Tuesday, 12 July 2016

Building up the scenic layer - rockwork

It took me about four months to get past construction, wiring and tracklaying. That really is the hardest part and once you've got trains and turnout motors running you can focus on the fun bits.

Being a small-space layout I wanted a few easily-recognisable features that identify the area as a specific time and place. On the goods lines in Sydney the sandstone is a unique and iconic feature of the landform, especially closer to the harbour. It features in many of the cuttings on the goods lines, such as this one of 4902 by Don of the NSW Rail Rambler blog (Don's photo), taken in 1993. Although slightly later than my era, the landform and it's texture are indicative of the look I was going for. As is the bridge, but we'll come to that in a future post.

I've been hesitant to try new scenery methods in the past without either a tutorial or a practice, however I found an article in the local modelling magazine which hit the nail exactly on the head. Malcolm Smith wrote two really useful articles in the AMRM in December 2014 and January 2015 - Building Bell's Grotto Parts 1 and 2 - which outlined a way of building scenic landform reminiscent of the Blue Mountains area around the former Wolgan Valley Railway. His method uses insulation foam as a base layer, carved into a rough shape and coated with a layer of Spakfilla Rapid, available from Bunnings. Once dry, the Spakfilla is carved into the required shape.

I had a whole lot of styrene foam that I'd been hoarding for previous attempts at scenery, so I used that in place of the insulation foam.

I cut each of the layers into the required shape using a sharp boning knife retired from kitchen duties. Being longer and thinner than a regular knife they're quite useful for cutting several sheets stacked on top of each other in one go. I was going to use a hot wire cutter, but the shape of the rock I wanted didn't require much carving of the foam. These were glued, one at a time, to the baseboard from the bottom up using Selley's caulk, taking care to thin this out so that the foam would sit as flush with the previous layer as possible.

I then layered on the Spakfilla using the applicator it came with. I varied it as I went to replicate some of the pattern of rock as if chiseled out by 19th-century navvies. For the most part it was between 2-5m thick.

As this dried I also took the opportunity to start painting the sleepers, using Phillip Overton's method outlined here in his blog. This provided a nice variation of sleeper colour once the ballast was down. More on that later.

Once it dried I found the flat sections where the factory will go had formed cracks where the joins in the foam were. These were sanded back slightly, tidied with a dry paintbrush, and then coated again. One thing to keep in mind when doing this is that the thicker you go with the Spakfilla, the harder it is to keep everything level. It was dry in around three hours or so. It takes longer the thicker you apply it.

To replicate the marks left by drilling and blasting the rock apart, I grabbed a small, circular file and carved vertical lines about 5mm apart in random places on the rock faces. On the real thing these markings from the railway's construction stand out, however due to the effects of time and weathering they aren't found on every surface. It's a little feature which to me says 'this is a railway cutting.' I also carved the strata of the rock in random places as per Mal Smith's article. This was then cleaned with a dry brush to provide a neat surface for the paint.

Using artist's acrylic paints, I mixed up some yellow (tablespoon-ish) with a dash of white into a takeaway container and added water until it reached a milky consistency - about 1 cup of water - to make a paint wash. This forms the base colour (visible on the left-hand side of the scenery below) and was dabbed onto the vertical surfaces and brushed onto the horizontal surfaces with a soft-bristled brush.

I then mixed up the same again, with hardly any white at all and a dash of brown to get a more golden colour. Once the previous layer had dried, I went over the entire rock works again, using the same dab/brush sequence.

Then came the grime layer. For this I grabbed about a tablespoon of brown, added a dash of black and a dash of white and then the water to get a grey-ish, brown-ish colour. I then dabbed this onto the vertical surfaces of the cutting, trying to avoid the horizontal indentations as much as possible. The wash naturally ran into the vertical "drill" lines, which helps to make them stand out in the finished product. I picked a few random places and try to make the rock darker here and there to vary the pattern.

 It looks pretty dark at this point...

...but once dry it comes out lighter and the variation in pattern is more easily spotted. If you're trying this yourself have one go at it with the dark wash and then leave it. This is one of those jobs where putting all the tools down and walking away from it completely for a few hours is essential.

The avoidance of the horizontal indentations earlier provides a pleasing representation of parts of the rock less exposed to the grit from the passing trains.

To be continued...


  1. Great attention to detail with drilling grooves, rarely seen on cutting models.

    1. Thanks Ben! When I was going through photos of the goods lines they were something that just kept coming up. It's a good little feature to pinpoint a time and place.

  2. Ben, inspirational work! You have really nailed the drilling grooves. Glad the 49 class photo helped a bit - though I can't say I was concentrating on the rock formation when I saw the GM! Don

    1. Thanks Don! During the build I had several different windows of your blog open on the screen, each with different photos from Rozelle and Darling Harbour. I'm sure I'm not the only modeller who has come to rely on your photos for detailing either! Thanks for sharing your collection so publicly.