Making Talus and Rock Fall for Your Layout

As you may have read in my previous posts I am currently building a pair of modules to form part of the Gosport American Model Railroad Group’s N Scale Layout.  In this post I will share with you a quick and cheap method to make some talus, boulders and general rock debris.

You can buy bags of talus form companies like Woodland Scenics in a variety of sizes but sometimes having a larger variety can be useful.  If, like me, you have cast your own rocks from rock molds (you can read more about doing this here) then it’s likely you have lots of bits of plaster left over.  I tend to fill up my rubber rock molds and this causes plaster to flow over the flat rubber and mold sides.  When I break out the rocks these pieces break off and I collect them in a tray.

Depending on what you want to use your talus or rock debris for will depend on how you color them, but for me I want to simulate fallen rock into my canyon and rock that has been washed down the river in the winter floods.  From reference materiel I have noticed that there is often less difference in the color range of the talus than in the actual rock faces.  This might be because only certain parts of the rock face are crumbling due to the different rock composition so only the softer rock will be in the bottom of the canyon.   Given that my dominant rock colors in the canyon are yellow ocher and burnt umber my talus will be a blend of these two colors.  You can read about my rock painting process here.

So here is my recipe for rock soup!  I start with a tray of plaster bits and crunch them up with my hands until they are roughly the right size.  Then I pour on a bit of burnt umber that has been mixed with water at a ratio of 1 part pigment to 16 parts water.  I give the mixture a stir to move the parts around.

Making Talus 1

The pigment soaks right into the dry plaster parts as you can see in the above photo.  Because I didn’t add a lot of pigment it only soaked into certain faces in a similar way to the leopard spotting I used on my rocks.  Next I add yellow ocher mixed at the same ratio 1 part pigment to 16 parts water.  This time I added a lot more pigment so all the bits get a good soaking, hence the term ‘rock soup’.

Making Talus 2

The rocks in the tray are stirred and shaken up so all surfaces get a good coating and the mixture is left for an hour or so to ensure the rocks get thoroughly saturated.  That way if they are chipped or broken they won’t show through brilliant white.  Once I am happy with the amount of saturation I drain off any excess liquid and leave the rock parts to dry.  This may take a day or so and it is a good idea to give them a stir now and again which will bring the wetter bits to the surface helping them to dry faster.  This processes will also work on Woodland Scenics’ talus as you can see below.  The lower tray is all the plaster debris and is a lighter color because it is a more porous material than the Woodland Scenics’ talus.  However the two will mix together well.

Making Talus 3

The area I am going to be using this on is the bottom of my canyon which you can see in the pictures below.

Making Talus 5

Making Talus 4 Making Talus 6

The river bed has been painted and is ready for some debris.  I start by dropping some of the mixture down the rock faces to see where it lands, also I add clumps in areas that would have caught rocks when the water was flowing at full strength in the winter months.  All the modules on the GAMRG’s layout are set in late summer so the water level will be low.

Making Talus 7 Making Talus 8

Next I use a watered down PVA glue in a spray or mister.  Again Woodland Scenics sell the right glue for this called Scenic Cement but you can make your own.  They also sell the spray bottle but I tend to use a basic one with a removable nozzle purchased from a garden center designed for misting plants.  It is a good idea to have a bowl of water close by so you can put the nozzle in to soak between spraying as it will start to clog up.  Because the mister gently soaks the areas it doesn’t move the rocks about.  I tend to place the talus is several stages giving the area a good soaking of scenic cement between each layer.

Making Talus 9

As you can see below I do mean a good soaking.  The talus is heavier than scenic scatter material and you don’t want it coming off the layout, especially a modular one that will get bumped around between shows.

Making Talus 10

You don’t have to wait for the first layer to dry before adding the next, in fact it is best not to as the new layer will sink into the wet glue adding to the strength.

Making Talus 11

Once you are happy with the amount and overall look give the whole area another good soak with glue and leave it overnight to dry.  Don’t be tempted to touch it until it’s dry as the talus will be very easy to dislodge until the glue has totally set.

Once all the glue has dried it will become clear and leave you with a solid scene that you can add water to or simply leave as is.

Making Talus 14 Making Talus 15 Making Talus 16 Making Talus 17

Making Talus 18

I still need to add some more vegetation at the river edge and add the water itself which I will share with you in another post.

This coming weekend, the 3rd and 4 th of October 2015 I will be at the Fareham RailEX model railway show with part of the GAMRG’s N Scale layout.  The exhibition will be at the Fareham Leisure Centre, Park Ln, Fareham, Hampshire PO16 7JU, UK and you can read more about the show here.

My new modules that I am working on will not be in this show as they still need a bit of work but it would still be nice to see if you are in the area.