn3, there is just not enough space to add all the weight needed.

These just track best behind cars weighted heavier. The effect is worst on downgrade curves. Smooth train handling, good maintenance and restricted speeds all help, while the springy 714 couplers lead to some bouncing of the consist that makes things worse.

Mike Lehman

Urbana, IL

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    April 2009
  • From: Staten Island NY
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Posted by joe323 on Wednesday, August 16, 2017 6:17 AM

Almost all derailments on the SIW Are caused by human error not car placement.

Joe Staten Island West 

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    October 2001
  • From: OH
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Posted by BRAKIE on Wednesday, August 16, 2017 7:09 AM

joe323

Almost all derailments on the SIW Are caused by human error not car placement.

 

That holds true for the prototype as well.

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    February 2002
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Posted by wjstix on Wednesday, August 16, 2017 8:08 AM

I would think weight - mixing light and heavy cars - could be as big a problem as car length. Cars that are too light will "stringline" (derail on curves when in a long train) easier than properly weighted cars. I understand real railroads have rules against putting say empty flat cars at the head of a long, heavy freight train for similar reasons.

Stix
  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Wednesday, August 16, 2017 8:22 AM

wjstix
I understand real railroads have rules against putting say empty flat cars at the head of a long, heavy freight train for similar reasons.

As any railfan can tell you that's not always the case.Personally I've seen far more empty centerbeams and bulkhead flats behind the engines then 60-62' flat cars but,I've seen some 62 footers behind the engines..

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    November 2006
  • From: NW Pa Snow-belt.
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Posted by ricktrains4824 on Wednesday, August 16, 2017 8:35 AM

Just so long as the length is not too long for your curves, it "should" (theoretically speaking) not be any issue, so long as there is not any other issues that would cause a derailment, such as bad trucks/wheelsets, coupler issues, weight issues, etc...

However, on our tight curves, a 89' autorack really does not play well with anything extremely shorter (or with short couplers), as there is not enough swing.

But, a 62' center beam, "should" work well with a 40' hopper car, etc....

Ricky W.

HO scale Proto-freelancer.

My Railroad rules:

1: It's my railroad, my rules.

2: It's for having fun and enjoyment.

3: Any objections, consult above rules.

  • Member since
    April 2003
  • From: Clinton, MO, US
  • 4,261 posts
Posted by Medina1128 on Thursday, August 17, 2017 1:22 PM

I built my layout with a minimum of 26" curves. I have no problems with derailments with those. When I did, it was after I installed diaphragms on my passenger cars. I installed longer couplers and that eliminated that problem. The key was to turn them over, then carefully adjust the draft gear so that the diaphragms were barely touching. It was time consuming but well worth it.

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