Sanding MDF doesn’t require a great deal of preparation before you paint but after you get that first coat on and if you want to create fantastic looking and long-lasting MDF furniture, you need to sand your MDF board before applying that second coat.
Before you start applying a primer or first coat, you prepare the MDF with a light sanding. Try using a around 120 grit sanding sheet.
The first coat of paint once dried is slightly gritty but this is easily smoothed with light sanding..Sanding MDF will allow the primer and paint to sit well on the surface.
ATTENTION WHEN SANDING MDF
When you start sanding please make sure the room you use is fully ventilated and you should make sure that you wear eye protection, such as goggles and a face mask.
Make sure that after you have sanded the surface you clear all of the dust away. If any loose dust particles are left behind, it can affect the application of the paint, so keep the area clean.
USING A SANDING BLOCK
Many people don’t use sanding blocks when sanding. They tend to grab the sand paper and off they go. Tradesmen are the worst offenders because they need the job done as quick as possible and grab the nearest piece of sandpaper to get the job done. The fact is the reason we sand is to (usually) try and get the surface as flat and smooth as possible so using a sanding block is a must have.. Your hand will never be 100% flat on the surface of the MDF so the MDF won’t become equal in smoothness.
I like to use good quality, very fine sandpaper like 220 or 240 grit. MDF doesn’t have directional wood grain so you can sand in any direction. Only apply light pressure when sanding MDF. Try
THE FINISHED VERSION
Here are a few plaques that have been sanded and prepared with paint. You can clearly see the professional finish to them and this would not have happened if we had not sanded in between coats.
check out our full video on 5 Things You Must Do When Working with MDF