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Radius?

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  • Member since
    March 2012
  • 1 posts
Radius?
Posted by NP Staples MN on Thursday, March 22, 2012 8:44 PM

Could someone tell me how to measure the radius of curve track. I have been told it is the center rail or the inside rail.  In fact, someone told me it is measured from the inside of the tie, which is the closest point to the center of the circle. I want to build a simple single track circle to surround the Christmas tree. I plan to make it breakdown for storage into 4-pieces. I thought I could fit it on a 4x4 piece of plywood, but I have been told the tightest radius available in SmartTrack is larger than 4 feet. I just want to show our grand kids an old fashion train under the tree. Can someone help?

  • Member since
    February 2012
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Posted by John MS on Thursday, March 22, 2012 10:41 PM

O gauge is usually  in diameter. some brands measure differently. Ross and Atlas are center rail to center rail, Lionel O27 style track is from outside tie to outside tie, not sure about others. Atlas and Lionel offer O27 diameter on up. Ihave my Christmas layout in modular sections for easy set up and storage. the large diameter is O54 and the inner O42

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  • From: Colchester, Vermont
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Posted by Kooljock1 on Friday, March 23, 2012 4:11 AM

Who makes SmartTrack?

 

Jon  Cool

Now broadcasting world-wide at http://www.wkol.com Weekdays 5:00 AM-10:00AM!
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  • From: Austin, TX
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Posted by lionelsoni on Friday, March 23, 2012 6:46 AM

O27 is 27 inches in diameter to the outside ends of the ties, which are 2-inches long, making the radius to the center rail 12.5 inches.  The heavier track that Lionel called simply "O", nowadays often referred to as "O31" or "O30" has a 14.14-inch radius (10 * sqrt(2)) to the center rail.  The ties are 2.25 inches long; so the diameter to the outside ends of the ties is 30.534 inches.  Except for O27, the actual diameters of tubular track are only approximated by the nominal diameter.

Lionel's Fast Track is measured by the diameter to the center rail.

There is an accurate way to measure the radius of a curve from a single curved piece, which I have posted many times in the past.

Bob Nelson

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  • From: Media, PA
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Posted by Joe Hohmann on Saturday, March 24, 2012 6:55 AM

Forget the "Rocket Science". A loop of O36 FasTrack will fit into a 4x4' space with room to spare. You can just use the track itself on a white sheet if you want.

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