Trouble with Couplers and Derailing

Obsessed Jun 18, 2020

  1. Obsessed

    Obsessed New Member

    2
    0
    1
    Hello everyone,

    I'm a complete novice with model trains, and I'm running into a problem with our N scale train. My daughter saw an N scale train set at a hobby shop and decided that is what she wanted for Christmas, so I got it for her (It's a Kato Mixed Freight starter set with a UP GEVO locomotive). Runs great.

    I thought it would be nice to get her a slightly tighter track so she can run it on her dresser (she's almost 5, and obsessed with trains...and space). I picked up some Kato Unitrack 8-1/2" Radius track. The Kato Locomotive runs fine and does not derail the cars.

    I recently picked up a FVM GEVO (CSX #5500) and it has a MT coupler of some sort (they don't specify which) but it will rip the front truck off the tracks of whatever first car the locomotive is attached to.

    So, what are my options? I saw that MT sells a "Wide Angle" coupler, but not sure if that would solve my issue. Also don't know if I could swap it for a longer shank MT coupler, but I see there are a dozen varieties it seems so not sure which to get.

    For info, the Kato cars are truck mounted couplers and both locomotives (Kato and FVM) are both body mounted. Not sure if that matters.

    Thanks for any help you can provide!
     
  2. Amtrak505

    Amtrak505 TrainBoard Member

    10
    8
    13
    I've found that if there's a Micro Trains coupler equipped car behind a loco, the trip pin will hit the locos plow and derail the car on certain curves. It sounds like you're running a very tight radius layout, which could also be the issue, but I would recommend either swapping for a longer shank coupler or trimming the trip pin on whatever car you want to be first in consist.
     
  3. John Moore

    John Moore TrainBoard Supporter

    13,396
    12,182
    183
    When using the 8.5 inch rad Kato track 3 axle trucked locomotives will not operate on it well if at all. Then combine that with a body mounted coupler and you will have derailments. My layout uses 8.5 inch rad track and my layout only uses small two axle per truck locos.
     
  4. acptulsa

    acptulsa TrainBoard Member

    3,344
    5,868
    75
    Oh, yeah. That's the whole problem, that and the tight radius. It isn't easy to find locomotives with truck-mounted couplers, as they don't look realistic.

    The purpose of a wide angle coupler is to fix that problem. I don't do N; maybe someone who does can chime in and tell you about how well which works on the Fox Valley unit.

    Other possible solutions: Get one car which isn't too long and has body-mounted couplers, and always couple it to the FV unit. That loco is less likely to tug it off the rails on curves, and it's likely to do that to trucks mounted with couplers.

    Or just run wider curves, preferably with easements. There are creative ways to fix the space problem. I slept on a bunk bed as a kid, for example. The upper bunk had been replaced by a layout.
     
  5. Hardcoaler

    Hardcoaler TrainBoard Member

    10,677
    44,869
    142
    In addition to working the above suggestions, you then might want to find a shorter 4-axle locomotive. These will be better suited to short radius curves, although 8-1/2" is too tight for most modern equipment.
     
  6. NorsemanJack

    NorsemanJack TrainBoard Member

    2,264
    946
    51
    Options are:

    a) forget about running the FVM GEVO
    b) switch to a larger minimum radii curvature
     
  7. John Moore

    John Moore TrainBoard Supporter

    13,396
    12,182
    183
    The 44 and 70 tonner work fine of that radius along with the SW series of locos such as the SW-9 and SW-1500. Surprisingly the Alco RS -1 run fine on it. For steam the small locos with small drivers work well such as the 0-6-0, 2-6-0 and 4-4-0. All are three axle locomotives.
     
  8. Obsessed

    Obsessed New Member

    2
    0
    1
    Thanks for the replies so far, I really appreciate it!

    To clarify, the freight cars are all Kato branded with Kato couplers. The only MT couplers are on the FVM GEVO.

    I guess what throws me for a loop is the fact that the Kato loco, the exact same prototype (both GEVOs) doesn't exhibit the behavior. I'd think I could just swap out a coupler. Everything I have read states that MT couplers do better with this than Kato, which is not what my experience is showing me, hence why I thought maybe I could just try a different MT coupler. From what I can tell (maybe I'm wrong) you cannot go from MT to Kato couplers, only the other way.

    I can try a slightly easier radius I suppose. I just thought if one loco could do it no issue, the other could too.

    I liked the idea of the GEVO, and the CSX #5500 in particular, as it was dedicated to the city of Cincinnati, my hometown. In fact I had to find this guy on Germany's eBay site as I couldn't find it in stock anywhere in the states as it is an older release.
     
  9. acptulsa

    acptulsa TrainBoard Member

    3,344
    5,868
    75
    Oh, no. There are a million ways to imitate something, all different.
    I know you've heard it said, "Don't judge a book by its cover." You ignored that good advice, and look what happened. You went out and bought Kato's evil twin Skippy.

    This site might come in handy if you and your girl stick with the hobby. It will certainly teach you to look at each model differently, no matter how they may resemble each other.

    http://www.spookshow.net/locolist.php?diesels=6&nonbrass=3&sortby=4&Submit=Submit

    Unfortunately both these units do have body-mounted couplers, not frame-mounted. So even if you could figure a way to swap the FV body to the Kato frame, it wouldn't help.
     
  10. CarlH

    CarlH TrainBoard Member

    373
    92
    22
    If you can go to 11 inch radius curves, it will be worlds better.
    Consider that if derailments occur, this is a very frustrating thing to a young person who might be just starting their interest in model trains.

    9.75 inch radius curves will also be noticeably better than 8.5 inch radius curves, but will still be quite limiting for the rolling stock you can run.
     
  11. MK

    MK TrainBoard Member

    3,496
    4,798
    82
    This. You *should* be ok with 9-3/4 radius as all Kato diesels are designed to run that minium. But other 6 axles by other manufactures, as you have discovered, will have a hard time with radius less than that and some even have problems with 9-3/4.

    You can try a "conversion" car that someone suggested. Take this freight car and put a long MT coupler on one end and a regular coupler on the other end and have this freight car always connected to the FVM on the long coupler end. Kato couplers will work with MT couplers. Hopefully the FVM won't pull this conversion car off the tracks on the turns.

    You do have options (c) and (d).

    c) try a conversion car
    d) get shorter 4 axle locos or switchers.
     
  12. CarlH

    CarlH TrainBoard Member

    373
    92
    22
    I think the others who already explained that when you have the body-mounted coupler on a locomotive attached to a truck-mounted coupler on the first freight car which is immediately behind the locomotive, that causes a problem: the body-mounted coupler attached to the loco will want to be close the outside rail of a curve, while the truck mounted coupler on the front end of the first freight car will want to be close to the centerline between the rails. This combination is a derailment just waiting to happen.

    When this combination reaches the point where you have the transition between straight track and curved track, it makes the situation worse. And when the curved track is a tight radius, it gets extremely worse.

    Sometimes I have modified a freight car that originally had body-mounted couplers, so it would have a different truck with a truck-mounted coupler just on one end, so it could serve as an "adapter" car. While using a first car with a body-mounted coupler at its front end to run behind the loco does not totally cure the side-to-side coupler misalignment between the loco and the first car behind it, it does reduce it. And this reduces the chance of a derailment.
     
  13. BigJake

    BigJake TrainBoard Member

    3,259
    6,173
    70
    Your answers to the following three questions may help diagnose the problem, and propose a remedy:

    1. Does the freight car derail only when the locomotive & car transition between straight and curved tracks?
    2. If you built a circle of the 8.5" radius track, and assembled the problem loco/car pair on it (coupled), will it run and not derail?
    3. Does the train with the problem loco run OK on the original radius curves?

    If all the above answers are "yes", you have a problem with too great/abrupt a transition between curvature radius (think of straight track having infinite radius). Real railroads lay easement curves (longer radius curve sections) at the transitions, to avoid more abrupt changes in radius.

    You can create your own easements using sections of larger radius curvature between the straight sections and the rest of the curve. You may be able to put a section of the original radius curve between the straight tracks and the 8.5" radius of the remainder of the curve, creating your own easement between straight and tight curves. Depending on how much room you have, you may try smaller, 15 degree curve sections for your easements. This may also mean that you need 15 degree curve sections of the 8.5" radius, to make up the original, total curve.

    Note that if only question #3 above is answered "no", then you can try experimenting with easement curves of greater radius.
     
  14. acptulsa

    acptulsa TrainBoard Member

    3,344
    5,868
    75
    Of course, this might mean her dresser top isn't wide enough any more. But it might not. Is there much margin between the track and the edge? Even with easements, the tight curves will narrow the circle somewhat.

    Be warned, though. Easements might fix this problem. Then again, they might not.
     
    Last edited: Jun 18, 2020
  15. MK

    MK TrainBoard Member

    3,496
    4,798
    82
    Hey Obsessed, take track with you next time you go furniture shopping for your daughter! :D:ROFLMAO::LOL::cool:
     
    PapaG and TrinityJay like this.
  16. Stephane Savard

    Stephane Savard TrainBoard Member

    639
    1,748
    30
    I own the same Kato set, but in CN colours. My experience is that Kato couplers do not mate well with MT couplers. BUT, they do mate reasonably well with accumate (Atlas) couplers. So when I want to use those Kato freight cars with say, an intermountain loco (MT couplers), i put an Atlas box car between the loco and the Kato cars.

    Of course, I've not tried running on such really tight radiuses.
     
  17. acptulsa

    acptulsa TrainBoard Member

    3,344
    5,868
    75
    Now there's a man who knows how to spark a conversation with strangers!

    Or, consider this: Cut a piece of plywood a few inches bigger than the dresser top. Screw or glue wood strips around the edge of the bottom side of the plywood, so they fit snug enough around the edges of the dresser top to keep the plywood from sliding.

    Now you have a few extra inches for wider curves and/or easements (only about 1.5" out from the support at most, or the edge of the plywood may flex). The wires are now hidden. And you can glue down track, grass, trees, roads, signs, buildings and people.
     
    Last edited: Jun 18, 2020
  18. BigJake

    BigJake TrainBoard Member

    3,259
    6,173
    70
    Or if it's a double dresser, cut it in half, spread them apart so you can put a longer AND wider plywood on top, for more track!

    Who knew that model railroading and interior decorating were so intertwined?
     
  19. acptulsa

    acptulsa TrainBoard Member

    3,344
    5,868
    75
    Nah. The plywood will sag in the middle.

    Cut the dresser and the plywood in half, and get some nice bridges.
     
  20. tehachapifan

    tehachapifan TrainBoard Member

    1,859
    859
    46
    Welcome to the MR version of the 1 foot disease like with boats. "If I add 1 foot here I can have x" radius curves."..."1 foot there and I can add a siding." But, it's a fun illness!;)
     

Share This Page