O72 Lionel Suggested Layouts

I have posted ths once previously.  In my opinion, this is the best compact O-72 layout.  It specifically uses Atlas track sections, but this arrangement should be adaptable to other track varieties.  But the larger interior oval is O-60.  Please note that if you want multiple ovals in O-72, you may exceed the 8' that you want.  If you can have 2 simple ovals, there can be O-72 track on both with 4" track centers.

With an 8' x 12' space there's room for a double track 072 oval.  With a 3rd elevated 072 loop or figure 8.  The elevated line is going to need custom made piers; you can make them from basswood.

Thanks. Do you have a SCARM file you could upload?

I do not have any file for this.  I was only able to obtain it as shown.  It is drawn exactly for Atlas track pieces, so it should be buildable as shown.  Is there anyone here who could volunteer to try making a file?

@IcedCorn

Is this what you would like? It is in Fastrack only...

Just a thought - there are a lot of plans out there (like in Kalmbach's "101 Track Plans for Model Railroads" or online) that are small HO layouts with 18" radius curves - the HO equivalent of O-72 curves. Unlikely you'll find an exact plan you'll end up using, but perhaps some of the plans for small layouts will give you an idea of what might work for your layout.

To try and state this is the simplest geometry, we have a space 8 feet wide.  3 foot radius curves take up 6 of the available 8 feet.  In track planning, we try to maintain a track centerline 4" from the edge.  So this leaves us with 16 inches of straight track on the end.  That is the basis of our plan.  So we make the outer "oval" 7'4" center-to-center.  We then connect to the inner circuit which is either O-60(Fastrack) or O-63(Atlas).  This also has 16 inches on the end, including a switch.  So now the inside can be another continuous circuit, O-36, as shown on our original sample plan.  Or you can fill the inside with yard tracks or maybe a turntable.  There is no need to go around looking at HO plans.  Our O gauge double circle track geometry can only be as above.

@wjstix posted:

Just a thought - there are a lot of plans out there (like in Kalmbach's "101 Track Plans for Model Railroads" or online) that are small HO layouts with 18" radius curves - the HO equivalent of O-72 curves. Unlikely you'll find an exact plan you'll end up using, but perhaps some of the plans for small layouts will give you an idea of what might work for your layout.

Just to clarify, as the radius/diameter stuff can trip folks up...  18" radius is 36" diameter, which is about the same as O-36 Fastrack curves.  An O-72 circle is approximately 6 feet in diameter, which would be 36" radius.

Keep in mind that the measurements are approximate, and 3-rail trains often have a lot of overhang, even on O-72 curves.  Also, re-scaling a plan can create challenges with switches and grades. 

@IcedCorn posted:

I was hoping for inspiration for a lay out that just wasn't an oval, but I'm not having any luck. I don't have much space (maybe 12x8) ... all of the track I'm putting down needs to be O72 - no inner loops at O36. Thanks for any ideas or suggestions you can give!

Create a stable wormhole that leads to another dimension?  Seriously- all you can do with O72 in 8x12 is a short oval.  Forget about grades.  You could add a little elevation for effect.  But to get clearance for an over-under, they would have to be toyishly steep.  I would even be tempted to ditch the second mainline in favor of a reverse loop, or more sidings and scenery in the center.

Every catalog is filled with scale articulateds and ABA diesel sets; I guess people must buy them.  To me, that's like going to the pet store and coming home with a Great Dane.  Beautiful animal, but do most of us have the house and backyard for it?  My $.02.