Tubular Track Geometry Question

To the best of my knowledge, yes they are half curves.

 

Sixteen of them make a full circle. They are 22.5 degrees.

 

A trick you can use with these:

 

Coming off an o72 switch, if you use an o72 curve to "get back to straight", you will have considerable distance between your main track and the track coming off the o72 switch. If you use a half o31 instead, the tracks will be parallel and much closer together as both the full o72 and the half o31 have the same degree of curve - 22.5.

 

This has always been a puzzle. A half curve tubular 031 is the same as slightly more than half a regular curve. The half curve is equal to two tie lengths on a regular curve. The length of the rails that span 2 ties is more than half the curve section.

So if you make a full circle out of the "half" pieces, you will end up with a slightly bigger circle than if you went with the standard curves.

If you use a half o31 instead, the tracks will be parallel and much closer together as both the full o72 and the half o31 have the same degree of curve - 22.5.

I always wondered about that.....


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Thanks Harry, this is exactly what I was wondering.  I was hoping to pair it to an O72 switch in the other direction and get back to the O31 "rhythm", if you will.  In other words, use an O31 half and three O31 curves to go back 180 in the other direction after taking the turnout.

 

Assuming it is indeed 22.5 degrees, doing what you said should work perfectly too.

 

I believe what you say would in fact make sense but wasn't sure.  Anyone have any O31 halves to check?  I want to be sure before buying online

I just checked and two together is about one inch larger than a single o31 45 degree curve. I think the difference is so small that when using just one as a 22.5 degree piece you are fine. I think sixteen of them would make a large circle than o31. Two of them together appear to be a bit of a broader angle than one piece of o31.

 

Thanks Harry!  As JohnS said, I could always trim it (and slide the tie) if I had to since it's relatively easy to modify tubular track.  But at that point, I could always take a regular O31, cut it in half and add an extra tie to make two halves.

 

You'd think a half curve would actually be a half curve...oh well.  Thanks again everyone.