'There's not that much scenery on the Rimutaka Incline, just a steep piece of track cut into a gorse covered hillside for 5 km or so. Unless one wants only to play shunt the yard at Summit (almost no scenery there either) or Cross Creek (a little bit of scenery) and never run a train on an incline.'
Now, this is an interesting interpretation of the word scenery. To say that there is not much is a bit steep. Its like saying there's no scenery on the Cass bank (just tussock) or on the central plateau (only a volcano there). Lets not forget the west coast. There is plenty of scenery there, but its mostly hidden by trees (as pointed out by a national party cabinet minister several years ago). Oh and its not easy modeling gorse covered hillsides either.
OK, with that little rant out of the way (I keep resisting writing letters to the editor for the regional newspaper, but its getting hard some days) what sort of options are there for building a layout based on the railway line between Upper Hutt and Featherston. I must sketch some of these out. The track plans will have to be condensed of course, but carefully to preserve the operational aspects of the prototype.
1) The easiest (!) is simply to model a section of incline, and have trains run up and dawn. Sounds a bit boring, but with DCC and 4 locos you could have a groups of guys driving. Add in sound (and some random wheel slip noises) and it would be a stunner. Space required (ideally) 8' by 8' in the corner of a room with an L shaped layout. It would need a helix at the back to get the trains to change levels and a fiddle yard as the composition of the trains was different depending on if it was going up or down the hill.
2) Cross creek. This was the main loco depot for the southern Wairarapa as well, so didn't just have 5-6 Fell locos.There would also be a couple of A's or Ab's and possibly a Wf for the Greytown branch. Operation limited to playing in the yard, but rearranging the trains has operational interest. As the railway was the only way of getting supplies there were also other railway movements to support this. The associated railway village should also be modeled (indeed the whole area is incredibly small in real life). It would be up to the modeler how much of the incline to model. Space required would be 8' minimum (I've done the sketches but not worked it out full size) and could expand to as much as the modeler wants. Being on a convex mountain side its a bit harder to extend it.
3) Summit. Playing trains the main aim. The summit tunnel provides an effective scenic block at one end. the layout can be extended as far back towards Upper Hutt as the modeler desires, taking in the Pakuratahi gorge and also a model of Kaitoke. Space required would be at least 8' for summit, and as much more as you wanted/had space for. at least it could be a concave L shaped layout which is easier to fit in a room.
The final option is to somehow combine the lot. I can sort of see how this could work in my head (where all sorts of funny things are possible), but its a large area required to carry it off. The arrangement of the railway on the hillsides also restricts just how things fit in a room, which may or may not be ideal.
(I must start creating some more layout ideas. There's plenty of locos now available so we can move from hand building rolling stock to actually getting this running. Dare I even mention operations?)