How big of loco will make a 22" curve?

Discussion in 'HO Scale Model Trains' started by Oreboat, Dec 30, 2006.

  1. Oreboat

    Oreboat New Member

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    The outer loop around my layout I am going to have no less then a 22" radius curves and #6 turnouts. How big of locomotive can I run with out derailing all the time? I'd like to be able to run some six axle engines if they will handle the turns. Also how big of a steam loco can I run? Thanks Bill
  2. TruckLover

    TruckLover Mack CH613 & 53' Trailer

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    I have some Dash 9's (C44-9W) and a couple of AC4400 that I have on 22's that they seem fine. IDK about an SD90MAc though? Those are awful big. :D :D
  3. alexander

    alexander Member

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    ya, my Atlas SD24 handles the 18" curves well
  4. green_elite_cab

    green_elite_cab Keep It Moving!

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    My SD80MAC can handle it. It looks ok, but it the pilots do hang out a bit. It doesn't effect operation though. most 6 axle diesels can handle it. I can't really think of any locomotive that can't. its the 80 foot railcars you need to watchout for.

    I think most Steam locomotives can handle it, except for those with a long solid frame (2-10-4s, etc). In real life such locomotives would straighten out the rail if the radius was to tight. luckily for you, the models will only jump the tracks. However, i do not see any reason why a 2-10-4 couldn't handle it. usually the manufacturers will tell you what their model can handle. Articulateds ( Challengers, Big Boys, Alleghenies) should have no problem even on 18 radius, but they will look bizarre.
  5. LongIslandTom

    LongIslandTom Member

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    Most HO steam loco manufacturers actually use a pretty un-prototypical method to allow big steam locomotives with 5 driver axles get around 22" radius curves... They make the center driver wheels blind, i.e. the center driver wheels have no flanges. Don't know if they made provisions for you to swap in driver wheels with flanges if you do run big enough curves though.

    Personally, I think small locomotives look better on small pikes with 22" curves anyway. :cool:
  6. stuart_canada

    stuart_canada Member

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    i use to run my Athearn UP DD40 model on 22 inche but it was a tight fit, but what a road switcher lol
  7. Seaboard

    Seaboard Member

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    I run a bunch of SD40-2's on 18" they move really well to on 22". I'm sure you could run bigger on 22" track.
  8. Glen Haasdyk

    Glen Haasdyk Active Member

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    I had a trainmaster run on 18" curves at one time, but it didn't look good doing it. The 22" curves on the other part of the layout made it look okay and no operation problems
  9. TruckLover

    TruckLover Mack CH613 & 53' Trailer

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    jawdrop HjawdropO jawdropL jawdropY jawdrop
  10. Thoroughbreed

    Thoroughbreed Member

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    The 90MAC RPP frame with Athearn trucks dont do well on 22, they grossly overhang on ends and middle. They look alright on 27, but prob need 30 to look prototypical:thumb:
  11. NYNH&H

    NYNH&H Member

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    I can run an Athearn Genesis Challenger and an Athearn RTR AC4400 on 19.5" curves. Ugly, but it works. I have had the AC4400 on the club modular layout with like 40" cruves. It looks MUCH better.
  12. cidchase

    cidchase Active Member

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    Here's an informative thread on prototype blind drivers::thumb:
    http://www.trainorders.com/discussion/read.php?10,1165085
  13. NYNH&H

    NYNH&H Member

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    They also double articlulate Big Boy and Challenger, so that they can get around 18" curves. They look bad, but run well on these sharp curves. The prototypes were single articulated, and scaled down to HO, the Big Boy would need a 40" radius MINIMUM if it were made prototypically.
  14. green_elite_cab

    green_elite_cab Keep It Moving!

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    they make one in brass like that. I think my Lionel Challenger has a provisions for making the second driver set stay in one spot for realistic running.