More questions

Discussion in 'N / Z Scale Model Trains' started by plbab, Mar 23, 2002.

  1. plbab

    plbab Member

    I have read on some boards about problems with N scale derailment. How does one just starintg out avoid this? Is it caused by bad track laying,engines,or design? Also what are those numbers you see such as 0-8-0 ,0-4-0?
  2. roryglasgow

    roryglasgow Active Member

    Model Railroader ran an article in their February 2002 issue that delt with derailments (in all scales). Here is a synopsis of the main causes that they discuss:

    • Track not in gauge - the rails are either too close or too far apart. This usually isn't a problem with sectional track.
    • Joints between rails not properly aligned.
    • Problems with turnouts - could be a problem with spacing or parts of the mechanism not fitted together properly.
    • Incorrectly installed couplers - height and length need to be correct.
    • Rolling stock might be too light (add weight to it).
    • Normal wear and tear on equipment. The article recommends inspecting everything at least once a year to find problems and fix them. These could include couplers that have gotten out of whack (as opposed to being "in whack"), dirty wheels and so forth.

    My most common cause of derailments is when I forget to switch a turnout and I run a train through it backwards. The engines are usually heavy enough to plow through the points, but the cars hit the back side of the points, then hop up and off the track. ANNOYING! And the worst part is that it happened because of my own stupidity (see the thread in the General section about not being able please everyone). :)

    Other than that, I have very few problems with derailments.

    The numbers you referred to describe the wheel configurations on steam locomotives. It's called the Whyte System, named after the guy who invented it. The first number refers to the number of non-drive wheels on the front of the locomotive. These wheels are called the "pilot" because they help to guide the rest of the machine to keep it on the track. They also support the front weight of the locomotive.

    The last set of numbers are the wheels on the trailing truck. Some locomotives use a trailing truck to support the weight of the cab, firebox, and/or boiler at the rear.

    All of the number inbetween refer to the wheels that provide power (drive wheels). When referring to articulated locomotives, there will be more than one set of drive wheels.

    So, an 0-8-0 has no pilot wheels, eight drive wheels (four axles), and no trailing truck. A 2-6-0 has two pilot (one axle) and six drive wheels. A 4-8-8-4 has four pilot, eight drive, another set of eight drive, and four trailing truck wheels.

    The numbers are sometimes combined with the common name of the locomotive. For example: 2-6-0 Mogul, 2-8-0 Consolidation, 4-8-8-4 Big Boy. The names usually refer to the first customer that ordered such a wheel arrangement. There may be different names for the same wheel arrangement based on who ordered it, though. A 4-8-4 used by one railroad might have different equipment than a 4-8-4 used by another railroad...

    Sorry for the long post. I hope this helps answer your questions!


    P.S. - In parts of Europe, they refer to the number of axles on a locomotive, not the number of wheels. So what we would call a 4-6-2 Pacific over here, they might call a 231 Pacific. Some countries use letters for the drive axles (A = 1, etc.)

    P.P.S. - There is an entirely different system for describing the wheel arrangement of diesel and electric locomotives. It refers to the number of powered and unpowered axles on each truck. Powered axles are denoted with a letter, unpowered with a number. So, a 2-C+C-2 has a leading truck with two unpowered axles, two trucks in the middle with three powered axles each, and a trailing truck with two unpowered axles. Incidentally, that arrangement describes the famous GG1 electric locomotive, which could run "frontways" in either direction.
  3. billk

    billk Active Member

    plbab - A lot, if not all, of the info in the MR article that Rory mentioned is online at
    - Bill

Share This Page