Wood Filler FAQs – Everything You Need To Know About Fillers

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A much-discussed topic about woodworking is wood filler and its uses. Although every woodworker uses this substance abundantly almost every day, there is a lot of ambiguity about its use. You will not find a wood filler that suits every requirement. It depends on a variety of factors, and even the most experienced woodworkers may falter a bit when it comes to wood filler.

In this post, we deal with some of the most commonly-asked questions about wood filler. We hope that the answers will help you to get the best out of it. Before we get into this rather interesting question and answer session, let’s first take a brief look at what wood filler is and why we use it.

Wood Filler – A Brief Outline

Minwax 42853000 Stainable Wood Filler, 16-Ounce
Stainable Wood Filler (Image: Amazon)

You need to repair the surface of wood that contains defects by using wood filler. Wood putty is also a type of wood filler, and we show you the difference between wood filler and wood putty in another interesting post. But we will touch upon wood putty here as well because it serves a similar function in woodworking.

Whether it is wood filler or wood putty, the primary function of this substance is to cover defects and flaws in wood. A lot depends on how you use them, and which particular type of filler you use.

Wood Filler FAQs

Let us dive straight into the commonly-asked questions about wood filler. While we may not be able to cover every possible question that gets asked, we will try to include the most common ones:

Q: How many types of wood fillers are there?

A: There is no definite number of wood fillers. However, the main two categories are water-based and solvent-based wood fillers. Then, we get latex and epoxy wood fillers as well. A type of wood filler that you can use outdoors is exterior wood filler and caulk. You can make your wood filler by mixing sawdust with wood glue.

Q: Can we sand and paint over all types of wood fillers?

A: Although you can sand over most types of wood fillers, a wood filler that can be painted over will be specified by the manufacturer. Hence, check with the manufacturer’s specifications or ensure in advance that the wood filler you buy can be painted over.

Q: Can we drive nails and screws into areas that contain wood filler?

A: Some types of wood filler will take nails and screws readily, and some may not. If you expect to use several nails and screws in your project that has its wood surface filled, latex wood filler is a suitable option.

Q: Can we get colored wood filler to match the color of the wood?

A: Yes, you can get wood filler in different colors and shades to match the color of the wood. Some manufacturers even produce clear wood filler which makes it easier to blend with the color of the wood.

Q: What is the difference between wood filler and wood putty?

A: Another name for wood putty is “plastic wood.” It consists of synthetic materials, and we apply it to the surface of wood after finishing or staining. It is softer than wood filler and appears like clay. Wood filler, however, is a combination of sawdust and wood shavings and we always apply it before finishing or painting the wood. We usually use wood filler if you need to fill larger holes and blemishes.

Q: How can we make homemade wood filler?

A: If you are unable to procure a wood filler of a suitable color, then homemade wood filler is your best option. You can prepare this type of wood filler by combining sawdust with lacquer to form a paste. Once the filler is ready, you can use it like any other wood filler.

The advantage of homemade wood filler is that you only need to prepare as much as required each time, and you can use the sawdust of your woodworking project to get a perfect color match. Sawdust mixed with wood glue also makes an excellent homemade wood filler.

Q: What is the most convenient packaging for using wood filler?

A: Wood filler in a tub is the most popular form of getting wood filler. Conveniently-sized tubs enable you to apply the wood filler to the job directly with the help of a putty knife or spatula. Ensure to close the lid of the tub tightly after use. Keep in mind that once opened, the contents have a limited shelf life.

Q: What are the suitable types of wood filler for outdoor use?

A: Ideally, you would use wood putty for outdoor projects. However, you can get wood filler suitable for outdoor use as well. You need to read the manufacturer’s specifications. Wood filler for outdoor use will have the information mentioned on the packaging.

Q: Does adding a wood filler to joints add to the structural strength?

A: No, wood filler seldom adds to the structural strength of wooden parts. However, an exception may be where you have used wood glue to make homemade wood filler. In such a case, the wood filler will act on a joint somewhat like the way a joint derives additional strength when wood glue is applied to it.

Q: What is the drying and curing time for wood filler?

A: Most wood fillers will take about 30 minutes to set, but we recommend that you wait for an hour before proceeding further. Typical curing time can range between 12 hours to 48 hours. It is always a good idea to look at the instructions on the packaging, as the recommended times may vary from one manufacturer to another. Atmospheric moisture and temperature also affect the time taken for wood filler to dry and cure.

Q: How do we maintain color consistency while painting or staining over wood filler?

A: The objective while painting or staining over wood filler is to make the defects in the wood invisible. If the background color is white, it is generally easy to cover over the filler by applying a matching shade. It is a bit more complicated when staining over a piece to which filler has been used.

You need to get the color of the stain to match or be darker than the color of the filler. A best practice is to use a test piece with some filler added. Once you get a suitable shade of stain, you can proceed to add it to the job.


Using wood filler is easy, but you need to know what you are doing. We get wood fillers of all imaginable types and brands. If you want to use wood filler effectively, you need to know which type to use and where to use it. We hope that by reading through this list of FAQs, you will get answers to most of the questions you may have.

If you have any further questions or concerns, please leave your comments in the section below, and we will get back to you.

Happy woodworking!