Unitrack return loop

[Welshbloke]

A few months ago I bought the CV1 track pack (which I heartily recommend if you have any B Train Shorties, Kato Pocket Line, the Glacier Express or trams). On the back of the package is a diagram showing how to use the 150mm radius curves and some 62mm straight pieces to create a return loop with 33mm track centres, so you can have a train disappear to the right on one line of a length of double track and then reappear on the other line, having passed around the loop.

 

It's the classic dogbone layout design but with the advantage of matching the standard track spacing, so you can build a station with three or four platform faces if you put V1 on one side, an island platform set inside V1, and either an identical setup on the other side or a plain straight track with a one-sided platform next to it. Or use the double track station set with a platform either side (although if you have space a loop on each side has more potential, as you can have one train running and two parked in the loops).

 

It made me wonder if there are similar plans elsewhere for doing the same trick with other radii of curves, as it could have great potential for a long, narrow layout? Specifically thinking the 249mm or 282mm as those seem to be the tightest you can expect scale length non-Shinkansen stock to handle.

[kvp]

It's a bit easier with Tomix C280-s, but the same can be done by using Kato R282/45 for the ballon track (6 pieces) and the last two before the straight leg should be R315/45-s. (to compensate for track spacing) The straight part of the loop could be something like S64x2+S29+S186x2. This can turn back a standard double track line on itself.

 

red = 282, blue = 315

 

ps: Tomix has a track system that makes these kind of tricks possible within the standard unit (C280 = S140 x 2) and also has a standard track spacing piece (S33), so it's possible to align any loops on any track distance. Kato tracks need more tricks to align with themselves.

[Mudkip Orange]

Specifically thinking the 249mm or 282mm as those seem to be the tightest you can expect scale length non-Shinkansen stock to handle.

 

R249 actually makes a near-perfect reversing loop, and you get a tangent between reverse curves - looks better, fewer derailments.

 

[Welshbloke]

I had a brief play with my circle of ground level 282mm curves yesterday and found that it could be done as a symmetrical loop with a couple of 124mm straights (from the double track it went 282, 124, six 282s, 124, 282, back to double track), but looked as though you'd also need a couple of the 29mm straights next to the 124s to make everything line up properly. It would clip together with just the 124mm straights but not happily.