So, as promised, here is my follow-up describing how I created my grass look.
The materials I use are the same as used by Craig, but the method of application is different. I originally tried the all-at-one-time approach, but when I went back and reviewed it afterwards I found that some of the material that I wanted to be at the bottom had risen to the top, leaving an effect where some "rocks" were floating on top of the grass. I now build up my scenery in layers, leaving time for each layer to dry before setting down the next. It takes longer this way, but I can tackle larger areas at a time, and I have greater control over the finished appearance.
- wet water mix (water with a few drops of dishwashing detergent) in a "misting" spray bottle
- isopropyl alcohol ("IPA") in a "misting" spray bottle
- glue mix (one-third PVA glue, two-thirds wet water) in a squeeze bottle
- earth coloured acrylic or latex paint
- real "dirt" - I use stone dust, and crushed limestone materials (such as Lilydale toppings and Tynong toppings) sieved through tea strainers
- an assortment of ground foam colours and textures (mostly Woodlands Scenics)
- I first try to get the basic earth look by brushing on a coat of earth-coloured paint thinned a little (say 2:1) with water, and then using a tea strainer to sprinkle on the fine crushed limestone or rock. I work in small areas at this stage, to ensure that the paint doesn't dry before the dirt is applied. I also lightly mist each area with wet water to slow the drying time.
Around roads, railroad tracks, buildings, etc. I like to use slightly different (lighter or darker) shades of paint and stone dust to give the appearance of soil that has been disturbed by construction work.
I find it best to apply different shades of stone dust in smallish patches, to avoid getting a "salt and pepper" look.
I then leave this layer to dry for a day or two. If I think the base cover needs more work, I wet it by misting on either wet water or IPA (but only if there are no painted surfaces that will be affected by the IPA), and then sprinkle on more gravel.
- Once I'm satisfied with the appearance of the 'dirt' layer (and it will look different once it has dried), I again wet it by misting on either wet water or IPA. Then, while it is still wet, I use a coarse tea strainer to sprinkle on Earth Blend (T50) ground foam, with a patch or two of Burnt Grass (T44) and/or Green Blend (T49). Then I gently apply another light mist of wet water to hold the foam in place. Try to avid getting blobs of water landing on the foam, or they will leave round craters that will have to be hidden later on.
Then I use a squeeze bottle to drizzle on the glue mix. Work carefully to avoid creating rivers and bubbles. If you've wet the foam sufficiently then surface tension should hold the foam in place while allowing the glue to permeate the scenery. I sprinkle on more ground foam to touch up any damage, then I leave this to dry.
- After the initial grass layer has dried, I repeat the process using Green Blend (T49) in the main, but also adding patches of other shades and textures. After drizzling on the glue, I adding coarser clumps of foam to represent bushes, and then mist them so they soak up some glue.
As with many aspects of model railroading, there is no single "right way" to build scenery. This is a technique that works for me, and your mileage might vary. If you haven't built scenery before then don't put it off (as I did for far too long). The results, for the effort required, will astound you.