Ever wondered if you can actually screw into wood filler without turning your project into a DIY disaster? You’re not alone!
In this article, I’m diving into the nitty-gritty of wood fillers – from the trusty epoxy to the versatile DAP – and revealing the secrets to making your screws stick, literally.
Yes, you can screw into wood filler, but the effectiveness depends on the filler type. Epoxy and DAP plastic wood fillers are best for this purpose, offering strong, durable results.
Wood fillers are used to fill holes, blemishes, dents, and other imperfections in wood. Sometimes we make those imperfections ourselves; sometimes, a screw rips out and needs to be replaced. Wood fillers generally contain real wood in the form of sawdust and real wood fibers. These fibers are suspended in a medium to bind them, whether water-based or petroleum-based, and the filler dries to a hard finish.
Wood fillers can be applied with a finger to push it into the hole being filled or with a putty knife again to push it into the hole. Although they dry hard, they add no structural strength to the wood surrounding them.
Wood fillers are untinted and carry only the color of the wood the sawdust or wood fiber came from. Once fully dried and cured, these fillers can be sanded smooth to the surface of the wood, and all rough edges can be removed and can be stained or painted. The fact they dry and cure hard and are stainable distinguishes them from wood putty.
Wood fillers, as we said, can be water- or petroleum-based, and each performs a little bit differently and fits different needs.
Water-based Wood Fillers
Water-based wood fillers tend to be a bit more crumbly in consistency, and since they are water-based can be supplemented with a little water to make the consistency a bit smoother. Fingers and putty knives can be cleaned easily with a little water.
Water-based wood fillers dry quickly; some can dry in as little as 10 minutes. Their consistency makes them a bad choice for finished wood and a good choice for unfinished wood that will be more porous.
Petroleum-based Wood Fillers
With respect to consistency, you will find petroleum-based wood fillers much smoother and with nothing further needing to be added for that smoothness. They will also be more effective than water-based fillers in protecting wood against humidity and moisture.
Homemade Wood Fillers
A wood byproduct and a medium are the constituent parts of a wood filler, and as such, you probably have all you need already in your shop if you are of a mind to make your own. A bit of glue and some sawdust mixed together to the desired consistency can be an effective wood filler.
Use it the same way you would a store-bought wood filler. Allow the glue to dry (follow the guidelines on the glue container), sand it smooth, and apply your choice of finish.
Is Wood Filler Durable?
It is, yes. It dries quickly and can be worked shortly after. It can be sanded after 30 minutes, and your project can continue, whether it’s a new one or a repair job.
It’s important to understand where wood fillers are used, too. Yes, they dry quickly and hard, can be sanded, and thereafter stained or painted. But, they belong to interior projects. Wood fillers are vulnerable to changes in the environment – expansion and contraction due to temperature and moisture variations.
The inside of your house is a pretty static environment, with no wild fluctuations in temperature or humidity. Wood fillers are the right choice for interior projects.
Another type of wood filler, wood putty, is a different story. This product is soft and pliable, and while it will fill holes in wood, it is better suited for finished wood rather than raw wood that would be damaged by its chemical composition.
It does not dry hard as wood fillers do and can not be sanded. Rather, you smooth it out as it is being used, either with your fingers or a putty knife. Exterior use, or uses in rooms where you expect there to be fluctuations in temperature or humidity, is recommended.
Another Type of Wood Filler – Epoxy
Epoxy for filling wood is another type to consider. Epoxy wood filler is used in putty form as well as a pourable liquid form. It will fill any hole, any gap, or any crack in wood and can even be used as a coating to prevent further damage or decay.
You can consider epoxy your best choice for repairing wood that is showing some decay or has been damaged. It is easy to use and acts quickly.
Bondo Home Solutions Wood Filler is a better-known name in epoxy fillers. It’s a good product and is a quick and permanent solution for any wood repair need you may have. It strengthens the wood, perhaps a piece of furniture like a wooden chair or table. It dries in about 15 minutes and can be sanded after that.
Bondo won’t shrink and forms a very strong and durable bond. Unlike the other wood fillers we’ve mentioned, it can be used for both interior and exterior applications. It’s water-resistant, and once it has dried, it acts just like wood – it can be stained or painted, and your furniture will look new.
One More Type of Wood Filler To Mention
We’re at the last item on today’s list for wood fillers to consider – this time, plastic wood. These latex-based fillers create a surface that looks and acts just like real wood. The best known of the plastic wood fillers is DAP.
When it has dried, it can be sanded smooth to the wooden surface, cut, planed, drilled into (for pilot holes to align screws, as well as the screw holes themselves), nailed into, screwed into, painted, or stained, just like real wood. In fact, when drilling into DAP, a pilot hole is a good idea – it will guide the screw into the center of the hole where it will be most effective.
Of all the wood fillers mentioned, DAP will dry to the hardest degree and will be 3-times as strong as the wood. Epoxy comes in second. Water- and petroleum-based wood fillers, the softest of the hard fillers, come in third unless a hardener is added.
Hardeners For Wood Fillers
Hardeners are available for adding to wood fillers. These hardener products create a chemical reaction with the wood filler, and this catalyst both hardens and strengthens the filler. Hardeners also speed up the drying process and allow you to work with the filler sooner – sanding, staining, painting, etc.
You can purchase hardeners for wood fillers in a tube or in a can. Minwax Wood Hardener comes in liquid form, and a little dab will do you – a small amount mixed with your wood filler of choice. Be sure to mix only what you will actually need, and work quickly. The hardener will help the wood filler dry in about 5 minutes.
In fact, it dries so hard that you can use a razor blade to cut off and shape a small piece of the hardening wood filler as it is set to fit the particular hole you are repairing or filling.
Using Screws With Wood Fillers
Now that you have a variety of wood fillers to choose from and understand their various constitutions, you have a good idea of which ones can take a screw.
We know that DAP can handle screws easily and well, and the same goes for epoxy wood fillers. While hardeners do improve the strength of wood fillers, this option would come in third after DAP plastic wood and epoxy.
We mentioned that DAP will dry up to 3 times as hard as the wood, and that’s why we put it at the top of the list of your options for screwing into wood fillers. After that, though, there are ever-lessening degrees of strength you will achieve screwing into wood fillers.
As you move down that list, consider the weight that will need to be supported by the repair you are performing. If the weight-bearing load to be carried is light and will not experience any undue stress, screwing into the wood filler will work for you. If the weight to be borne is greater, move up the list to either the epoxy or plastic wood (DAP) choice.
Want to see it in use? Here’s a video showing the use of DAP to repair stripped screw holes that can’t be moved.
Can screws go into wood filler? Yes. Will it be successful? Yes, it is possible with the right wood filler and will give you good results.