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3 1/2 gauge Radii

Discussion in 'Miniature Railways' started by celticboy, Dec 4, 2008.

  1. celticboy

    celticboy New Member

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    I would like to build a small line in my garden, but need to know the min radius that a 3 1/2 inch gauge 2-6-2 tank engine would require! Would it run around a 12ft radius or is that to tight for this loco?
     
  2. What is the fixed wheel base Ie distancew between leading and trailing drivers
     
  3. andrewtoplis

    andrewtoplis Well-Known Member

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    Wheelbase length multiplied by 25 should give you a rough idea of the curves it will take.
     
  4. glastonrail

    glastonrail New Member

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    Hmm... ...

    Well, a Tinkerbell (7.25" gauge, 0-4-2T) normally has a 17" fixed wheelbase, which gives 425, which divided by 12 (12 inches to a foot) gives a radius of 35.416r feet (say 35' 6" for sake of argument). Now while I don't doubt the theory for ideal minimum radius - I know little about the theory of locomotive design, our two happily go round 25ft radius curves, given the standard 1/8" gauge widening.

    I do know of a Tinkerbell that had the wheelbase shortened to 14" and was put round 12ft radius curves... ... :smt104

    So if celticboy's 3.5" 2-6-2T has a fixed wheelbase of - say - 12", the minimum radius for the fixed wheelbase alone would be 25 feet?? Celticboy hasn't mentioned which design he is on about using (there are several), but I would personally hazard a guess that 10' would be fine, depending on the amount of play on the pony trucks... ...

    Cheers,

    Dom
     
  5. celticboy

    celticboy New Member

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    Thanks for your advice, alot of help. It looks like my minimum radius of 12' could be workable.

    Thanks
     

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