New layout

[Nine Elms]

Thank you all for your advice and comments. I am coming to the conclusion, that to include an incline on my layout could be fraught with problems, I will go level. So, it is back to the drawing board.

I could well be back with further questions.

John

[Mountain Goat]

Regarding gradients, I have always experimented with my own locos and stock as I have found that each scale and gauge is different and also it depends on what one expects to pull and the pulling power of the locos.

As a guide I used to get the weakest loco and had it pull what I wanted it to pull as an acceptable load, and kept increasing the gradient slightly on a test track until I had a rough idea where the limits were and went from there.

The main criteria is a gradient which will allow everything to run in the length that allows sufficient height to allow for crossing a lower track if this makes sense? Narrow gauges do have this as a dissadvantage in a way because body heights are taller than their gauge width, so a little extra care in the layout design is needed to overcome this, but on the plus side, narrow gauges train weight in what one may expect them to pull is usually a lot lighter than their standard gauge equivalents so gradients can in theory be increased.
Outdoor lines in any scale are a whole new enviroment when it comes to slippery track, but outdoors one normally has a lot more space to ease the gradients.
But what I do say is to experiment for yourself and is worth buying a budget loco with a few items of rolling stock and a few pieces of track to experiment with, as budget locos are normally the weakest pullers (Not always) so one can get a "Feel" of what is possible or not. I did this when I tried modelling in H0e as I did not initially have a clue as I was used to 00 but though I had briefly tried N, H0e was initially a bit of a mystery, and apart from narrow gauge having overly tall bodies so needed additional height compared to their narrow gauge, I found them to be quite good hillclimbers compared to what I initially expected. I did not stay with H0e for long as I decided that 0-16.5 was all in a better proposition for my individual requirements.

But going back to gauges, scales and gradients, nothing really beats ones own experimentation, as we all have different modelling needs. Take 00 for instance. (And I maybe a little out of date in 00 models but the same principle exists). The same motors were fitted in Lima DMU's as they were in their mainline diesels so a diesel railcar has the power to pull the same length trains (As long as it was heavy enough) as a diesel designed to pull long trains, so if one has a simple layout and is only interested in running DMU's into a city terminus as an example, one will get away with far steeper gradients than someone who wanted to model a steam era main line as in general, model diesels in this scale can usually outpull their steam equivalents (Though there are exceptions) so it really depends what one wants to run and model in as some are better pullers and naturally pull lighter trains than others, so the max of 1 in 30 ratio is a rough guide which some may find their trains not able to go anywhere near that gradient, while others could find they can possibly go steeper if they happen to model the right stock that have a bit more ability in climbing.
The same thing goes for real life trains as after many trials where early morning trains were stuck on the Pembroke Dock branch due to the need to climb the steep hill out of Tenby on icy morning rails, and after trying all their units the class 150's were found to go up the hill without problems. Once that first service had passed, they could send any of the other classes down there without issue as by then the ice had cleared. They only found this out by experimenting to find a solution after other classed were finding themselves stuck.

Anyway. The only real answer is to experiment with the weakest loco pulling an "Acceptable" load.

Of course a flat layout is not going to have gradient problems and though one can alter the scenery to create the impression that it is not flat, where is the fun of that when one can have the challenge of getting trains up a hill? Which is why I am looking forwards to a house move so I can build a permanent layout again that has a gradient to climb as I love the challenge as it is fun!