ᐅ KALLAX stained with watercolors after an accident – how to repaint it to look like new?

As a supplement on the topic of adhesion primers: There are special adhesion primers for plastics, which can indeed be found in well-stocked hardware stores, often labeled as "primer for smooth surfaces" or "adhesion promoter for plastics." You should ensure that the primer is compatible with your chosen paint – usually, acrylic or synthetic resin paints work well with these primers.

Regarding sanding: Use sandpaper with a grit of 220 to avoid damaging the surface too much. After sanding, be sure to thoroughly remove dust, ideally with a slightly damp cloth, so the primer can be applied cleanly.

Another tip: Test the materials beforehand on an inconspicuous area, as the coating on KALLAX can react differently. Also, sanding can slightly wear down the edges, so please be careful when working there.

Finally, I recommend a matte finish paint, as it better conceals minor imperfections. Glossy paints tend to highlight every unevenness more clearly.

The procedure for painting KALLAX shelves after watercolor stains can be summarized as follows:

1. Lightly sand the surface (grit 180-220)
2. Wipe off dust completely
3. Apply an adhesion primer specifically designed for smooth plastic surfaces; it’s better to apply several thin coats than one thick one
4. After the primer has fully dried, apply 2-3 thin coats of acrylic or alkyd paint of your choice
5. Allow each layer to cure properly in between coats

A common mistake is applying paint too thickly, which causes runs and stains. It’s best to use high-quality furniture or plastic paints, as they adhere better and are more durable.

If you’re looking for paints, many manufacturers, such as Bondex or Clou, offer suitable products.

My brief recommendation: sanding, adhesion primer, then acrylic paint. Done. No experiments with the paint, as KALLAX is generally difficult to refinish due to its very smooth surface.

deo_pavel schrieb:
Can you get adhesion primer at hardware stores, or is it better to order online?

Usually, you can find adhesion primers for plastics in large hardware stores, typically in the paint section. Alternatively, they are available at specialist paint shops or through online platforms. Pay attention to product descriptions, especially those indicating "for smooth surfaces" or "for plastic." The adhesion primers should be compatible with acrylic paints to ensure the best adhesion.

For application: use a brush with clean, fine bristles or a foam brush to achieve an even coat.

I’m happy to answer more questions if you need further details.

PeoDaniel schrieb:
Generally, you can find adhesion primers for plastics in the paint section of large hardware stores.

Additionally: If you order the adhesion primer online, I can recommend products from the company "Rust-Oleum," which specifically offer primers for plastics. These are usually easy to apply and versatile.

Important for application are room temperature and humidity – ideally around 20°C (68°F) and dry, so that the primer and paint can fully cure. When sanding, you can also use edge sanders or sanding blocks to avoid damaging the edges of the KALLAX.

One more question for you: How pronounced are the stains caused by the water-based paint? Are they large discolorations or just small spots? That could influence the required pretreatment.

Nathanaelk schrieb:
How pronounced are the stains caused by the water-based paint?

The stains are quite large; the water-based paint has spread very unevenly in places, resulting in a noticeably blotchy appearance, especially along the edges and on horizontal surfaces. In some areas, the paint has also chipped slightly, exposing small spots of the white KALLAX underneath.

KAULIS schrieb:
A common mistake is applying the paint too thickly, which causes runs and stains.

Thanks, I'll keep that in mind, as that’s probably the reason it looks like this now.

I think I’ll follow your advice: sand the entire surface, wipe off the dust, apply an adhesion primer, and then repaint with good quality acrylic paint.

Should I use a brush or a roller? I’ve seen that there are special rollers available. Or is a brush better for small areas?