One of the big hurdles with building models of older NZR passenger rolling stock is the platform railings. These are quite hard to get right in S scale let alone scaling down even further. Here's how I do it.
First up get a piece of MDF or cardboard. Draw in pencil the shape of the railings, and use a knife to cut a V grove in the MDF. The brass wire is then cut to size and laid into the groves. I used a piece of brass microstrip for the base.
To solder everything together, paint some flux on the joint, and just quickly touch the soldering iron to the joint. If all goes to plan it should go 'pfftt' and you will get a nice joint. Don't worry if its a bit blobby as you can clean that up later. Try not to inhale the fumes as they are not that nice.
After you have done all the joints, carefully remove from the jig and clean up with a small file. The next step is to carefully file the tops of the vertical rails till they fit nicely under the roof without distorting anything. Then just glue them in (I used superglue for the bottom strip, and 5 min araldite for the tops.
I've also added some details like number plates, dog boxes, door handles etc. The handrails on the sides, ends and doors will have to wait (mainly till I can work out where my fine wire has vanished to).
Next up will be painting and weathering.