How Long Does Wood Filler Take To Dry: The Drying Process Explained

Unless we are practicing the old style of woodworking that does not use mechanical connection methods of nails and screws, we’re going to be making holes in our wood.

I marvel at the building methods of Japanese home construction that do not use any nails, screws, or other metal connecting/securing methods and the way in which joints are built in that style.

But we use nails, screws, brads, and other such items in our woodworking shop, and that leaves holes needing to be filled. Sometimes, too, it’s a repair job on a joint or to repair a dent or ding that leaves a hole of some kind.  

Enter fillers.  We all have them in our shop, whether wood filler, wood putty, or plastic wood.  When using them, it’s important to use the right filler for the right space and wood, just as it is important to understand drying times for each type of filler.  It results in a better fill and a more professional job.  

Today we want to talk about the drying process and how long to wait before continuing to work on the fill.

Key Points:

  • It depends:  solvent-based and oil-based wood fillers dry quicker than water-based wood fillers; wood putty dries but does not harden.
  • Some wood fillers dry as quickly as 30 minutes and are ready to sand, while others may take a couple of hours up to 6 hours.
  • The drying process can be sped up a bit by applying heat, applying the filler in warm temperatures, and adding a drying agent. We haven’t tried it yet, but warming in a microwave oven might also help speed up the drying process.

What Is a Wood Filler?

Wood filler is a substance used to fill imperfections in wood, such as nail holes, cracks, and dents. It is typically made of a mixture of wood fibers, sawdust and wood particles and wood byproducts, and a binder that hardens.

Wood filler is available in a variety of colors to match different types of wood.

The main types of wood fillers are water-based and solvent-based/oil-based. Water-based wood filler is easier to sand and is less likely to shrink, but it takes longer to dry.

Solvent-based wood filler dries more quickly, but it can be more difficult to sand – they are made from epoxy or vinyl. Oil-based fillers are made with – you guessed it – oil as the medium.

To use wood filler, first clean the area to be filled. Then, mix the wood filler according to the manufacturer’s instructions. Apply the wood filler to the area with a putty knife, making sure to fill the hole or crack completely. Once the wood filler has dried, sand it smooth and apply a finish.

Wood filler is a versatile product that can be used to repair a variety of damage to wood. It is a relatively inexpensive and easy-to-use product that can help you restore your wood to its original condition.

Here are some of the things you can use wood filler for:

  • Fill nail holes
  • Repair cracks and dents
  • Fill gaps between boards
  • Level uneven surfaces
  • Smooth out the grain of wood
  • Prepare wood for painting or staining

When choosing a wood filler, it is important to consider the type of wood you are working with, the size of the area to be filled, and the type of finish you will be applying.

It is also important to read the manufacturer’s instructions carefully to ensure that you are using the product correctly.

Here are some tips for using wood filler:

  • Apply the wood filler in thin layers. This will help to prevent the filler from shrinking and cracking.
  • Sand the wood filler smooth after it has dried. This will help to create a level and even surface.
  • Apply a finish to the wood filler to protect it from moisture and damage.

With a little care and attention, you can use wood filler to repair damage to wood and restore it to its original condition.

What Are Other Types of Wood Fillers?

There are many different types of wood filler available, each with its own advantages and disadvantages.

Here are some of the most common types:

  • Water-based wood filler: This is the most common type of wood filler best used for indoor applications. It is easy to use and sand, and it is less likely to shrink than solvent-based wood fillers. However, it takes longer to dry.
  • Solvent-based wood filler: This type of wood filler dries more quickly than water-based wood fillers, but it is more difficult to sand, and it can be more harmful to your health.
  • Epoxy resin wood filler: Epoxy wood filler is a two-part filler that is very strong and durable. It is a good choice for filling large gaps or repairing structural damage.
  • Polyurethane wood filler: Polyurethane wood filler is a water-based filler that is resistant to moisture and chemicals. It is a good choice for filling gaps in outdoor furniture or other projects that will be exposed to the elements.
  • Pore filler: Pore filler is a type of wood filler that is designed to fill the pores in wood. It is a good choice for filling gaps in unfinished wood or for preparing wood for staining.
  • Plastic wood filler: Plastic wood filler is a synthetic wood filler that is very strong and durable. It is a good choice for filling large gaps or repairing structural damage.

When choosing a wood filler, it is important to consider the type of wood you are working with, the size of the area to be filled, and the type of finish you will be applying.

It is also important to read the manufacturer’s instructions carefully to ensure that you are using the product correctly.

Why Does Water-Based Wood Filler Take Longer To Dry than Solvent-Based Wood Fillers?

Water-based wood filler takes longer to dry than solvent-based wood filler because water evaporates more slowly than solvents.

Water-based wood filler is made of a mixture of water, wood fibers, and a binder. When the water evaporates, the binder hardens, and the wood filler dries. Solvent-based wood filler is made of a mixture of solvent, wood fibers, and a binder. When the solvent evaporates, the binder hardens, and the wood filler dries.

Solvents are more volatile than water, which means that they evaporate more quickly. 

In addition, water-based wood filler is often thicker than solvent-based wood filler. This also contributes to the longer drying time of water-based wood filler.

The drying time of wood filler will be influenced by environmental factors like moisture levels and fluctuations in temperature.  Wood filler will dry more quickly in a warm, dry environment than in a cool, humid environment.

Here is a table summarizing the drying times of water-based and solvent-based wood filler:

Type of Wood FillerDry Time
Water-based30 minutes to 2 hours
Solvent-based15 minutes to 1 hour

The actual drying time may vary depending on the brand of wood filler, the amount of wood filler used, and the environmental conditions.

When choosing a wood filler, it is important to consider the drying time. If you are in a hurry, solvent-based wood filler is the better choice. However, if you are not in a hurry, water-based wood filler is a good option.

Water-based wood filler is also easier to sand than solvent-based wood filler.

How About Wood Putty As A Filler?

Wood Putty

Wood putty is an oil-based wood filler that is also used to fill small holes and cracks, but differs from wood filler in that it should be used in finished wood rather than unfinished wood.

It is typically made of a mixture of wood fibers, sawdust, and a binder that does not harden. This makes it pliable and easy to work with, even on curved surfaces. Wood putty is also available in a variety of colors to match different types of wood.

Minwax Wood Putty, an oil-based wood putty,  comes in colors that match Minwax Wood Stains, for instance. Oil-based putty is the right choice for an outdoor use.

Wood putty should be used when you need to fill a small hole or crack in finished wood that will not be sanded or stained. The ability to use a putty that matches the extant wood finish is certainly a great convenience.

It is also a good choice for filling cracks and holes in exterior wood that will be exposed to the elements.

Oil-based wood putty is the more frequently used type of putty, especially on outdoor projects, because it is more resistant to the elements.  

Here are some of the things you can use wood putty for:

  • Fill nail holes
  • Repair cracks and dents
  • Fill gaps between boards
  • Level uneven wood surfaces
  • Smooth out the grain of wood

Here are some of the situations where you should not use wood putty:

  • To fill large holes or cracks
  • To fill holes in unfinished wood
  • To fill holes that will be sanded or stained

If you need to fill a large hole or crack, you should use a wood filler that hardens. If you are filling a hole in unfinished wood, you should use a wood filler that is compatible with the type of finish you will be applying.

If you are filling a hole that will be sanded or stained, you should use a wood filler that can be sanded and stained.

Here are some tips for using wood putty:

  • Choose a wood putty that is the same color as the wood you are working with.
  • Apply the wood putty in thin layers. 
  • Apply a finish to the wood putty to protect it from moisture and damage.

How Can The Drying Process of Wood Filler Be Sped Up?

There are a few ways to speed up the drying time of wood filler. Here are a few tips:

  • Use a solvent-based wood filler. Solvent-based wood fillers dry more quickly than water-based wood fillers.
  • Apply in thin layers. The thicker the application, the longer the drying time.
  • Work in a warm, dry environment. Wood filler will dry more quickly in a warm, dry environment than in a cool, humid environment.
  • Use a heat gun or hair dryer. A heat gun or hair dryer can be used to speed up the drying time of wood filler. Be careful not to overheat the wood filler, as this can damage it.
  • Use a drying agent. A drying agent is a chemical that can be added to wood filler to speed up the drying time. Be sure to follow the manufacturer’s instructions when using a drying agent.

It is important to note that speeding up the drying time of wood filler can sometimes affect the quality of the finished product.

For example, wood filler that is dried too quickly may be more likely to crack or shrink. It is important to experiment with different methods to find the one that works best for you.

Here are some safety tips to keep in mind when using wood filler:

  • Always wear gloves and a dust mask when working with wood filler.
  • Be careful not to get wood filler in your eyes. If this happens, flush your eyes immediately with water for 15 minutes and seek medical attention.
  • Do not use wood filler near an open flame or heat source.
  • Store wood filler in a cool, dry place.

Which Is Better For Outdoor Projects – Filler or Putty?

We now know the differences between wood filler and wood putty, but which is better for outdoor use?

Wood putty is the better choice for any outdoor use. Wood putty is a pliable material that does not harden, so it can expand and contract with the wood as it is exposed to the elements.

Wood filler, on the other hand, hardens and can crack or shrink when exposed to moisture and temperature changes.

Here is a table summarizing the pros and cons of wood filler and wood putty for outdoor use:

MaterialProsCons
Wood fillerEasy to use, sandable, and stainable. Intended for use on unfinished woodCan crack or shrink when exposed to high humidity levels and temperature changes
Oil-Based Wood puttyPliable, does not harden, and can expand and contract with the wood. Comes in a variety of colors to match finished woodDoes not sand well because it does not harden 

If you are filling a small hole or crack in outdoor wood, then an oil-based wood putty is a good option. If you are filling a large hole or crack, then you may need to use a wood filler that is specifically designed for outdoor use.

Making Your Own Filler

We’ve written about making your own wood filler in past articles.

In fact, we wrote about two ways to make your own:  making wood filler without sawdust and a beginner’s guide to using wood filler that includes a recipe for making wood filler with sawdust.

Again, remember that wood filler is for use on unfinished woods and interior applications.  These recipes are easy to make and can do well when you have run out of commercial products.  They work well, harden, and are sandable

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