derailment woes

Discussion in 'FAQs' started by Cactus, Jan 14, 2002.

  1. Cactus

    Cactus Member

    OK sports fans, here's my problem (or at least the top one of many).

    I work in N-scale, but am posting here because it's a technical question (I think).

    I built my layout using PECO turnouts (their MEDIUM #6, code 80), about half insulfrog and half electrofrog. Things went swell until this holiday season, when various family members collectively supplied me with enough cash to buy some rolling stock. So, I'm the proud owner of a half-dozen new Microtrains cars. All should be right with the world…. high quality turnouts and high quality rolling stock.

    But… half of the cars derail on half of the turnouts most of the time. This is not the case for my Atlas cars (their new 55-ton gondolas with their new couplers).

    The situation arises when a train approaches the turnout from it's throat (I don't know the right word, the base of the Y. If the turnout is thrown so that the train continues on the straight path, then there's no problem. But if the turnout is thrown so the train follows the curve of the turnout, then the cars in question derail.

    This is irrespective of track that follows or precedes the turnout, straight or curved, though you might want to know that the tightest curve bordering any turnout is 19" radius. The leading wheel of the car derails within the frog of the turnout, the leading truck doesn't turn far enough to track the curved path. They try to continue the straight path, ride over the lip of the frog and drop down onto the ties past the frog.

    1. the problem is much worse with electrofrog turnouts than insulfrog ones.
    2. the turnouts are brand new, they are not nailed or deformed in any way. I glued them down.
    3. the derailment occurs within the turnout, not at any railjoint or rail that isn't part of the PECO turnout.
    4. the cars are all brand new, not mishandled in any way. They derailed right out of the box.
    5. half of the cars don't ever experience this problem
    6. the trucks on the offending cars appear to work freely when not on the rails; i.e., they don't appear to bind or anything.

    Has anyone encountered something like this? I suppose I'll have to replace the trucks, but I'd like some advice before I go to the expense -- new trucks came on the cars, after all. I bought Microtrains cars and PECO turnouts because I was looking for the best.

  2. billk

    billk Active Member

    My first thought - check the gauge of both the switches and of the wheels.
    Bill K
  3. roryglasgow

    roryglasgow Active Member

    Cactus Bill,

    I've had a similar problem with one engine going over some of my Atlas turnouts. My solution was the bend the tip of the point rail a little bit so that it fit more snugly into the notch in the rail. It may be that the flanges on the MT cars are thinner and are wedging themselves into the space between the point rail and the "straight-away" rail...

  4. Cactus

    Cactus Member

    Billk -- you're right.

    I don't have the proper gauge to measure it, but the offending Microtrains wheels have their flanges set visibly further apart than on those trucks that track dependably through the turnouts. It's as if the axles are a smidge too long.

    This allows the inside wheel (the one that runs through the frog) to swing wide enough to catch the little point in the frog where the final decision is made on which direction to go.

    My older Microtrains cars have axles of the proper length. Half of the new cars have the too-long axles. My Atlas cars all have axles of the correct length. I'm thinking now about replacing the trucks with Atlas trucks.

    Thanks for the idea.
  5. Gary Pfeil

    Gary Pfeil Active Member

    I don't know anything about N scale wheelsets, but would think that you could regauge them, rather than buy new trucks. Press them to proper gauge, secure with a drop of ACC.

  6. Cactus

    Cactus Member


    Can't. They're plastic, all molded as one piece.

    Looks like I'll be operating very carefully for awhile, until more wheelsets appear within the budget.
  7. billk

    billk Active Member

    Get a NMRA wheel/track gauge first. Maybe (doubtful) all you trucks are with spec and it's the turnouts that are wrong!
  8. BDC

    BDC Member

    If you don't mind spending the money, you can buy packs of MT low-profile wheels. They come in packs of 100, maybe smaller ones too. Not sure on the price, but it shouldn't be too bad.
    Nice thing about low-profile is that they have reduced flanges, which would be much less likely to pick at your turnouts. Also, the friction is reduced versus regular wheels. Not that much per truck, but I have seen claims of engines able to haul several more cars with the whole train running on low-profile wheels. Also, with 100 axles, you would be able to select which axles you put on your cars (out-of-gauge vs. properly gauged).
    The downside is $$$. As I said, I don't know how much, but it doesn't cost anything but time to check on the internet. HTH
  9. Gary Pfeil

    Gary Pfeil Active Member

    Bill, After re-reading your post, I suggest you check the measurement of the gap between the stock rail of the diverging route and its guard rail. When a car enters a turnout from the frog end on the diverging route, the guard rail should keep wheels reasonably tight up against the stock rail(the longest wheel base steam loco you want to operate ususally dictates just how close you can get the guard rail to the stockrail). If there is too large a gap, the tendancy would be for the wheels to strike the point of the frog and derail as you describe, since wheels will always butt up against the outside rail of a curve. If the gap is too large, you can install a shim(thin brass or styrene) against the guard rail. The most important thing to do tho is get gauges to check both trackwork and wheelsets. Tho not in N scale, I have understood Microtrains as being quality products, I am surprised to hear they may have such gauge problems. However, turnouts are often a bit sloppy. For sure, having both problems(track and wheelsets) is a sure bet for problems. Hope this helps.

  10. Cactus

    Cactus Member


    The solution was simple. I spent $3.40 for a dozen "wheel sets" from Microtrains. (1 wheel set = 2 wheels on an axle)

    Replaced the wheels on the offending cars and all's well.

    Thanks for the advice!
  11. Woodie

    Woodie Active Member

    given me an idea.....

    hmmm... THat's given me an idea. I bought 4 "wooden" milk vans (el-cheapo) and they just don't run on Garahbara. wobble all over the place and wont even track on straight/flat sections. I'll see if I can reguage them.
  12. Woodie

    Woodie Active Member

    had a look

    Yep..... just had a look. The guage is not quite a flange width wider that other wheelsets. The wheels do slide on the axles, so I'll reguage one and see how it goes. Thanks guys for "putting this idea" into my head. taa. I wondered why they were "reduced" from $21 to $9.99. No I know!
  13. kf4jqd

    kf4jqd Active Member

    Same problem

    I had the same basic problem. I had many causes on my HO layout. Here's what I did. I moved the remote switch out from the track. The cars could get caught on the screws! Next I baght this little device shown in the picture. It messures the couple hieght. The coupler would snag the track. The Ho version is about $3.00 from Wathers. I don't know about N.


    Attached Files:

  14. sumpter250

    sumpter250 multiscale modelbuilder

    NMRA standards gage, don't model railroad with out one.
    No, I am not a mamber of the NMRA.
    If there are any members of the San Diego model railroad club on this forum, you may remember pete from Chicago.
    I'd show up at Balboa Park with power and maybe thirty pieces of rolling stock, and operate all weekend, with very little if any tracking problems. Any time I travel, I like to take along a train to run on a local club layout, and rarely have tracking problems. If there is a secret, it is this; Gauge the wheelsets. Make sure both trucks are loose enought to follow the track. They should freely tilt front to back, side to side. Coupler height should be as exact as you can possibly make it. I find this works in HO standard gauge, and HOn3 also. If cars wobble,,,( I hate wobble ),,, replace the wheelsets, there is usually one wheel that is out of round,or not square with the axle.
  15. Cactus

    Cactus Member

    Problem solved!

    1. I contacted the folks at Microtrains about the problem. They said to put a piece of tape on the guard rail of each turnout, and color it black to match the rail. This works, but is at best a temporary solution. Tape comes off... Adhesive gets on the rails... etc.

    2. I tried heating the guard rail to soften it, then pushing it closer to the main rail. This works, but is risky. If you don't do it just right, you've ruined an expensive turnout.

    3. Atlas just sent me a beta sample of their Microtrains Replacement Wheelsets (#22134). I installed them on my worst-performing Microtrains car, the one that ALWAYS derails on an unmodified turnout. I ran it at 100+ scale mph on every unmodified turnout on my layout. Problem cured!

    Now, I just have to wait until Atlas starts to sell those marvelous wheelsets.
  16. Gary Pfeil

    Gary Pfeil Active Member

    Cactus, If a piece of tape works temporarily, why wouldn't thin sheet styrene work permanently? ACC it in place.

  17. shamus

    shamus Registered Member

    Hi Cactus,
    I would suggest using a small piece of thin styrene and cement it inside the gaurd rail, this will stop the MT's from derailing.

    MT's are the only manufacture to my knowledge that you have to do this with the points in N-scale. Atlas/Lifelike/Minitrix & Arnold all work well.


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