I have noticed on many layouts; S-curves are used when a straight line or smooth curve could be used. Is this to add interest? It causes an un-natural look especially in trains pulling long passenger cars. The S-curve causes un-real overhang as the car transits and reverses in the curve.

Hi Ron

S curves are nice with large radii. They are not allowed in R1 as Märklin does not test nor guarantee this operation. The smallest allowed radius is R2.
In R1 you must have a straight track between the curves.

S curve operation is very unattractive when using small radii as long passenger cars are totally out of alignment and short coupling mechanisms are at or beyond their operating angles.
Cheers
Jean

I have an S curve without any straight track in between on my "mountain" station about 12 centimeters (5 inches) above the main layout. It's a reverse loop (with R1 C tracks) so the trains go up and down on the same track. It doesn't give me any problems with Maerklin cars and locomotives and also not locomotives from Piko, Roco and ESU. With other brands of locos and cars I've sometimes been forced to make adjustments and take precautions not to get derailments.

Ideally I should rework the section in a future project.

I have an S Bend on my layout, but it is subtle & looks good. It is a mountain scene.

When I was about 8 years old, I used to love lying down watching the 50's coaches negotiating my 5117 points. Didnt know any difference then but it was fun.

I have a very gentle S curve on my "West River" section but I used flex track to get the effect I wanted.

Then there are more long straight bits after slight kinks in the track. The same with our longest straight road, after slight kinks then there are more straight bits.

I think something has to give, even in Z gauge!

A long S-curv are far better than short S-curv because of the train length.
In fact does short train set fit better for the short S-curv.
In the real world prototype does narrow gauge trains work good with the short S-curv.
It´s all matter about train models.
Short wagons are excellent for the short S-curv.
It also depend of the layouts size in the room.
What you need is to test and practice.

S-curve in uppercase

In your case, an S curve was necessary in order to incorporate a return loop without crossing the road. The only places where I have seen S curves is where a rail line follows a river, as on the Rio Grande and Hudson river NY central track. As I said, railroads avoid S curves where possible due to cost. On a model railroad, it adds interest.

Have a look at the satellite view of the railway line through the Blue Mountains west of Sydney. It is constant S bends, plus tunnels. I have travelled this line a handful of times.

Originally it had a zig zag line to get over the Blue Mountains.

https://en.m.wikipedia.o...wiki/Blue_Mountains_Line

West of the Blue Mountains is a miserably cold place, not the hugh minus temperatures that other countries get, but the damp wet cold to the bones, which runs all the way up on the west side of the Great Dividing Range up to and into southern Queensland at times. Yes, snow in Queensland. God's own country, 'sunshine one day, perfect the next' as Queenslanders say.

The western line out of Sydney has some great little stations, you ask for the train to stop at the minor stations & on the station you flag the train down. This is the only main line west out of Sydney.

Blayney is a lovely little station in a miserably cold place which will freeze the nuts off a brass monkey.



The line through the this area is full of S bends. You have to put yourself into a meditative state or you will go mental if you are impatient.

I actually went from Sydney to Orange to look at out current new car, 268km one way. I jokingly said to the car dealer that Sydney to Dubai return is quicker. Went back to Orange a few weeks later to pick up the new car.

But at the end of the day all these S bends make this trip very slow. Electric trains stop at Bathurst, almost as cold!

The Portsmouth Direct line between Guildford and Havant in Southern England is all reverse curves because it was cheaper to build it that way to traverse the hilly terrain. After Guildford it has one tunnel, South of Petersfield, which is ‘S’ shaped as well. It came later than the main round of railway building when improved locos could cope with curves and gradients, nevertheless this (electrified) route has line speeds of 70 to 85 mph today and plenty of flange lubricators to reduce wear on the high rails. If you stand in the corridor connection between two coaches it can be quite alarming as the coaches suddenly move away from each other laterally and then line up again only to violently move away in opposite directions.
ChrisG

Let me correct myself. S-curves may be necessary depending on the terrain. Although it may be cheaper to lay straight track it may not be cost effective to straighten out terrain. It all has to be at a case-by-case basis which I'm sure railroad executives are well aware of. On my layout, I'm using M-track which has pretty tight curves. S-curves look bad using M-track. Adding a straight section of track between reversing curve tracks helps minimize the excessive overhang.

I believe every layout needs a bit of straight track & a few S bends to look better than your mistress (as a boat moored near us is call 'Mistress Again', when they sail her on the weekend they give her a good hammering and score medals!)

Even better, add a few S bend roads, it looks good and roads are easy to spray out of 150ml touch up cans with grey, white and black pre heated, pre mask the white road markings with Letraset if you can still get it or finely cut masking tape.

Z gauge:

What a great topic when applied to model railroading!!
Functional, technical issues versus aesthetic choices...

If you want to have pure ovals and straight track that is your choice and they have great interest such as above posts. So many personal choices and for good reasons all on our own. HOWEVER... when what I call "MMRIP" is in play, (Miniature Model Railroading Infinite Possibilities and then Rest in Peace) the S-curve is a staple issue in the world of Art and we would have to argue with masters of ancient Greek sculpture to do away with it. Praxiteles himself was a fan. If you want to get fancy you could tell complainers that you have a thing for "contrapposto" and it will make your layout a bit more sexy. In my view the invention of flex track was a gift to landscape creativity on MMR layouts. Gently weighted tilted hips in sculpture is also seen in landscape, it slows down the eye and invokes desire. And don't tell me that anyone here does not love trains! XD

Here are few short accessible articles on the subject. I like this one on painting because I always think of the overall landscape of the layout as a kind of painting.
She quotes William Hogarth definition of the curve; “[A] Notion in compositional theory that objects arranged on an S-shaped line suggest grace and beauty.”
https://nancyreyner.com/2011/05/13/the-s-curve/

https://en.wikipedia.org/wiki/S-curve_(art)

A bunch more references here:
https://hyperleap.com/topic/S_Curve_(art)