Derailing/Uncoupling Experience (Bachmann) (~2 yrs)

Discussion in 'HO Scale' started by RT_Coker, Dec 24, 2012.

  1. RT_Coker

    RT_Coker TrainBoard Supporter

    (This is not a recommendation for or against Bachmann products!)
    1) Starting with the simple DC layout, no problems.
    2) Adding turnouts to simple DCC layout, random derailing over turnouts.
    3) Fixed one turnout that was causing most of the problems, derailing over turnouts continued.
    4) Tried web, found information that the tips (of the direction changing part of these turnouts) needed to be filed to a sharper edge, no noticeable improvements in derailing.
    a) Lot of work and big loss of confidence in what was coming from web searches.
    5) Investigated problem close-up, no culprits identified.
    6) Decided to just live with it, and keep trains short.
    7) Much later, became aware of (don’t remember how) the knuckle coupler pin clearance.
    a) Cars that derail got inspected, and ones with suspicious pins were bent up so that they could not cause any more derailing.
    b) Derailing over turnout’s problem cleared up!
    8) Decided that longer trains would take precedence over magnetic uncoupling.
    9) Added long trains, random uncoupling.
    10) Eventually realized need for quality couplers of the same type on all cars in a long train.
    a) Uncoupling problems reduced to acceptable level.
    11) Decided to just purchase the higher quality cars, uncoupling problems returned.
    12) Decided that these cars all needed to be check right out of the box, and adjusted if needed.
    a) Bought and used a coupler gage.
    b) Uncoupling problems reduced to acceptable level.
    13) Remaining uncoupling problems occurring over just one turnout of the layout “must be the turnout”.
    a) Rechecked pin clearance on offending cars, all pasted.
    b) Decided to just live with the problem, rather than replace this expense crossover switch.
    c) Sometime later realize what was different about this switch. It was at the bottom of a long downhill grade. I remembered from replacing couplers, that at least some of the cars had a good bit of up/down freedom of movement in the couplers.
    d) Assume downhill pressure on couplers with too much up/down play is the culprit.
    e) Purchase some special washers, and plan on checking and if needed adjust each car.
  2. Flashwave

    Flashwave TrainBoard Member

    Yep, sounds about right. And this would be why I'm changing my Kadee couplers out to Sergent. Up down play is still viable on the small couplker heads, (except on Shelf and Type H couplers), but it cuts the lateral motion out.

    Fun fact: On a straight and level piece fo track, stretch and compress your train by pushing and pulling the last car (caboose) against the engine. You see all that slack in it? all that slack your pulling in and out is the space between the actual coupler knuckles and whatever coupler droop you may be pulling taught. Most couplers are fairly tight laterally in the couplerbox, so the slack is coming out of the joints temselves. I'e seen Kadees manage to bounce themselves undone due soley to this slack action. I've also seen slack action remove Kadee springs from couplers, so you might check on those too the next time you go through and do your insepction. Lost too many trains down a hill into a tunnel because one of the springs decided to ump ship...
  3. RT_Coker

    RT_Coker TrainBoard Supporter

  4. Flashwave

    Flashwave TrainBoard Member

    I don't see much of a difference between spring plastic Mchdnrys, the metal Protomax and other clones, truthfully. And the plastic McHenrys with the wire make great Derail and wheel chock clamps. Just cut the shaft, paint her in asafety white, and "couple" it to the rail. Things won't move...
  5. JNXT 7707

    JNXT 7707 TrainBoard Member

    Been there, done that. if you stay with the hobby long enough, all these issues will come up.
    Switching to a good quality coupler like Kadee will fix a lot of these problems, but as has been noted in other posts - maintaining correct coupler height AND minimizing up/down play are the most important - since even Sergents will fail if not set up correctly. And as you have discovered, trip pins drooping down are notorious for catching on trackwork.
    I have been amazed at the wide range of coupler quality on RTR rolling stock and locos alike, especially with up/down play.
  6. RT_Coker

    RT_Coker TrainBoard Supporter

    For Locomotive Consists or Long Trains

    14) I am now applying a slight downward pressure on a coupler as the unit is moved to the coupler gage to check the coupler pin clearance. This is finding and fixing my remaining derailing problems with locomotive consists and long trains (so far).


Share This Page