Using Different Mediums To Achieve Realistic Rust Effects

In this tutorial, I'll be demonstrating some weathering techniques to achieve a realistic rust effect using layered mediums - sand texture gel, acrylic paints and Humbrol weathering powders. Of course, you can use them however you wish but I did the gel in step 1, acrylic paint as step 2, then weathering powders as step 3. You'll be able to see the effects at each stage should you decide to have a go yourself.

Why should you rust things as a modeller?

🔧 1. Realism! In the real world, metal barrels left outside naturally rust over time. By replicating this, the model looks more authentic—weathered, aged, and believable. Pristine barrels often look too new and out of place in scenes meant to feel lived-in or industrial.

🧩 2. Storytelling… Rust tells a silent story—perhaps the scene has been abandoned, or it's an old, overused industrial yard. Rusty barrels suggest neglect, time passing, or even danger (think chemical waste or war zones). It gives the viewer more to imagine.

🎨 3. Visual Interest. Rust adds colour, contrast, and texture. It breaks up flat paintwork with subtle oranges, browns, and pits. It makes the model more eye-catching and dynamic.

🎯 4. Skill Showcase… Rusting barrels is a great way for modellers to practice and show off weathering techniques—dry brushing, sponge weathering, pigments, oils. It's satisfying and adds a professional touch.

These methods can be used to weather flat or 3D surfaces, such as the varied-size 3D-printed barrels I have used in my examples below. This is a great project with really effective results - it's well worth the time spent adding the details… Let's get stuck in!

Materials used:

• Barrels
  I used:
  AX143-OO 45 Gallon Drums (Pack of 10) - OO/4mm/1:76 (I used Green)
  and
  Gaugemaster GM493 Barrels (Pack of 10) - OO/4mm/1:76
  
  You can buy wooden 3D printed barrels in other scales here:
  AX073-N 3D Printed Large Wooden Barrels (Pack of 20) N/2mm/1:148
  AX073-O 3D Printed Large Wooden Barrels (Pack of 20) O/7mm/1:43
  AX073-OO 3D Printed Large Wooden Barrels (Pack of 20) OO/4mm/1:76
   
• Windsor & Newton Sand Texture Gel
   
• Acrylic paints
  
  For the base:
  Burnt Umber
  Burnt Sienna
  Venetian Red
  
  For the highlights (lots of blending):
  Titanium White
  Yellow Ochre
  Cadmium Yellow Hue
  Primary Yellow
  Metallic Brown
  Metallic Yellow
  
  For the weathering powders:
  Sap Green
  Hooker's Green
   
• Humbrol weathering powders
  Humbrol AV0015 Weathering Powder Chrome Oxide Green
  Humbrol AV0019 Weathering Powder Dark Rust
  Humbrol AV0018 Weathering Powder Light Rust
  Humbrol AV0017 Weathering Powder Dark Earth
   
• Small paintbrushes
   
• A paint palette or reused plastic tub - for dabbing paints and gel onto and mixing
   
• Plenty of kitchen tissue - for getting paint the majority of paint off your brush for weathering. Kitchen towel is great as it's a bit more abrasive for rubbing off paint on plastic as well
   

Method 1: 
Sand texture gel and acrylic paint

Step 1. Apply the layer of sand texture gel

First things first, paint the barrels with a coat of sand texture gel to create dimension. Rusty metal bubbles often seen as paint blisters on metal surfaces indicate rust forming underneath the paint, potentially from moisture or damage. These bubbles can signify that the rust has progressed from the inside out, creating larger holes when the top coat is removed. This is the effect you're trying to recreate with some gel. 

Here's the before and after of the Gaugemaster barrels - set aside and leave to dry (it will dry translucent). I was very generous with the gel as I could scrape it off if too much - use however much you'd like!

When dry, apply your acrylics in layers, using the dry brushing method. Peel off and scrape off any gel in very small areas to replicate damaged and rusted metal before, during, or even after applying paint. There's no right or wrong! Just experiment.

Here's an example using Yellow Ochre on the green textured gel barrel… Applied and blended with a finger…

Burnt Sienna mixed with Yellow Ochre applied onto a black, dried texture gel barrel, and blended out with fingers… I also scraped away some of the dried gel for a “clumping” rusted effect…

Method 2. 
Acrylic paint only

Step 1. Apply the base layer of acrylic paints to the barrels

Start by painting the barrels a base colour using your acrylic paints. The base colours I used were: Burnt Umber (dark brown), Burnt Sienna (red brown) and Venetian Red (orange/red brown), on all of the Scale Model Scenery and Gaugemaster barrels.

One of my favourite results here are the green Gaugemaster barrels with the Venetian Red painted on the top, and left to dry. Then scratched off the paint in small areas to reveal the green again, see below! Easy-peasy lemon squeezy…

Step 2. Acrylic paint highlighting

For the highlighting, I picked a selection of lighter colours in assorted shades of yellow, and metallics. These were - Titanium White, Yellow Ochre, Cadmium Yellow Hue, Primary Yellow, Metallic Brown and last but not least Metallic Yellow. You might be thinking, Gordon Bennett that's a lot… It is! You may only decide to use one, but I wanted to experiment with lots of colours. You don't need them all by any means.

Option 1: Using the dry brush technique, pick up a dab of paint on your brush, swirl it on tissue so only a tiny bit remains, and sweep along the barrel wherever you'd like. The barrel join lines and the lid textures make for really good areas to highlight. You should always try and highlight along areas that light would bounce off in real life. 

Here's the green barrel, with dried acrylic paint scraped off, as an example, with very light Yellow Ochre dry brushed on…

Option 2: Dab the light or metallic paint directly onto your barrel and blend it out - or don't blend and leave it stippled.

Here's a Burnt Sienna painted barrel, where I layer up paints Yellow Ochre/White mixed, smudge out with fingers, and Venetian Red, then smudge out with fingers….

Then rub the acrylics off abrasively with a tissue…

Or, dry brushing metallic paint in Metallic Brown along the joints and then applying Venetian Red over the top for rust…

Or, painting the Venetian Red base barrel liberally; Metallic Yellow and Titanium White were striped directly onto the barrel, then rubbing off with tissue…

Both options give good results, so give it a go and see which you prefer.

Method 3. 

Weathering powders

There are no steps for this… It's pretty straightforward! Be quite generous with the powder and stipple it onto the wet or dry acrylic paint in random places. These powders are fantastic. I did a swatch of them wet and dry and they're really vibrant with a matte finish - wholly recommend if you're looking for good quality powders.

I used Oxide Green for green rust effects, Light Rust for bright orange rust effects and the Dark Rust/Dark Earth to replicate dirtier areas on the barrels. 

Weathering powder can be fantastic for dulling down anything too bright and making them "dirtier" - see below 3 examples of barrels; before image on the left and after image on the right, using the Dark Earth powder…

I told you green was my favourite! Doesn't it look brilliant? Here's some more examples using Light Rust powder…

See them all below when dried…

I hope you'll give this a try yourself - it's great fun. Whether you decide to use just acrylic paints or get stuck into some weathering powders, the results are truly worth it. They'll look superb on your scenes!

Thanks for reading and happy modelling!