radius track question re-asked

[Fred Bear]

I asked this question before but I had made it about as clear as a bad cup of coffee. One more time.

If a guy used 3 circles of track, 31, 42 and 54, on each end of layout, and steamlined the returns in a 30  inch strip, is there a way to lay this out? the layout framing measures 13ft by 60 inches, but the middle of the 13 ft is only 30 inches wide. The two end lay out pods are 60 inches by 55 inches. Is this possible? Does anyone have any insight? I've layed it out with the extra track I have, but without ripping up my layout, or buying more track, I'd like to know if this thing can work. Any help much appreciated, Respectfully, Jake

[Chris F]

Jake,

Your design is called a "dogbone".  I layed it out with RRTrack software and came up with the following:

O-54 (16 sections for a circle):  12 curved sections in a circle, with 2 more curved sections curving the opposite way on top and two more curving the opposite way on the bottom.  Duplicate this for the other "pod".  Connect these assemblies with 2 straights and 1 half-straight both on the top and the bottom.  The straight sections will be about 23" apart.

O-42 (12 sections for a circle):  8 curved sections in a circle, with 1 straight and 1 half-straight on each end.  Add 1 more curved section on each end, curving the opposite way.  Duplicate this for the other "pod".  Connect these assemblies with 3 straights and 1 half-straight both on the top and the bottom. 

O-31 (8 sections for a circle): 6 curved sections in a circle, with 1 half-straight on each end.  Add 1 more curved section on each end, curving the opposite way.  Duplicate this for the other "pod".  Connect these assemblies with 5 straights and 1 half-straight both on the top and the bottom.

Totals: O-54, 32 sections; O-42, 20; O-31, 16; straights, 24; half-straights, 12.

When assembled, the minimum track spacing will be about 4.5".  The outside rail at each end of the dogbone will be one inch from the edge of the table.  If this is too close, you can reduce the number of connecting straights and/or half-straights.

Note - this layout assumes a straight dogbone - an "hourglass" shape with the narrow straight centered top-to-bottom between the pods.  If you're looking at a bent dogbone, with the narrow straight offset to the top or bottom, the design might have to change.

[Fred Bear]

By darn, that did it. I did have to modify it a bit as I want the straight runs near the end of the table, off setting it. Your scheme worked great however, thank you for taking the time to do this for me. Merry Christmas to ya, Jake

[Fred Bear]

Chris F, do you have a pic of what you came up with? A schematic of sorts? Thanks, Jake