How to Make Wood Filler from Sawdust

Homemade wood filler is versatile and cost effective. Making your own wood filler gives you complete control of the process and provides more predictable outcomes. You can save yourself money and produce a better quality outcome if you make and use your own wood filler from sawdust.

Wood filler comes in handy for a wide variety of DIY projects. It can be used to patch nail holes, screw holes, and to level out dips and indentations in wood. There are only two common ingredients in homemade wood filler: wood glue and sawdust.

We will explore scalable recipes and tips and tricks for creating homemade wood filler in bulk.

Mixing Tools Used to Make Wood Filler from Sawdust

To create homemade wood filler, I recommend finding an appropriately sized mixing container.

  • If you are looking to whip up a small batch, a disposable plastic cup will do the job.
  • For larger batches, consider a large, plastic mixing bowl or clean five gallon bucket.

The batch size will determine your mixing equipment.

  • If you are mixing a small patch, a simple popsicle will do the trick.
  • For large batches, you may want to try a paddle mixer attached to a power drill.

Selecting Wood Glues for Creating Wood Filler from Sawdust

There are a variety of wood glues on the market. Determining which glue is best for you depends on the application. When you go into your local home improvement store, it is likely that you will see five types of wood glue.

three wood glue on the top of wood plank

The bonding agents are what separate the various types of wood glues. The key five different bonding agents I will discuss are PVA, polyurethane, CA (or superglue), epoxy resin, and hide glue.

PVA or Polyvinyl Acetate Wood Glue

PVA glue has excellent flexibility but does not accept wood stain well. If you try to use this glue for your wood filler, you will only have one shot. The glue dries quickly and will not store well once mixed.

There are different formulations of PVA, some intended for indoor and others for outdoor use. The outdoor formulations are normally yellow in color while indoor PVA is often white.

This is not my top choice for creating a wood filler. If you do go with a PVA glue, double-check that your chosen formulation matches the final location of your filler.

While it is possible to stain over wood glue, it is not recommended if you don’t have to.

Polyurethane Wood Glue

Polyurethane is an extremely common binder in wood glues. It penetrates wood pores and forms strong linkages of chemical bonds between pieces of wood. 

Polyurethane, however, inhibits wood stain from effectively augmenting the coloration of the wood on which it is applied. The same wood pores that wood stain needs to penetrate to affect color will already be filled by polyurethane.

Polyurethane-based wood glue can be a good choice if the piece you are filling will not be stained afterwards.

CA or Cyanoacrylate or Superglue

Do not use this CA wood glue for your wood filler. It dries nearly instantly and is very pretty. The bonding agents do not flex and your filler will be unworkable almost instantly.

Super glue has many great uses but mixing with sawdust to create wood filler is not one of them. Avoid using cyanoacrylate for this project. 

Epoxy Resin

Epoxy resins are some of the highest rated wood bonding agents in the world. It is the go to type of wood glue for many woodworking professionals. However, mixing epoxy resin with sawdust would defeat the purpose of homemade wood filler.

Epoxy resin will not accept wood stain and will stand out like a sore thumb. The high upsides of homemade wood filler are its low cost and how well it blends into the wood into which it is applied. Epoxy resin is both expensive and must be painted.

Hide Glue

This is a traditional glue that works well for making homemade wood filler. This is the type of wood glue I recommend for making homemade wood filler.

There are two subtypes of wood glue: crystalized and liquid. I recommend using the liquid hide glue to make wood filler. 

Liquid hide glue remains in its liquid state long enough to be mixed well with sawdust. The wood filler you create will also remain pliable if placed in an airtight container. The top layer may harden if an air gap exists within the container, but below the hardened cap, the wood filler should still be usable.

Choosing Sawdust for Your Wood Filler

In nearly every instance in which you create your own wood filler, you will want to match the wood species of your sawdust to the species of your project to be filled. If you are working to create a project that will need wood filler, save sawdust as you cut and join pieces.

After matching species of wood, the next most important trait of the sawdust is its fineness. The finer the sawdust, the better it will work as a wood filler.

Within homemade wood filler made from sawdust, the sawdust’s primary function is to add color-matching properties to the wood filler. Finer sawdust will result in more consistent coloration and improve the aesthetic outcome of the sawdust wood filler.

Some of the best places to get your hands on sawdust for projects like this are from sawdust collection bags attached to sanders. 

Tools:

  • Sander with collector bag
  • Clamps
  • Secure working surface 

Method:

  1. Determine the species of wood from which you need sawdust.
  2. Find scrap wood from a matching species of wood.
  3. Use clamps to secure selected wood to a work surface.
  4. Sand wood using rough grit sandpaper until you have collected the necessary amount of sawdust.

Tip: Save the sawdust from your smaller woodworking project. When working on an oak project, save the sawdust in an airtight container labeled “oak.” This will make matching project species and sawdust species for homemade wood filler easier.

If  you do not have time to create your own sawdust, sawdust can sometimes be received for free from local carpentry shops. Some home improvement stores also carry sawdust as floor sweep. A few phone calls can gain you all the sawdust you need to complete this project.

Creating Wood Filler from Sawdust

Now that you have determined the best tools, wood glue, and sawdust for the job, it is time to create the wood filler.

Tools Needed:

  • Mixing vessel
  • Stirring tool
  • Sawdust
  • Wood glue

Method:

  1. Make sure your mixing vessel and stirring tool are both clean and free of dirt, grime, and contaminants.
  2. Put sawdust into your mixing vessel.
  3. Add liquid wood glue to the sawdust. Begin with a 10:1 ration (10 parts sawdust to 1 part wood glue).
  4. Work the glue through the sawdust by stirring.
  5. Continue adding wood glue to the sawdust-glue mixture until you achieve a putty-like consistency.
  6. When you have the appropriate consistency, apply the wood filler to the project using a putty knife. Slightly overfill the holes, gaps, cracks, and depressions.
  7. Put all remaining wood filler in an airtight container for future use. The amount of air the wood filler is exposed to will determine its viability for future use.
  8. Clean all vessels and mixing tools using hot water and a scrub brush.
How to Apply Wood Filler to Fill Nail Holes

Conclusion

A combination of sawdust and wood glue can be a craftsman’s best friend. This simple wood filler usually requires around a three-to-one ratio of sawdust to wood glue. This ratio may vary depending on the area of application and needed viscosity. After mixing, this homemade wood filler can be easily applied. It can help form bonds within the wood and can usually accept wood stain.

An expert at home repair, remodel, and DIY projects for nearly 40 years. His first experience came in completely restoring an antique home. Completely redone from the inside out, and restored to its original form, the home is a featured design by renowned Southern California Architect Cliff May, considered to be the father of the California Ranch Home. Now Dennis spends his time on fine woodworking projects and tool comparisons.