How to Prep Wood for Paint the Right Way: Scraping, Sanding, and Priming Tips

When you’re painting wood, the time you put in preparing the surface can be more impactful than the actual painting. If you don’t prepare the wood correctly by sanding, scraping, and priming as needed, your paint may not adhere or may wear off quickly. Any imperfections you don’t deal with before painting will show through in the final job.

This article will outline the key steps for how to prep wood for paint, whether you’re starting with bare wood or redoing a previously painted project. 

Investing time in learning how to prepare a wood surface for painting sets it up for a smooth, professional finish that will last for decades. Skipping this step can lead to costly do-overs down the line, including peeling paint and uneven coverage.

Paint performs best when it’s applied to clean, smooth, bare wood. Old paint, dust, dirt, and oils all interfere with paint adherence.

If a contractor applies paint to pressure-washed wood that wasn’t allowed to dry completely, they’re likely to see bubbling within days of finishing. If they paint without stripping oils, the freshly applied paint will start peeling off soon after it dries.

Having the right tools is critical for surface prep. You’ll need tools such as scrapers and putty knives to remove peeling paint or old adhesives and fix any defects to prepare wood before painting. Hyde Tools offers ergonomic scrapers that make the job easier on your hands.

Sanding blocks and sponges will provide a smooth surface for the primer or paint. Vacuums and tack cloths remove dust so you don’t have flecks of it in your paint. Sanding generates a lot of dust and debris that can be a health hazard. Hyde Tools’ dust-free sanding system is trusted by professionals to reduce their exposure to harmful sanding debris and deliver better results.

Primers seal the wood and prepare it for paint. Depending on the job, you may be able to use an all-in-one primer rather than two separate products, but you’ll still need to prepare the surface properly. 

The following guide will outline exactly how to prep wood before painting. If you follow all of these steps, you should end up with professional results that will last.

Before you begin, check your wood’s condition. Look for any signs of rot by checking for soft spots. Use a screwdriver to probe gently. If you find any soft spots, remove them.

Check for signs of water damage. You can repair small spots of mold or water damage, but if it’s extensive, you may need to replace the wood. Secure any loose boards or nails before you begin.

If your wood was previously painted, you’ll need to remove the old paint. Use manual scrapers to take off any peeling or loose paint. A heat gun can help you remove multiple layers of paint. Use it in a well-ventilated area and keep the gun moving to avoid scorching the wood. You can use gel-based strippers if heat or abrasion will damage delicate wood. Make sure you use personal protective equipment, such as gloves and respirators. 

After you check the wood and remove the paint, you need to clean it. You can use mild soap and water if the surface isn’t too dirty. If you need to cut through grease and gloss, you can use trisodium phosphate. Scrub the wood with a stiff nylon brush dipped in the cleaner. Go in the direction of the grain.

Rinse with clean water and allow the wood to dry completely. This can take 24 to 48 hours, depending on the humidity level.

There are many types of abrasives you can use on your painting project at different times. Sanding smooths the surface to prep wood for painting.

Sandpaper is labeled based on the grit size. Larger grit, such as 120, removes surface irregularities and can feather out the edges of existing paint. Follow this with finer grits in the 180 to 220 range to refine the surface for priming.

As with cleaning, sand with the grain to prevent scratches that can show through in the finished product.

If you removed any soft spots or there are any cracks or surface damage, repair with wood putty or spackle. The best type of spackle or wood putty will depend on the project.

For interior woodwork, use a water-based filler because it sands more easily and is low-odor. If you’re working on an exterior project, you’ll have better results with a solvent-based filler or a two-part epoxy filler.

Apply the filler with a putty knife, overfilling slightly so you can sand it down. Once it’s dry, sand it down so it’s even with the wood. You may need to do this several times if you’re fixing deep damage.

Priming your wood ensures the paint has a uniform surface to stick to and blocks any stains from showing through. Water-based primers dry quickly and are easier to work with. Oil-based primers provide better coverage and are more durable, so they’re usually a good choice in exterior or high-traffic areas. Bonding primers work well if you’re trying to cover a glossy surface.

After you apply the primer, let it dry completely according to the instructions. Sand it down with a fine-grit sandpaper for an extremely smooth base. Now, you’re ready to start painting.

Prep work can be the toughest part of painting wood. However, if you take the time to do it right, it will pay off in the end.

Investing in quality tools from Hyde Tools makes the job faster and easier and helps you deliver professional results with clean paint edges. Check out our entire line of paint and sanding products, including different types of paint brushes and other pro-grade tools.