Which paint is better to paint car sills: choice, preparation and technology

Car sills are one of the most vulnerable parts of the body. They are constantly attacked by gravel, salt, moisture and mechanical damage. Even small chips on the thresholds can become a source of corrosion, which over time will “eat” the metal from the inside. Painting thresholds is not only a matter of aesthetics, but also rust prevention, which will extend the life of your car for years.

Many car owners mistakenly believe that any metal paint from the nearest store will be suitable for thresholds. In practice, this leads to peeling, blistering and re-corrosion after just a few months. The point is that thresholds require special materials with high adhesion, elasticity and resistance to aggressive environments. In this article, we will look at how to choose paint for thresholds, prepare the surface and apply the coating so that the result lasts for years - even in Russian winter conditions.

The choice of paint depends on several factors: the material of the thresholds (steel, aluminum, plastic), the degree of their damage, climatic conditions and even the color of the car. For example, for machines with metallic You will need base paint + varnish, and for matte SUV sills - special anti-gravel compounds. We analyzed reviews from professional painters, tests from independent laboratories and the real experience of car owners to create a checklist of criteria for the ideal paint for door sills.

1. Types of paints for thresholds: pros and cons of each type

There are dozens of types of metal paints on the market, but not all are suitable for thresholds. Main selection criteria: chip resistance, chemical resistance (salt, deicing mixtures) and elasticity (so as not to crack during deformation). Let's look at the most common options:

🔹 Acrylic paints — leader in price/quality ratio. They dry quickly (1–2 hours), do not turn yellow over time and adhere well to the ground. The main plus is high adhesion to metal, which is critical for thresholds. However, acrylic requires varnishing, otherwise the coating will not be durable enough. Popular brands: Mobihel, Sikkens, Duxone.

🔹 Alkyd enamels - a cheaper alternative to acrylic, but with a number of disadvantages. They take longer to dry (up to 24 hours), have a strong odor and may fade over time. But alkyd enamels better tolerate temperature changes, which is important for regions with harsh winters. Example: Enamel PF-115 (budget option), Hammerite (premium).

🔹 Anti-gravel coatings — specialized compositions based on polyurethane or rubber. They create thick elastic layer (0.5–2 mm), which protects against chipping and corrosion. The downside is the limited color palette (usually black or gray) and difficulty in application (requires a high-pressure gun). Market leaders: 3M Scotchgard, Tectyl, Body 950.

🔹 Liquid rubber - an innovative solution for those who want to combine protection and style. The coating is applied like paint, but after drying it forms durable matte film, similar to rubber. Perfectly masks minor defects and prevents corrosion. Popular brands: Plasti Dip, Rubber Paint. The downside is the high price and the need to update every 2-3 years.

🔹 Powder paints - used in industrial settings (for example, in factories Volkswagen or Toyota). They provide a super-durable coating, but require polymerization oven (temperature +180°C). Not used in garage conditions.

Conclusion: For most car owners, the optimal choice is acrylic paint + varnish (for colored thresholds) or anti-gravel (to protect the bottom). Liquid rubber is suitable for tuning, and alkyd enamels are suitable for budget repairs.

2. TOP 5 paints for thresholds: rating by reliability and price

We analyzed reviews on forums (Drive2, AutoWorld), magazine tests "Behind the Wheel" and "Autoreview", as well as surveys of professional painters to rank the best threshold paints. Selection criteria: chip resistance, resistance to reagents, ease of application and price.

Place	Paint name	Type	Average price (per 1 l)	Pros	Cons
1	Mobihel Acryl	Acrylic	1 200–1 500 ₽	✅ Dries quickly (1 hour) ✅ High adhesion ✅ Rich color palette	❌ Requires varnishing
2	Body 950 Anti-Gravel	Anti-gravel	1 800–2 200 ₽	✅ Protection against chips for up to 5 years ✅ Elasticity ✅ Can be applied to rust (after treatment)	❌ Limited colors ❌ Difficult to apply without experience
3	Hammerite Direct to Rust	Alkyd	900–1 300 ₽	✅ Can be applied to rust ✅ Resistant to chemicals ✅ Does not require soil	❌ Takes a long time to dry (24 hours) ❌ Pungent odor
4	Plasti Dip	Liquid rubber	2 500–3 000 ₽	✅ Matte finish without preparation ✅ Removable (can be updated) ✅ Corrosion protection	❌ Expensive ❌ Requires updating every 2–3 years
5	Sikkens Autoclear	Acrylic + varnish	2 000–2 500 ₽	✅ Professional quality ✅ Durability (7+ years) ✅ UV resistance	❌ High price ❌ Requires experience in application

Expert advice: If your car is older than 10 years and the sills already have pockets of corrosion, choose paints marked "Direct to Rust" (for example, Hammerite or Rust-Oleum). They contain rust inhibitors and can be applied directly to cleaned rust (without completely removing it).

For new cars or after complete stripping of metal, it is optimal acrylic + varnish (Mobihel or Sikkens). If you need maximum protection of the lower edge of the sills, combine anti-gravel (Body 950) with acrylic paint on top.

3. Preparing thresholds for painting: step-by-step instructions

Even the most expensive paint will not save the thresholds if they are not prepared correctly. 70% success depends on the quality of surface preparation. Skip even one step, and within six months the paint will begin to bubble or peel.

🔧 Required tools and materials:

• 🔨 Grinder or drill with brush attachment
• 🧴 Degreaser (Acetone, White spirit or specialized Antisil)
• 🧽 Rust converter (Tsinkar, Fenom)
• 🎨 Primer (epoxy or acid)
• 🧤 Respirator and gloves (required!)

📌 Step-by-step preparation algorithm:

⚠️ Attention! If there are any on the thresholds through holes from rust, they must first be welded or sealed with fiberglass putty (for example, Novol Plus 770). The paint on such areas will last a maximum of several months.

🔍 Features of rust treatment:

• 🧪 For chemical removal use rust converters (for example, Tsinkar). They convert iron oxides into phosphates, which do not rust.
• 🧽 After the converter, be sure to rinse the surface with water and dry with a hairdryer.
• 🛠️ Carry out mechanical cleaning from the center to the edgesso as not to damage healthy metal.

Critical mistake: many car owners apply primer to insufficiently cleaned rust. This causes corrosion to continue to “eat away” at the metal underneath the paint, and after 6–12 months, blisters appear.

4. Technology for painting thresholds: from primer to finish coat

When the thresholds are prepared, you can start painting. It is important to observe here temperature regime (optimally +18–25°C) and humidity (not higher than 60%). If you paint in a garage in the winter without heating, the coating may lie unevenly or crack when drying.

🎨 Step-by-step instructions:

1. Primer. Apply 2 coats of epoxy primer (eg Reoflex) with intermediate drying for 15–20 minutes. The soil must be two-component - this guarantees better adhesion.
2. Grinding the soil. After drying, sand the surface with sandpaper. P800–P1000 for better adhesion to paint.
3. Painting.
   • For acrylic paint: 2-3 thin coats with 10-15 minutes drying in between.
   • For anti-gravel: 1 thick layer (0.5–1 mm) using a high pressure gun.
   • For liquid rubber: 3-4 coats with 30 minutes drying time between coats.

Varnishing (if necessary). For acrylic paints, apply 1–2 layers of varnish (Sikkens Autoclear) for added protection.

Drying. Complete drying takes from 12 hours (acrylic) to 48 hours (alkyd enamel). During this time, you should not wash your car or drive through mud.

🛠️ Painting tools:

• 🔫 Spray gun (optimal pressure - 2-3 atm). For anti-gravel you need a gun with a nozzle 1.8–2.2 mm.
• 🧴 Compressor with a moisture separator (to prevent water from getting into the paint).
• 🧲 Masking tape and paper to protect adjacent surfaces.

⚠️ Attention! If you paint the thresholds liquid rubber, do not use solvents to clean tools - they will destroy the coating. For Plasti Dip Only a special cleaner is suitable DipCoat Remover.

What happens if you paint the thresholds without primer?

Without a primer, the paint will lie unevenly and adhesion to the metal will be weak. After 3–6 months, peeling will begin, especially in places where there are chips. The primer also protects the metal from oxidation and improves corrosion resistance.

5. How to paint thresholds without disassembling: life hacks and risks

Many car owners want to paint the sills without removing them from the car. This is possible, but requires accuracy and special techniques. The main problem is hard to reach places (for example, the internal cavities of the thresholds), where the paint may not reach.

🔧 How to paint the sills without removing them:

• 🚗 Use flexible nozzles for spray guns or aerosol cans with extended spray nozzle.
• 🧲 Carefully seal adjacent panels with masking tape and film. Particular attention is paid to the joints with doors.
• 🔍 For internal cavities use anti-corrosion sprays (for example, Dinitrol 4010 or Tectyl ML). They can be poured through technological holes.
• 🎨 Paint in warm, windless weatherso that dust does not settle on the fresh coating.

⚠️ Risks of painting without removal:

• 🔴 Uneven coverage in hard-to-reach places.
• 🔴 Paint getting on rubber door seals (can lead to cracking).
• 🔴 It is difficult to properly treat rust inside the threshold.

Conclusion: If the corrosion is superficial and you are painting the thresholds for preventive purposes, you can do without removing them. But if there is through holes or severe rust, it is better to dismantle the thresholds - otherwise the problem will return in a year or two.

6. Caring for thresholds after painting: how to extend the life of the coating

Even the most durable paint will last longer if the thresholds are properly cared for. This is especially true in winter, when salt and reagents are poured onto the roads.

🚿 Rules of care:

• 🧼 Wash the thresholds soft sponge (not with a stiff brush!) with car shampoo (for example, Karcher).
• 🧴 Apply once every 2-3 months wax protective composition (for example, Turtle Wax or Sonax).
• ❄️ After winter trips, be sure to wash off salt and reagents. Use anti-corrosion sprays for the lower part of the thresholds (Liqui Moly Unterboden-Schutz).
• 🚗 Avoid parking on tall grass or in mud - this will accelerate the wear of the surface.

🔧 What to do if chips appear:

• 🎨 Small chips (up to 1 cm) can be touched up brush or spray can with the same paint.
• 🛠️ Deep damage (more than 2 cm) requires re-sanding and painting.
• 🧴 If the chip reaches the metal, treat the area immediately rust converter and close anti-gravel.

⚠️ Attention! Never use for cleaning thresholds household chemicals (for example, Fairy or Domestos). It destroys the protective layer of paint and accelerates corrosion. Only specialized car shampoos!

7. Common mistakes when painting thresholds and how to avoid them

Even experienced craftsmen sometimes make mistakes that ruin all their efforts. We have collected TOP 5 misses and ways to prevent them.

🔴 Mistake 1: Painting on raw metal

• Consequences: The paint swells and bubbles appear.
• How to avoid: After washing, dry the sills construction hairdryer or leave in a warm garage for 12 hours.

🔴 Mistake 2: Using cheap soil

• Consequences: The soil is cracking and the paint is peeling off.
• How to avoid: Choose two-component epoxy primers (Reoflex, Novol).

🔴 Mistake 3: Applying paint too thickly

• Consequences: Smudges, long drying time, uneven color.
• How to avoid: Apply 2-3 thin layer with intermediate drying.

🔴 Mistake 4: Painting at low temperatures

• Consequences: The paint applies “shagreen” (unevenly) and does not polymerize well.
• How to avoid: Optimal temperature - +18–25°C. Use in winter heater.

🔴 Mistake 5: Neglecting to protect adjacent parts

• Consequences: The paint gets on the glass, rubber seals, and wheels.
• How to avoid: Cover adjacent elements masking tape and film.

FAQ: Answers to frequently asked questions

🔹 Is it possible to paint thresholds with a spray can, or do you need a spray gun?

You can spray paint it, but only if the thresholds do not have deep damage. For quality results:

• Use cans with adjustable spray (for example, Motip or Duplicolor).
• Apply paint from a distance 20–30 cm thin layers.
• A spray can is not suitable for anti-gravel - you need a high-pressure gun.

💡 Advice: Before using the can, practice on an unnecessary part to find the optimal distance and speed of hand movement.

🔹 What paint color should I choose for the thresholds if I want contrast?

Contrasting thresholds are a popular tuning technique. Optimal options:

• 🖤 Matte black — universal, suitable for any body color.
• 🟡 Yellow or orange — looks good on dark cars (black, blue, green).
• 🔴 Red — a classic for sports cars.

⚠️ Important: For contrasting thresholds, use matte or satin paints — they highlight less surface defects. The gloss will highlight all the irregularities.

🔹 How many layers of paint should be applied to the thresholds?

The number of layers depends on the type of paint:

• Acrylic paint: 2–3 layers + 1–2 layers of varnish.
• Anti-gravel: 1 thick layer (0.5–1 mm).
• Liquid rubber: 3-4 layers (each layer dries for 30 minutes).
• Alkyd enamel: 2 layers (drying time between layers is 12 hours).

💡 Lifehack: To check if there are enough layers, shine a light on the threshold flashlight at an angle. If there are no gaps, that's enough.

🔹 Is it possible to paint thresholds in frosty conditions (below 0°C)?

Paint at temperatures below +10°C absolutely not recommended. Reasons:

• The paint applies unevenly (“shagreen”).
• Drying time increases by 2–3 times.
• Risk of condensation forming on the surface.

🔥 Solution: If you urgently need to paint in winter:

• Use heater (for example, a heat gun).
• Choose quick drying paints (for example, Mobihel HS).
• Add to paint drying accelerator (but not more than 10% of the volume).

🔹 How to protect thresholds from chips after painting?

To extend the life of freshly painted thresholds:

• 🛡️Apply transparent protective film (for example, 3M Scotchgard).
• 🧴 Process the bottom edge anti-gravel (Body 950 or Tectyl).
• 🚗 Install mud flaps (if they are not available from the factory).
• ❄️ Wash thresholds in winter once every 2 weeksto wash off the salt.

⚠️ Attention! Do not use to protect thresholds wax polishes — they do not stick to vertical surfaces and are quickly washed off.