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Question about dummy unit

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  • Member since
    April 2003
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Posted by Anonymous on Monday, January 24, 2005 8:28 AM
That all makes since. I'll put the rest of the strips back in. Thanks.

Duck
  • Member since
    July 2004
  • 785 posts
Posted by Leon Silverman on Monday, January 24, 2005 8:16 AM
Older trainsets used dummy engines with plastic bodies and frames, along with powerpack/drive trains combinations that made the gradual start-ups we now take for granite impossible.
If you purchased an Athearn Blue Box dummy, you would still get the metal underframe in the engine that would give it enough heft to track well and not get pulled off the track if the train were to jerk start with the dummy on a curve.
Other manufacturers added weight to their engines in order to get traction. If a dummy had a plastic frame, it would still need added weight in order track properly.
Remember the NMRA standard for HO trains - 1ounce plus 1/2 ounce per inch of length. This applies to a dummy engine as well. The dummy engine needs added metal weights if it comes with a all plastic shell and frame.
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Posted by Anonymous on Monday, January 24, 2005 8:05 AM
The added weight is primarly for better tracking. Since there is a lot of pull on it from the rest of the cars behind it there's a lot of pull working on it in the corners so it makes it easier to keep it on track when natural forces want to pull it off the track. The added weight is because there is no extra weight from the engine. The example of what is happening is put a string on a curve on a peice and pull it towards the end. The string wil naturally want to pull into a straight line. Much like what a string of cars would want to do, The added weight also helps when going over turnouts.
Andrew
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Posted by Anonymous on Monday, January 24, 2005 8:01 AM
The metal is to add weight and help tracking qualities - dummy locos and cars that are too lightweight tend to derail more easily, and as a dummy loco will be first in a train after the powered loco, it needs decent ballast so as not to be pulled off the track by the weight of stock behind on curves (this is a problem for real RR's too - hence why they run empty cars near the end of the train). Hope this is of help!
  • Member since
    April 2003
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Question about dummy unit
Posted by Anonymous on Monday, January 24, 2005 7:47 AM
I had a fellow just give me an old train set of his that had been in his attic to a few years. It's an older Life Like set and the engine doesn't work and the rolling stock is not so nice but it's free so I gladly accepted it. I wondered why the dummy engine is so heavy so I took it apart and it's got strips of flat metal stacked inside it from the manu. What would be the purpose/ advantage of this?

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