In this guide, we'll break down the step-by-step process of applying decals correctly to achieve a clean, seamless finish—without silvering. You'll learn why silvering happens, how to prevent it, and how to fix it if it sneaks into your project. Along the way, we'll point you to the right decals, adhesives, and finishing supplies from Hearns Hobbies to help you get the job done right.

Whether you're customising a scale model, fine-tuning a diorama, or adding the final touch to a railway carriage, decals can make or break your build. But there's one frustrating issue that continues to plague even experienced modellers—silvering. That unwanted cloudy or frosted effect trapped beneath your decals? That's silvering, and it can undo hours of careful work in an instant.

You know the feeling when you've spent weeks on a beautiful 1:72 Spitfire, painting every rivet and panel line with care, only to have those crucial RAF roundels look like they've been stuck on with frosted tape? It's maddening, really. And the worst part is that silvering often doesn't show up properly until the decal's dried completely—by which point you're thinking you've ruined the whole bloody thing.

The thing is, most modellers think decal application is straightforward—just soak, slide, and stick, right? Wrong. There's actually quite a bit of science behind getting decals to lay down properly without trapping air. Surface tension, adhesion, and even the thickness of your decal film all play crucial roles in whether you'll end up with that professional finish or another silvered mess.

Whether you're just starting out or you've ruined one too many kits with fogged decals, you're in the right place. Let's take the mystery out of decal application and make silvering a thing of the past.

Understanding Decal Silvering

Decal silvering refers to the cloudy or frosted appearance that sometimes appears underneath applied decals. This usually happens when tiny air bubbles get trapped between the decal film and the model's surface—especially if the surface isn't smooth or glossy enough. The light reflects off these micro pockets of air, making the clear backing film visible like a sheet of frosted glass. It can ruin the realism of an otherwise flawless build, and frankly, it's one of those things that makes you want to chuck the whole model in the bin.

Why does this happen so bloody often? Well, most waterslide decals are printed on a thin carrier film that needs to conform perfectly to your model's surface. When this film can't make complete contact—whether due to surface texture, improper preparation, or rushed application—air gets trapped underneath. Think of it like trying to apply cling film to a rough surface; it just won't stick properly in all the little valleys and imperfections.

Silvering is most commonly seen with railway decals and military model decals used in scale modelling, particularly on surfaces that haven't been properly prepared. The good news? It's completely preventable with the right prep, tools, and technique. You just need to understand what you're working with and why it goes wrong.

The texture of your model's surface plays a crucial role here. Even paint that looks smooth to the naked eye can have microscopic peaks and valleys that prevent proper decal adhesion. That's where your detailing parts and surface preparation techniques become absolutely essential. You wouldn't try to apply a sticker to sandpaper and expect it to look good, would you?

Surface Preparation Mastery

Here's where most people get it wrong from the start. They think they can slap a decal onto any painted surface and it'll work perfectly. Surface preparation isn't just recommended—it's absolutely critical for preventing silvering, and it's the difference between amateur-looking models and professional results.

Start with a smooth and glossy surface. A matte or uneven finish traps air underneath decals, almost guaranteeing silvering every single time. You need to apply a gloss varnish or clear coat before decal application, and this step cannot be skipped or rushed. Products from our paint collection include excellent gloss coats that create the perfect foundation for decal work.

But here's the thing that catches people out—the gloss coat needs to be properly cured, not just dry to the touch. Allow at least 24 hours for most varnishes, and longer in humid conditions. If you're working in a cold shed or garage, you might need even more time. Patience at this stage saves you hours of frustration later.

If you're applying decals to painted areas, kit paint masks can help protect surrounding details while you work on surface preparation. They're particularly useful when you need to gloss coat just specific panels or sections where decals will be applied.

Don't forget about dust and contamination either. Even the smallest bit of dust or fingerprint oil can create a barrier that prevents proper adhesion. Clean your prepared surface with a tack cloth or lint-free rag just before decal application. Some modellers swear by a light wipe with isopropyl alcohol, but make sure it's completely evaporated before proceeding.

Waterslide Decal Application

Right, this is where the rubber meets the road, as they say. You've prepped your surface properly, you've got your tools ready, and now it's time to actually apply the decal. The technique here matters more than most people realise, and rushing this step is where even experienced modellers can come unstuck.

Step 1: Cut the decal close to the image. Don't leave massive borders of clear film around your decal—excess film increases the risk of silvering and makes the decal more obvious on your model. Use a sharp craft knife or scissors, but be careful not to cut into the actual image. Some scenery lettering decals come pre-cut, which saves you this step entirely.

Step 2: Soak the decal in lukewarm water. Not hot, not cold—lukewarm. About 10-15 seconds is usually enough, but older decals or those with thicker backing paper might need longer. You'll know it's ready when the decal starts to slide freely on the backing paper. Don't leave it soaking for ages though; the adhesive can start to break down.

Step 3: Slide the decal off the backing paper. This is where things get tricky. Use a soft brush or fine tweezers to gently coax the decal onto your model. Don't try to grab it with your fingers—you'll either tear it or leave fingerprints on the adhesive side. The decal should be wet enough to slide around on your model's surface for positioning.

Step 4: Position carefully while it's still wet. You've usually got about 30 seconds to a minute before the decal starts to grab, so don't panic, but don't dawdle either. Use a clean, soft brush to nudge it into exactly the right position. If you're working with railway lettering decals, getting the alignment perfect is crucial for realistic results.

Step 5: Remove water and air bubbles. This is the critical step for preventing silvering. Use a cotton bud, soft cloth, or rubber squeegee to gently press out water and air from under the decal. Work from the centre outwards, and don't press too hard—you don't want to stretch or tear the decal film. Take your time here; it's better to make several gentle passes than to try to force everything out at once.

At this stage, applying a decal setting solution like Micro Set helps the decal bond with the surface and can prevent silvering before it starts. These solutions essentially soften the decal film slightly, helping it conform to surface details and irregularities.

Using Setting Solutions

This is where things get a bit more technical, but stick with me—understanding setting solutions properly will transform your decal work from amateur to professional standard. There are two main types: setting solutions and softening solutions, and they do completely different jobs.

Setting solutions (like Micro Set) are applied before or during decal application. They help the decal adhere better to the surface and can extend your working time slightly. Think of them as a primer for your decals—they create the ideal conditions for proper adhesion and help prevent silvering from occurring in the first place.

Softening solutions (like Micro Sol) are much stronger and are applied after the decal is in position. These actually dissolve the decal film slightly, allowing it to conform to panel lines, rivets, and other surface details. They're brilliant for getting decals to settle into recessed areas, but they can also help eliminate silvering that's already appeared.

Here's how to use them properly: apply setting solution to your prepared surface just before placing the decal. This gives you better adhesion and slightly more working time to get positioning perfect. Once the decal is in place and you've removed the excess water, apply softening solution sparingly with a small brush. Don't flood the area—just a light coat is enough.

The softening solution will make the decal look wrinkled or puckered at first. Don't panic! This is normal. Leave it alone for 10-15 minutes, and the decal will settle down and conform to the surface. If you've got stubborn silvering, you might need a second application of softening solution, but be patient between coats.

You can find quality decal adhesives and setting solutions in our collection, including the popular Micro Set and Micro Sol products that most professional modellers swear by. These aren't expensive, but they make an enormous difference to your results.

Fixing Silvering Problems

So you've followed all the advice, been careful with your application, and you've still got silvering. It happens to the best of us, and more often than we'd like to admit. The good news is that silvering isn't always a death sentence for your decal—there are several techniques you can try to salvage the situation.

The Pin Prick Method: This is your first line of defence against silvering. Use a fine sewing pin or the tip of a sharp craft knife to carefully puncture the silvered area. Make tiny holes in the trapped air bubbles—you're not trying to stab the decal to death, just create escape routes for the trapped air. Once you've made the holes, apply a small amount of softening solution over the area and gently press down with a cotton bud.

Heat and Pressure Technique: Sometimes a combination of gentle heat and pressure can help a silvered decal settle properly. Use a hair dryer on low heat (not high—you don't want to melt anything) to warm the area slightly, then apply gentle pressure with a soft cloth or rubber squeegee. The heat softens the decal film, making it more pliable and able to conform to the surface.

Solvent Rescue: For stubborn silvering, you might need to get a bit more aggressive. Apply softening solution generously to the silvered area and let it sit for several minutes. The solution will penetrate through the pin holes and dissolve some of the decal film, allowing it to settle properly. You might need to repeat this process several times for severe silvering.

If nothing else works, you've got two options: live with it and try to disguise it with weathering effects, or carefully remove the decal and start again. Removal isn't ideal, but sometimes it's better than having a permanently silvered decal ruining your model's appearance.

Prevention is definitely better than cure, which is why proper surface preparation and application technique are so important. But even when things go wrong, don't give up immediately—many silvered decals can be saved with patience and the right approach.

Advanced Finishing Techniques

Once your decals are properly applied and any silvering issues sorted, it's time to make them truly invisible. This is what separates decent model work from genuinely professional-looking builds, and it's often the step that gets rushed or skipped entirely.

The first thing to understand is that even perfectly applied decals will have visible edges where the carrier film meets the model's surface. Your job is to eliminate these edges and make the decal appear as though it's actually painted onto the model. This requires careful blending and sealing techniques.

Start with a clear coat to seal and protect the decal. Use gloss or matte finish depending on your desired final appearance, but here's the trick—apply it in thin, even coats rather than one thick layer. Multiple thin coats build up gradually and help blend the decal edges much more effectively than a single heavy application.

For models that will receive weathering effects, seal your decals before weathering begins. Weathering solutions can sometimes react with decal adhesives or cause the decal to lift, so protection is essential. Once sealed, you can apply rust, grime, dirt, and other weathering effects right over the decals just as you would over painted surfaces.

Edge Blending Technique: Use a very fine brush and thinned paint to carefully blend decal edges into the surrounding paintwork. This is particularly important for large decals or those applied over multiple colours. The goal is to eliminate the visible "step" where the decal film creates a slight raised edge.

Panel Line Enhancement: If your decals cross panel lines or surface details, use a fine liner brush to restore these details over the decal surface. This helps maintain the model's surface definition and makes the decal integration look more natural.

For competition-quality work, consider using kit paint masks to protect completed decal work while you finish other areas of your model. These masks conform well to complex shapes and won't disturb properly sealed decals when removed.

The final step is often overlooked but crucial: step back and evaluate your work in different lighting conditions. What looks perfect under your workbench lamp might show problems in natural light or different angles. Take photos of your work—the camera often picks up issues that your eyes miss, particularly with decal edges and silvering problems.

Professional Tips & Tricks

After years of working with decals on everything from 1:700 warships to N-gauge locomotives, you pick up techniques that aren't found in any instruction manual. These are the sort of tricks that separate hobby shop models from contest winners, and they're often surprisingly simple once you know them.

Temperature Control: Work in a consistent temperature environment. Decals behave differently in hot and cold conditions—too cold and they become brittle and difficult to position, too hot and they can become overly soft and prone to tearing. Room temperature (around 20-22°C) is ideal for most decal work.

Humidity Matters: High humidity can affect how quickly decals dry and how well setting solutions work. If you're working in a damp environment, allow extra time for each stage of the process. Conversely, very dry conditions can cause decals to grab too quickly, reducing your positioning time.

The Two-Stage Method: For complex or large decals, try the two-stage application method. Apply the decal with plain water first, position it carefully, then apply setting solution. This gives you maximum working time for positioning while still getting the benefits of the setting solution for final adhesion.

Sectional Application: Large decals that cover multiple panels or complex surfaces can be applied in sections. Carefully cut the decal at natural break points (like panel lines) and apply each section separately. This reduces the chance of trapped air and makes it easier to get good conformity to surface details.

"The best decal work is invisible decal work. If someone looks at your model and immediately notices the decals, you haven't quite got it right yet." - Competition modeller's wisdom

Tool Maintenance: Keep your application tools scrupulously clean. Dried adhesive on brushes or squeegees can scratch delicate decal surfaces or leave marks. Clean tools immediately after use with warm water, and replace them regularly—they're not expensive compared to the models you're working on.

Batch Processing: If you're applying multiple similar decals (like squadron markings or wagon numbers), set up an assembly line approach. Prepare all surfaces, cut all decals, then work through them systematically. This maintains consistency and prevents you from forgetting steps in the process.

Documentation: Keep notes on what works for different types of decals and models. Different manufacturers' decals behave differently, and what works perfectly for one brand might not work as well for another. Building up this knowledge over time will make you much more efficient and successful.

Quality Assessment: Before sealing decals permanently, examine them under magnification if possible. A good magnifying glass or jeweller's loupe will reveal silvering or air bubbles that aren't visible to the naked eye. It's much easier to fix these issues before the final clear coat goes on.

The detailing parts section includes many tools that can help with advanced decal work, from precision brushes to specialised application tools. Investing in quality tools pays dividends in the quality of your finished work.