Matt is a professional painter who owns and operates his own painting business, specializing in interior and exterior house painting.
Do You Have to Sand Cabinets Before Painting?
So you've finished cleaning your cabinet doors and now you're ready to sand them, but maybe you're wondering if it's possible to safely paint kitchen cabinets without sanding them at all. There is a debate among painters and DIYers whether or not cabinets should be sanded before painting. One crowd says, yes, cabinets should always be sanded and the other crowd argues you can simply use liquid sandpaper (deglosser) instead.
Whether you decide to sand your cabinets is your choice, but I always sand before priming and painting, and there are good reasons to do so. I strongly recommend sanding before you paint.
Here's seven solid reasons to sand cabinets before painting:
- Stronger primer and paint adhesion
- Achieves a smoother finish
- Removes defects and roughness from raised wood grain
- Smooths out wood filler repair patches
- Bypasses exposure to deglosser chemicals
- Faster than scrubbing and rinsing deglosser
- Helps prevent chemical residue streaks and fish-eye in paint
The most important reason to sand your cabinets is to maximize paint adhesion. The surface of a stained cabinet door is usually very smooth and glossy. Priming and painting over a slick surface without sanding can cause the paint to rub off or chip easily. Sanding, especially mechanical sanding, dulls gloss and produces tiny grooves on the surface of the wood that paint grabs onto to form a stronger bond.
Another important reason to be sanding cabinets for painting is it achieves a smoother finish when you sand between each coat. Whether you're spraying the paint, or using a brush alone, airborne debris and dust particles get stuck in wet paint, but sanding between coats removes those defects. If your cabinets are oak and you're applying grain filler then you'll definitely have to sand to remove excess filler and smooth out the surface.
Does Chemical Deglosser Work as Good as Sandpaper?
I have experimented with various chemical deglossers, but I have yet to find a product to take the place of my sandpaper. Like I explained earlier, the friction from sanding creates tiny grooves on the surface to improve paint adhesion, unlike chemical deglosser.
I also find mechanical sanding with my orbital sander and pads to be a lot faster than scrubbing and rinsing off chemicals. Nobody likes sanding, but the process is a lot easier when the appropriate sandpaper grit is used. Using the wrong grit can extend sanding time or even permanently damage the wood. I cover some common mistakes in this article and the appropriate grits to use.
Sanding Cabinets for Painting
The biggest mistake people make when sanding and painting cabinets is using the wrong sandpaper grit before the first coat of primer and between coats of paint. Using super abrasive sandpaper is totally unnecessary and can do more harm than good, especially if you're sanding with an orbital sander. Coarse sandpaper can ruin door edges and leave scratches and gouges that show up in paint.
The Best Sandpaper Grit for Cabinets
Aggressively sanding down to the bare wood is unnecessary and can actually backfire if it's oak because it exposes more of the grain and tannin underneath. Don't damage your cabinets or complicate the process using the wrong grit.
The objective of the first sanding is to simply dull the gloss and create a paintable surface for a stronger paint bond. The best grit for sanding before primer and paint is 150 to 220, but my personal favorite is 220-grit. Use a finer grit of 320 to 420 between coats of primer and paint, or if you're sanding cabinets that are already painted. Do not use sandpaper coarser than 320 on painted cabinets.
For the first sanding, I sand cabinet doors and frames with an orbital sander, using 5-inch discs of 220-grit sandpaper. I only use my electric sander before priming and painting, not after. An orbital sander is the best way to sand cabinets quickly. I prefer 220-grit for the first sanding because it's coarse enough to dull surface gloss without causing damage or grinding down to the bare wood.
Use Sanding Pads Between Coats
I use the 3M Softback Sanding Pads (Fine Grit) to sand tiny grooves on cabinets and other areas too small for my bulky orbital sander to reach. I highly recommend the 3M Softback pads instead of using a folded sheet of sandpaper or sponges. These pads have made my surface preparation a lot easier. I also use them between coats and also for sanding grain filler. I can get repeated uses out of them before I toss them out.
The fine grit is equivalent to 320 to 420, according to 3M. They're closer to 220-grit when brand new, but become 320 after sanding a few doors. These pads last longer than the sponges I used before. They're also awesome for sanding and painting staircase spindles because they fold easily without tearing like sandpaper does. The fine grit is perfect for sanding between coats of primer and paint and won't leave any visible scratches. Lightly sand between your top coats.
Always Sand After Cleaning, Not Before
Wiping down sanded cabinets with chemical cleaners can lead to potential contamination and fish-eye problems if the cleaner becomes trapped inside the open pores of the wood. This really depends on the type of cleaner you're using too, but a safe bet is to simply clean and rinse everything before sanding.
If you're filling the grain too, always clean first otherwise the cleaner and water from rinsing will dilute the filler and wash it out of the grain. Another good reason to never sand before cleaning is because doing so will spread grease and other contaminants to other parts of the doors or even force them into the grain of the wood.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2022 Matt G.