How to make hills – 5 steps from model making gurus

How to build model hills for your railway, the definitive guide.

Does your model railway hill building feel like mountain climbing?

In the rain…

If you want beautiful hills and valleys but are struggling with ugly bumps that look like lumpy molehills and messy disasters these budget-friendly techniques by model-making gurus are for you.

“I will lift up my eyes to the mountains; From where shall my help come?”

Psalms 121:1

It took me a long time and lots of disappointment before the hills, mountains and valleys on my early railways lived up to the splendour of my imagined micro vistas.

While I had dreams of trains racing past gorgeous rolling hills and verdant valleys, the reality was usually a terrain that resembled a school Papier-mâché experiment gone horribly wrong.

Where I wanted gentle elevations and slopes, ugly gappy paper folds reigned. Rocky outcrops heralded yesterday’s newspaper headlines and plaster lumps lay everywhere.

At the end of one unfortunate episode, my OO gauge train layout looked like the scene in Close Encounters where the protagonist, Roy Neary — wonderfully played by Richard Dreyfuss — builds a mountain in his living room.

Frustration got the better of me and I set out to become the Turner of model building landscapes.

I scoured every corner of the Internet for tips; devoured every book on the subject, and spent days, weeks, and even months, experimenting and seeking out insight and knowledge.

While my quest to craft the perfect hill continues,  I’ve accumulated a library of techniques from budget tips to expert guides from some of the best model-making gurus, here they are in this ModelRailwayEngineer Whistlestop Tour to making model hills.

1. Start with reality

The first recommendation, from just about every serious model builder, is to check in with reality.

Surround yourself with pictures and photos of real terrain, hills and mountain landforms. Even better, get out to the countryside and see them for yourself.

From these pictures and views, sketch out the basic shape of the hills and geometric shapes that constitute the core of these hills and how they’ll integrate with your model railway.

Most importantly, note their size in proportion to the rest of the landscape. If you’re really dedicated get hold of an Ordinance Survey or another terrain map that shows elevations and heights.

Hills and mountains are often a lot bigger in relation to surrounding scenery than we think and if not sized appropriately your hills will end up looking like a stilted bulge in your terrain. You might have to condense them down but do so while keeping the overall proportions in tact.

If you can’t get out yourself, search Google Images and Flickr, there are thousands of pictures to work from.

2. Prepare the profile

Once you know the underlying shapes, crate the underlying profile form for them.

The old-school traditional technique was to make the profile from wood (particularly for OO and HO gauge layouts).

The approach is to create a foundation framework of vertical supports shaped to the underlying shape. These are fixed to the baseboard or frame with horizontal buttresses, as seen in the figure above from legendary modeller John Ahern who outlined the approach in Miniature Landscape Modelling.

This creates a solid, stable, base on which to build but is heavy and naturally requires the necessary wood which can put the cost up, assuming you don’t happen to have any lying around.

The modern approach is to use Styrofoam; the low-density type used in packaging for furniture, which is where I get mine from.

This typically comes in sheets, and it’s a simple matter to glue and carve the polystyrene sheets to the height required and profile required with a knife or ideally hot wire cutter.  The shapes made  can be fixed to the baseboard with either wood glue (PVA).

Whether you use wood or polystyrene, remember to leave space for tunnels through the hills if that is your plan. And this isn’t just a case of leaving a track-sized gap through the middle for making tunnels).

With the foundations in place, it’s then a matter of creating the shell that wraps over foam or wood to create the surface detail and textures.

3. Build the bedrock

With the underlying profile and shape of your hills created, it’s time to build the bedrock, the layer on to which ground cover, soil and rocky outcrops can be placed.

Covering wood profiles

If you used wood to make the profile, the best budget technique I’ve found is the “matrix” method described by the appropriately named 30-year model veteran Tony Hill in his excellent book Creating Realistic Landscapes for Model Railways. 

In his book, Tony describes using strips of 15mm wide card cut from cereal packets and laying them down horizontally across the wood, securing them in place with hot glue.

Once the horizontal strips are in place, weave strips of the same card vertically between the horizontal pieces, using PVA to fix them to the other strips.

Alternatively, you can make the ‘matrix’, as Tony calls it, separately and then glue it over the wooden framework. This is how I tend to do it, it’s easier to weave the vertical strips in and out of the horizontal pieces when not in situ.

The only issue with the cardboard matrix method is that when spanning wide gaps, the cardboard can sag.  If you have large spaces between the wooden supports, chicken wire may be a better solution.  This creates a studier bedroom layer on which to build but needs securing with nails and is harder to work.

Over the matrix or chicken wire, Tony recommends using two-ply tissue. PVA is applied to the cardboard and the tissue paper is pressed into place so it bonds with the glue.

While the tissue is still damp, a plaster mix of Artext is then painted over it. This is repeated several times until a realistic texture is achieved.

Bedrock layer for polystyrene hills

For polystyrene profiles, plaster cast bandage aka Modock or plastercloth, is the most common technique used. This can be made from old fabric or bought ready made.

Just soak this is water and lay it over the polystyrene shapes and leave to dry. It glues in place. You might need several layers to create an effective covering.

I lay these on in vertical strips first, then horizontally. Once dry, I then gently skim the surface with modelling plaster, normal plaster by very fine, to create a smooth surface and fill in any small gaps.

4. Adding soil and grass 

Once the bedrock layer is dry, it’s time for colouring and grass.

Painting the surface may seem excessive given it’s going to be covered in scatter or static grass, next, but applying a coating of brown acrylic will hide any gaps where the scatter is missed and looks more convincing overall.

For soil colour, I use a combination of browns and greys. For this watered down cheap children’s acrylics can be used as they won’t be seen much and you want good coverage.

With the soil colour in place, grass is added to slopes and plateaus by applying a thin coating of PVA and then sprinkling scatter or applying static grass.

Further details and steps for this approach are in Tony’s book which I recommend for anyone struggling with scenery construction.

I should add that I’ve always struggled with the colours of grass until I got my hands on Miniature Landscape Modelling by John H Ahern — regarded by many as the first truly scenic layout modeller.

Reading John’s book was a revelation.

When he suggested, in his now out-of-print book, that many greens are “too blue for grass” it was if he’d been reading my mind.

John’s tip, on page 30 of my well-used copy of his bible, is to start with yellow as the base colour — rather than green — and then mix small amounts of green into this until the desired shade is obtained.  Bingo.

Now I mix up some paint, starting with yellow as prescribed by John, to the shade I want (using the pictures taken earlier as reference) and dry brush or dab the scatter or static grass with the paint.

Alternatively, find a fine mist sprayer (perfume spray bottles can be quite good if you can find one where the spray cap can be removed so you can to fill them) and apply a lite application of the paint using this.

Rendering rocky outcrops

Of course, not all hills and mountains are covered in vegetation.

For exposed rocks outcrops, leave off the scatter or static grass but top with rock-coloured scatter. John’s advice is to use fine grain sand and tree bark is also very convincing and which I’ve covered in a previous tip in DIY rock making

An alternative for pronounced outcrops or crags is to use aluminium foil. Take a sheet of it, scrunch it into roughly the shape required and securing to the bedroom layer with epoxy glue. Once secured in place, Artex or plaster of pairs can be applied and shaped using artist’s pallet knife. The plaster can be scraped with a wire brush or knife to create further texture and strata lines.

Once the plaster is set, it’s then painted with black wash and topped with acrylics reflecting the main colour of the rocks required (grey for granite and slate for South West Britain England, Yellow/brown for Staffordshire-Worcestershire sandstone for example). Finally, dry brush it in a highlight colour to finish.

5. Layer on low-level foliage

Another aspect I’ve struggled with, particularly on my current layout, is finding a way of creating low-level shrubs and bushes that don’t appear too big for the N and OO scale layouts that I most commonly work on.

One of my layouts is Cornish mining themed and I wanted one for some of my hills that surround the mines to be covered in gorse — as per the picture left — but off-the-shelf pre-made, bushes look not to mention their price.

I failed to find something that looked realistic until I was, by chance, again reading The Story Of Craig and Mertonford Railway by the late P. D. Hancock. He was one of the earlier pioneers of narrow-gauge railway modelling and I love reading this book for the tales he creates around his railway.

While browsing through it one evening looking at the pictures I happened to read the section where he describes using surgical lint for grassland. I’d skipped this section before and it was only while re-reading it, and having been battling with the challenge of finding a suitably scaled gorse look-a-like, that the idea of using lint for sprawling bushes dawned on me.

I’m still testing the technique but the tiny fibres of lint, once coloured dark green and with small amounts of yellow scatter (to represent the flowers), have so far proved very effective and I’m very pleased with the results.

6. Top with taller plants

With the low-lying vegetation and grass on the hills and mountains taken care of, other vegetation can be added, namely trees and taller bushes.

This is particularly effective for hills towards the front of the layout. Think about natural scenes, it’s only in the foreground that you notice the trees and bushes.

For hedge rows, the best budget tip I’ve come across is DIY model railway hedges. Essentially, go and cut up some floor scrubbers. See the post for more details and a great tutorial video.

For tall vegetation, there’s a wonderfully simple 5 step technique to making your own model railway trees. As with the hedges, there’s a video to help.

So that’s it, now it’s just a case of positioning the bushes, hedges and trees based on the original photos and you’ll have very realistic-looking hills and mountains produced on a budget. Send me your pictures if you used any of these techniques.

Summary

• Have a good idea of what you want your hills to look like, ideally based on the real thing. Use photos as references.
• Build the shape (especially for mountains), using wood or polystyrene foam.
• Onto the wood or foam, create the surface layer with a card matrix or plaster cloth and paint this a soil colour.
• Add scatter and static grass.
• Then add common household sponges and similar for low-level vegetation.
• Finally, add bushes and trees.

Conclusion

Following these steps to making hills and elevated terrain and you’ll give your model railway or diorama height and depth that really add to its authenticity, scenic interest and visual appeal. Give them a go and let me know how you get on. Equally, if you have any other tips on how to create hills I’d love to hear them.

Picture credit: Grey Hills in the background,  Mark Hughes; Cornish mines, John Stratford

> A final, personal, note: I spend a huge amount of time testing, photographing, writing and researching techniques for these articles and pay for all the running costs of MRE out of my own pocket. If you found this article useful you can support me by making a donation on my fund-raising page. Thanks and happy modelling, Andy.