ᐅ My Kallax unit has uneven coloring after repainting – how can I fix the discoloration?

Hello everyone, I recently repainted my Kallax shelf to change its color. However, after the color change, some areas appear blotchy or show variations in color intensity, which is especially noticeable on the larger surfaces. It looks like the paint was applied unevenly or absorbed more in certain spots. I suspect it might be related to the surface or the preparation, but I’m unsure what to do about it specifically. What experiences have you had with color differences on Kallax units after repainting? What reliably helps to make the surfaces look even and clean again? Thanks in advance for your tips!

That sounds like uneven application or too thin a primer layer. It’s best to lightly sand the surface and apply a suitable primer for wood or MDF before repainting. This will ensure the paint is absorbed evenly.

Hey, patchy areas after changing paint colors are really annoying, but they mostly result from uneven removal of the old paint – basically an irregular surface texture. 🙂 Try using a good primer or bonding agent after sanding; this often smooths out the finish. And don’t apply it too thickly! Multiple thin coats are the key here.

ju_ren schrieb:
It’s best to lightly sand the surface first and apply a suitable primer for wood or MDF

Thanks for the tip! I had actually only removed the old paint but didn’t use any primer.

dijan schrieb:
Try using a good bonding agent after sanding

Is a bonding agent different from a primer, or can they be considered the same in this case? I’ve struggled a bit with the terminology and want to make sure I do it right.

Maybe you can also recommend if there are specific products that work especially well for MDF / Kallax and are easy to find?

I’m happy to help with a few clear steps so you can get your Kallax unit evenly painted again:

1. Preparation: Lightly sand the module to create a matte surface. This helps the paint adhere better.

2. Primer/Adhesion Promoter: In your case, primer and adhesion promoter are similar – primer fills pores and ensures even absorption, while adhesion promoter improves the bond between the substrate and the paint. For MDF, I recommend a combined primer/adhesion promoter, such as an acrylic universal primer.

3. Intermediate Sanding: After the primer has dried, lightly sand the surface again to smooth out minor imperfections.

4. Painting: Apply several thin coats (preferably with a brush or a paintable foam roller). Always allow each layer to dry thoroughly between coats.

5. Final Treatment: Optionally, you can use a clear coat as a protective layer; this also helps visually even out small color variations.

For MDF and Kallax, a water-based acrylic paint is often a good choice because it dries quickly and has less odor.

Stick with it, and you’ll achieve a clean, professional result!

Jensson schrieb:
apply several thin layers [...] Always allow each layer to dry thoroughly before applying the next.

So, does that mean it’s pointless to apply one thick layer just to cover the stains quickly?

One more question: I sometimes see people using spray cans or spray guns for applying paint. Would you recommend that for a Kallax module, or is it better to avoid that if you want an even surface?

I think I still had some room for improvement while applying the paint with a brush.