when to sand wood filler?

There is a lot of conflicting information out there when it comes to how to work with wood filler. I’ve seen articles that say you need to sand wood filler before painting, while others say you don’t.

Some people say that you need to use putty before working with wood filler, while others insist that sanding is all you need.

It can get confusing! In this article, I’m going to lay out all the facts so that you can make an informed decision about whether or not to sand wood filler and what tools are best for getting the job done right.

Do you have to sand wood filler before painting?

Yes, you do. Sanding wood filler is a necessary step before paismoothly You need to sand it smooth and level so that the top coat will stick to it.

You can use either a power sander or a hand sander for this purpose. The key is to get all of the bumps out before you paint, so you won’t have any bulges after the paint dries.

How do I get a smooth finish with wood filler?

Once the wood filler has dried, use a sanding sponge to smooth it out. To keep your work surface from getting damaged, cover it with plastic wrap first.

Use light to medium pressure when sanding and avoid applying too much pressure at once. This will help prevent gouges or deep scratches in the wood as you go.

As you’re smoothing out the filler, be sure not to leave any rough patches or uneven surfaces that could show through after painting or staining (be sure to get all of those spots). For extra smoothness, finish with fine grit sandpaper in the same direction as your grain of wood.

Do you use wood putty before sanding?

Wood putty is a type of filler that can be used to fill in cracks and holes on wood surfaces. It can also be applied to a bare wood surface, but it’s more likely to crack if you leave it unpainted.

When using wood putty, keep a few things in mind:

  • Wood putty should always be sanded after painting. It’s not necessary to sand it before painting, but doing so will help smooth out any rough edges or drips.
  • If your project requires multiple layers of paint (for example, if you’re painting over an existing painted finish), then make sure that each layer dries completely before applying the next one! This will prevent any peeling or cracking down the line when all those coats start blending together with age/humidity changes…which leads me nicely to my next point…

How many coats of wood filler do I need?

For small holes, one coat of wood filler is enough. If a hole is larger than two square inches and you want to cover it with wood filler, then two coats are needed.

For large gaps (for example, between the kitchen and living room), three layers of wood filler are recommended if you want the gap to be filled completely.

Why is wood filler showing through paint?

Wood filler is a solid material that comes in a variety of textures, from coarse-grain to fine-grain. The finer the grain, the more sanding it will require to achieve a smooth finish.

If you do not sand your wood filler to a smooth finish, it will show through paint when applied over the top of it.

Can you wet sand wood filler?

  • Yes, but it’s not as effective. The process of wet sanding a wood filler is similar to dry sanding except that water is used instead of dry paper. As with all things, there are pros and cons to this method.
  • Pros: If you’re in a hurry, wet sanding will save time because you can use finer grits than if you were dry sanding. The water helps float out the particles, which means they won’t scratch your project when they come loose!
  • Cons: There are some disadvantages to using water during your project—it can damage the wood filler if too much pressure is applied during the process or if too much moisture gets into the surface of the wood after it dries (especially on humid days).

How thick can wood filler be applied?

The thickness of the wood filler is ultimately up to you, but it’s worth knowing that the thicker it is, the more sanding will be required before it’s smooth enough to paint over.

If you’re working on a large project like an armoire or dresser, you may need to apply more than one coat to get the desired thickness.

You’ll want to let your wood filler cure for at least 24 hours before sanding it down with 120-grit sandpaper (or higher).

How do you make wood filler look like wood grain?

  • Use a wood filler with a grain, such as spackling paste.
  • Sand the filler until it matches the wood’s surface. You can use either fine sandpaper or a power sander to achieve this result, although you’ll need to do so before painting over it because most paints are thicker than wood filler and will not adhere properly if applied directly to the filler.


The bottom line is that you should sand wood filler before painting. If you’re trying to fill in a large hole, it’s best to do so with two coats of wood filler instead of one thick coat.

You can also use an orbital sander for a smoother finish if needed. As always, we hope this article helps you out with your next project!

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Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

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