Can You Stain Over Wood Filler? (How-To)

Wood filler helps fill and cover nail holes, cracks, lines, and gouges in the wood. It’s your go-to product for repairs. But can you stain wood filler?

You can stain over stainable wood filler. They are a new product designed to absorb stains as natural wood does. It comes uncolored.

On the other hand, unstainable fillers don’t accept stains very well. The color will not set properly over them. They often come pre-colored, usually with white color. 

Is Wood Filler Stainable?

Wood filler doesn’t absorb stains well because it is designed to fill and cover holes and cracks. As a result, it is designed to be as compact or tight as possible so it can cover and fill spaces.

In simple words, the wood-filling compound isn’t porous. This makes it difficult to absorb stains properly. So, if you do it, the area will appear darker and tacky because the stain can’t penetrate it as it should. 

So, the stain will stay over the filling compound, and turn sticky (remain semi-solid). At this stage, the stain will be too thick to allow light to pass through making the area appear darker than the rest of the surface.

The filling compound also makes the surface appear darker because it comes pre-colored. Though its color is neutral, it still prevents the wood grain from showing. Wood stain however is usually designed to reveal the grain. So, applying it over a wood filler means the grain will be covered making the spot appear darker.

However, the stainable wood filler will absorb stain. They are made from porous materials, including sawdust which makes it possible for these wood fillers to absorb stain. You can also make your own stainable filler by mixing sawdust with a binding agent like glue.

Can You Stain Plastic Wood Filler?

You can stain over plastic wood fillers as they are 70% porous in terms of composition. Since they are gotten from wood, they will absorb stain.

Plastic filler is made from wood dust and a binder. It is a combination of fine dust or blended wood and glue. This means plastic filler is more porous than regular or epoxy filler.

However, it doesn’t accept stains as natural wood does. While plastic wood filler is made from 70% wood, the remaining 30% is glue and additives.

The 30% glue and additives formula prevents it to accept stains like 100% wood furniture does. If you stain over it, there will be differences in the shade or color of the finish.

Also, you have to stir the plastic filler before applying it as it solidifies inside the can and in that state, it will be difficult to apply it without stirring first. You might even need to thin it.

How To Stain Over Wood Filler?

Before we go on, you should remember that you can only stain over stainable filler. If the filler isn’t stainable, the finish will not come out well.

Here are some fillers that can be stained:

• Minwax Wood Filler
• Plastic Wood Filler
• Goodfilla Wood Filler
• Latex Wood Filler

Here are the tools you need:

• Fine-grit sandpaper
• Clean rags
• A wood stain
• A paintbrush or spray gun

1. Sand & Clean The Filler

Sand the filler to create tiny ridges and scars that the stain can seep into. Sanding also helps smoothens it so the finish can come out smoother. To sand it, use fine-grit sandpaper. After sanding, remove the dust and clean the surface.

2. Apply The Wood Stain

To apply stain, use a paintbrush or sprayer. However, a sprayer will offer better coverage and help the stain penetrate a surface better. 

3. Wipe Off The Excess Stain

After 30 minutes, wipe off the excess stain over the surface. If you don’t wipe it off, the finish will turn sticky and appear darker. 

4. Leave The Stain To Dry

On average, water-based stains take 1 hour to dry and less than a day to fully cure. Oil-based stains take longer to dry and can take over 3 days to cure.

The stain needs to fully dry before you clean it.  You can also seal it with a top coat or a sealant to make it more durable.

How to Hide Wood Filler after Staining?

Wood filler shows after staining because stains are designed to be a bit transparent. That’s because they are designed to show the wood grain once they dry. So, if you use them over a filling compound, the filler will show.

However, using a few methods, you can prevent it from showing:

1. Use Solid Stain

Solid stains are thicker than regular stains. They have more paint pigment and color so the finish is usually more vibrant. As such, the wood filler won’t show beneath its vibrant color.

Solid stains don’t need to penetrate as deep so they will stick better. But, if you use a solid stain, it’s not just the filler that won’t show, the wood grain wouldn’t show as well.

2. You Can Use a Deep Color

To prevent the wood filler from showing, use a dark color. Dark stain color will hide it from showing, but it will also hide the wood grain. You can also paint over the stain to hide the filler. 

These methods will only prevent it from showing if you use them before applying it.

How To Fix Wood Filler Showing After Staining?

1. Use a Sealant

Using a sealant or top coat can prevent the filling compound from showing. However, only use a colored sealant. Clear coats like water-based polyurethane will not cover it properly.

2. Apply Wood Glaze

A wood glaze will cover the filling compound and make the finish glossy.

3. Remove The Stain

The last resort is to strip the finish and start all over again. This is often the best alternative if you want the grain to show through the finish as other methods will cover the stain, the filler, and hide the grain.

FAQ’s

Does Wood Filler Stain The Same as Wood?

Wood filler doesn’t stain the same as natural wood. Due to its compact nature, the regular epoxy filler doesn’t allow a coating to penetrate properly. Even stainable fillers are designed to absorb liquid, they don’t stain as well as natural wood because they are not made from 100% wood.

The filler is designed to seal, cover, and fill damages in the surface. The product is designed to fill spaces and not absorb stains. So regardless of the advertisement and branding, the filler will not stain as good.

Types of Stain To Use?

It’s recommended to use a water-based stain over a filling compound. The water-based stain is thinner and is more likely to penetrate a filling compound. 

What If Wood Filler Won’t Stain?

If filler won’t stain, it means it’s an unsustainable filler. However, you can try to sand it to increase its absorption rate. 

Final Words

In summary, you can stain over stainable wood filler, but if the filler is labeled as “unstainable” you shouldn’t try to stain it. To increase the absorption rate, you should sand the surface.