Small Island Scale Models : Schwerer Wehrmachtschlepper (sWS) armoured cargo version. Chapter 7: Setting the tone (Applying wet and dry mud effects to the chassis and running gear)

As I would like to display this vehicle abondoned in a field in a late 1944 ETO setting, the running gear is to receive a fair amount of wet mud effects.

I’ve never attempted a thick muddy finish on an AFV so this is going to involve a fair amount of trial and error. Watching a few videos and taking inspiration from the guys that excel in creating a cold and dirty atmostphere of vehicles set in eastern European theatres, it was clear that to pull this off I would have to step carefully.

My first choice was to decide what materials I would use. The AK acrylic textured weathering mud is a product I like and their dark mud in particular is quite a nice authentic tone out of the pot. Its easy enough to paint over too if the tone needs adjusting. It is also water based so easy to clean up if I take things a little too far.

The first steps are to add some texture. Looking at muddy vehicle images the wheels at the rear seem to pick up most of the track dirt that is kicked up and propelled over the upper track run. With this in mind I decided I would leave some wheels cleaner than others.

To get my eye in I started with the underside of the cargo platform. I could experiment with both quantities and the positioning of the product without worrying too much, as only a fraction of these areas will be visible.

Once the acrylic mud had dried I then used AK dark mud enamel and blended it in with white spirit. This product was a fair bit lighter that the acrylic mud texture colour, but the final mud tones can be adjusted with acrylic paints. I also used the speckling technique, using AK enamels with a small amount of MIG dark mud pigments to add some variation in texture.

This all looks very messy when first applied

Although I will add a sprinkling of dried mud effects the tracks will largely be covered in a pretty fresh uniform layer of mud. They were first primed with Tamiya Fine Surface Primer and then base coated in MRP-034 tank grey. I then randomly washed on, and then speckled on my pre-mixed Tamiya acrylic rain washes. Once dry an application of AK acrylic texture mud and sea grass was randomly added. I covered the cleats, trapping the mud in between, then removed any heavy build up that would have been squished as the tracks rotated.

Some dry mud pigments will be placed in mainly higher areas where the mud covering is thinnest and likely to have dried out first. I will add these once the tracks are on the vehicle.

The main running wheels received far less overall mud texture and I favoured just adding it to selected areas. Learning from my efforts on the underside of the cargo bed the effects were added in stages, slowly building up the layers. First, a random covering of textured mud paste and after it was allowed to dry, another more strategicaly placed application was added. Once dry this was followed by blending in some AK enamel dark mud thinned with white spirit.

Early stages of mud application

The front wheels received a slightly reserved first application.

The sprockets with a heavier build up of AK textured acrylic mud between the spokes.

The next step involved adding speckles of mud to the wheels. A mixture of AK dark mud splatters and MIG dark mud pigments were mixed together and applied with a cocktail stick and brush. Keeping the effect random was the aim. I resorted to masking off certain areas, but overspills are easily cleaned up with H2O.

This is the first round with two slight variations on the dark mud tone and one lighter one

The sprockets and idlers with clumps of AK textured acrylic mud between the spokes

The next round of both speckling and surface mapping will need to be more precise. I will also mix some oil paints to highlight raised detail and claw back some definition. This will also involve adding some grease and oil stains to any mud free wheel hubs.

Adding the wheels and tracks

I began by tidying up any rough mud texture areas on the chassis so the running gear could be fitted cleanly. Before any final weathering could begin the wheels and tracks had to be fitted. I had used the kit individual links, and they are a little tricky to build around the wheels and still be kept in sections for painting. In hindsight it would have been much easier to fix all the swing arms to the chassis minus just the outer wheels. If I ever build another sWS a set of Friul metal tracks will be employed too!

Before the kit tracks were fitted, I added graphite to both inner portions and sprocket teeth in areas of metal-on-metal contact. A silicone sculpting tool helped smoothly spread the graphite along the runs and onto both sides of the track teeth. As my swing arms and wheels had still to be fixed, I had to both line these up perpendicular to the chassis, and also ensure the tracks lined up as they had pre-paint. This is never guaranteed, and they both put up quite a fight! I ended up using CA glue on portions of the tracks and the fit to one of the sprockets, and over one of the idlers wasn’t ideal. I will likely look at improving these at a later stage. On the plus side having so much mud around the running gear means it was much easier to blend in all the attachment points.

The front wheels received additional enamel washes and pigments. Oil paints will round off the desired effect in a future step

The front tyres will receive both wet and dry mud effects once placement on the ground surface is determined

Now the running gear is attached I adding further weathering to harmonise the overall effect. Each wheel was dealt with separately, tidying up any overscale effects and adding more oil and grease effects with enamels. The AK texture mud was used again but in minute quantities just to blend in areas that required a little improvement. As I was conscious of how fragile the plastic track runs were I stuck to pigments, and kept the washes to acrylics only.