How much "compression" is normal?

Pastor John Apr 6, 2020

  1. Pastor John

    Pastor John TrainBoard Member

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    I've been thinking about the possibility of building a model of a local Intermodal yard. I found the Google satellite view a while back and today was using it to measure the actual size of yard. The yard itself is about 3,000 feet long while the entire yard, including it's approach sidings, is about 1.12 miles. At 1:87 scale that still 34 feet of yard and a total of 67 feet with the sidings.

    Yikes!

    Obviously, there's no practical way to build that at scale so some compression is obviously necessary.

    But what amount of compression is "normal" when you're trying to model things like that?
     
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  2. Point353

    Point353 TrainBoard Member

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    Here's an example of a compact representation of an intermodal facility:

    [​IMG]
     
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  3. acptulsa

    acptulsa TrainBoard Member

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    8:1. If you have a 9:1 compression, you have to buy high octane gas.

    Seriously, how do we quantify that? The only answer I can think of is, enough to make it fit your space.
     
  4. Chops

    Chops TrainBoard Member

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    Nice example above. Not too deep, nice clean turnouts that correspond nicely with stubs.

    The main limiting factor is to not get too happy with laying in tight crossovers, #4 turn outs, facing turnouts without spacing, most importantly if you are using 86' and above cars. Speaking for myself only, my general rule of thumb is KISS. I get ahead of things, and I spend
    more time replacing, adjusting, rerailing, re-everything, than I do running trains. Also, since you ask, never place anything that you need to get at further than 24 inches away from any given contralateral spot. If you can't reach it, you will regret it.
     
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  5. Chops

    Chops TrainBoard Member

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    too
     
  6. Mr. Trainiac

    Mr. Trainiac TrainBoard Member

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    To increase the appearance of length, you want your width to length ratio to be small. The more parallel tracks you have, the more square and less rectangular the yard will look. An intermodal yard does not have a lot of switching or operations going on, so you could get away with two or three tracks. Trains pull in to be loaded and unloaded, but unlike a classification yard, the cars are not rearranged. Bad order cars may be taken out, but a container is a universal load. Just make sure you have space for the truck that parks next to the container cars. Those Mi-Jack cranes, like in Point 353’s photo usually span two lanes, one rail and one road.

    An intermodal Yard takes up a lot of space, but only some of it is railroad track, so the less ‘spaghetti bowl’ the better.

    You want the yard to be proportional to the layout size. If you are building a huge layout that can handle long trains, you need a large yard to store them, but a small 4x8 would look strange with a multi-track hump yard.

    Having a single-ended yard will maximize your useful length, since you only need one ladder, not two. The switches, as you have found, take up a lot of space. Putting the yard at the ends of you layout will allow them to act as a staging yard for your intermodal trains during operating sessions.
     
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  7. Pastor John

    Pastor John TrainBoard Member

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    Thanks everyone. My thinking was directed toward building such a model in a modular format (Free-mo) and not to place on a layout at home so that, at least in theory, I wouldn't need to find space to set it up at home (which I clearly do not have). Even so, usually people say things like "build your yards and sidings to be as long as the longest trains you want to run." So, at some point, although compression makes construction easier, the trains such a yard could accommodate become unrealistically short. I was just wondering where you all have found that balance before.
     
  8. acptulsa

    acptulsa TrainBoard Member

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    1. Model a railroad/era/branch location
    where trains are/were short.

    2. You can park a train longer than the yard if you have a switching lead that extends alongside the track for a distance. The switcher can cut it into pieces and store the cuts side by side.
     
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  9. Point353

    Point353 TrainBoard Member

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    In a smaller yard, it's not unusual to make up parts of a long train on adjacent tracks, with the road power picking up one part from one track and then "doubling over' to another track to pick up the rest of the train before departing.

    Also, sidings don't necessarily have to be at least as long as the longest trains you want to run.
    The "double saw-by" maneuver will allow two trains to pass, even if both of them are longer than the siding.
    http://www.sdmrra.org/Odds-n-Ends/saw_bye.htm
     
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