Medium-thickness fiberboard, or MDF, is a structure part utilized for such countless things in the home: kitchen cupboards, washroom vanities, shelves, baseboards, inside entryways, end tables—the rundown goes on. With such countless pieces made of MDF, it follows that they will ultimately wear out and become chipped, dirty, or just dated-looking.
Luckily, you can paint MDF and resurrect these pieces. You can even form new cupboards, racks, and furniture from MDF and paint them—bringing about a smooth, glass-like completion.
Prior to You Begin
With its permeable surface and flaky edges, MDF may not appear to be a decent possibility for an effective paint work. The facts really confirm that paint applied straightforwardly to MDF can make the surface become swollen and mutilated. Edges direct up paint, regardless of how much paint you apply.
In any case, by treating the MDF with conditioner items first, you can paint MDF very much like you would other, less-permeable surfaces.
The enormous, level surfaces of MDF are simpler to paint than the edges on the grounds that the compacted wood strands structure a more tight bond across the surface. It needs less fixing. Furthermore, you shouldn’t experience enormous pits on a superficial level.
Utilize a one-venture clear sanding sealer to condition the MDF prior to painting. Oil-based sanding sealers function admirably, yet you can likewise utilize a water-based sanding sealer in the event that you like.
The edges of MDF can be molded with the equivalent sanding sealer as you utilized for the surfaces. Since the edges are so permeable, you’ll in any case need to apply different layers of sanding sealer and sand between each coat.
A superior strategy is to fill the edges with an acrylic polymer-based filler. This filler requires just a couple of uses and it deals with the enormous pits that you now and then experience in MDF edges.
Continuously work in an all around ventilated region when utilizing paints, fillers, or coatings. Wear latex gloves. While sanding, utilize breathing security.
Equipment / Tools
- Roller and foam roller covers
- Putty knife
- Sanding block
- Tack cloth
- Sanding sealer
- Polymer-based filler
- Paint tray and liners
- Sand Surface and Edges
- Apply Sanding Sealer
- Sand Surface
- Clean MDF Surface
- Apply Second Coat of Sealer
- Sand Second Coat of Sealer
- Apply Filler to Edges
- Sand and Apply Second Filler Coat
- Final Sanding
- Paint MDF
Sand Surface and Edges
With #220 grit sandpaper on a sanding block, lightly sand the surface. If the 90-degree edges are bumpy or flaky, carefully sand those down as well. Your goal is to remove any wax coating and knock down any high spots or other anomalies rather than to achieve a smooth surface. Sanding uncoated MDF too hard will abrade it and make it more difficult to seal and paint.
Apply Sanding Sealer
Stir the sanding sealer to mix. Pour the product into a lined paint tray. Roll the product onto the surface.
Let the sanding sealer dry for at least one hour. The sanding sealer likely has raised the surface of the MDF. With #220 grit sandpaper on the oscillating sander, sand the surface of the MDF smooth. Be careful not to sand through the sanding sealer.
Clean MDF Surface
Clean off the surface of the MDF first with a shop vacuum, then with a tack cloth.
Apply Second Coat of Sealer
Roll on the second coat of sanding sealer, just as you did with the first coat.
Sand Second Coat of Sealer
After letting the second coat of sealer dry for at least one hour, sand the surface a second time. Since the surface should not be raised any longer, you should be able to switch to the finer grit #320 sandpaper.
Apply Filler to Edges
With the putty knife, apply the filler to the edges of the MDF. Press the filler deeply into the holes and cracks. Let dry for two to three hours.
Another way to apply filler to MDF edges is to rub it on with a finger. This application method is messier, so you’ll need to do more sanding of the MDF to get rid of ridges.
Sand and Apply Second Filler Coat
By hand, lightly sand the edges of the MDF with #220 sandpaper. Wipe down with a dry cloth. Add a second coat of filler. Let this second coat of filler dry longer—about four hours.
Sand the second coat of edge filler with #320 grit sandpaper. Move the sandpaper to the surface of the MDF again and sand that, as well. Pay special attention to the 90-degree angle between the edge and the surface.
Wipe down the MDF with a tack cloth. Apply paint to the MDF by rolling, brushing, or spraying. Allow for about an hour between recoats. Recoat two or three times, if needed.
Tips For Painting MDF
- When applying edge filler, you can round the edges if you wish. Simply bulk up the filler to about 1/4 inch, then sculpt it to a rounded contour by hand with sandpaper.
- Sanding sealer and polymer filler soak up paint at slightly different rates. To equalize, apply a thin layer of primer to the edges before painting.
- Avoid using drywall compound as an edge filler. Use only a polymer-enhanced product for greater strength.
- Sealed and filled MDF cannot be stained. It can only be painted.