how to use wood filler on trim?

When you’re working with wood trim, and especially if you’re painting or staining it, you may need to fill the gaps between pieces of trim.

This post will walk through the best ways to use wood filler for this purpose, from choosing which type of wood filler is right for your project to get a smooth finish when applying it.

How do I get a smooth finish with wood filler?

Smooth the wood filler using a putty knife. Use a wet cloth to remove excess. Let it dry for 24 hours before painting.

What is the difference between wood putty and wood filler?

Wood putty and wood filler are both used to fill the imperfections in wood trim. But there are some subtle differences between them that you should know about before you start using your new product.

Wood putty is softer and more flexible than wood filler. This makes it particularly well-suited for filling holes or gouges, which can be caused by a variety of factors ranging from old nails leaving jagged edges behind when removed to damage caused by a carpenter’s nail gun going off course.

It’s also ideal for areas where you don’t need as much structural strength since the putty will compress easily when pressed against the surface around it.

Wood filler, on the other hand, has a harder consistency and is less likely to provide added flexibility when you’re trying to press it into place.

Because of this quality, it’s often used in place of putty even if there aren’t any holes or gouges present—for example if there is simply an area where two pieces of trim meet that doesn’t have many gaps between them but could use some additional support anyway (a common example would be around door frames).

How do you use wood filler before painting?

For small gaps and scratches, you’ll want to apply wood filler to the gap. You can buy wood filler at hardware stores or home improvement stores.

Once you’ve applied the wood filler, let it dry for a few hours before sanding it down with fine sandpaper—rough sandpaper will leave marks on your paint job and make your trim look bumpy instead of smooth.

Once the filler is dry, use a damp cloth and wipe off any excess residue from around your patched area so that you don’t have to worry about getting paint on any other part of your trim when painting later!

Is it better to use wood filler or caulk?

Wood filler is a filler, and caulk is a sealant. If you need to fill a gap, wood filler will do that for you. If you need to seal the gap between trim and wall or flooring, caulk is better suited for the job.

Do I need to prime wood filler before painting?

  • No. It’s not necessary to prime wood filler before painting, but it can make for a better-finished product if you’re using oil-based paint. Primer will seal the wood, making it easier to paint and preventing dirt from seeping into the pores of your trim. If you’re using latex paint, however, it’s not necessary—the surface of your trim will be impervious enough without any primer intervention.

Can you apply wood filler with a brush?

You can use a brush to apply wood filler, but it’s not recommended for many reasons. First of all, you’re much more likely to get air bubbles in the wood filler if you’re using a brush rather than a putty knife or taping knife. Air bubbles are bad because they weaken the strength and integrity of your fill job.

Also, if you don’t clean off the bristles thoroughly before moving on to another step in your finishing process (say sanding), then there are going to be leftover bits of dried wood filler stuck in them which will end up transferring onto whatever surface happens next—that could mess up any finish coatings that are applied after this step too!

Finally, and perhaps most importantly: using an old paintbrush or other cheapie tools when applying an expensive product like Minwax® Wood Filler means risking damage or destruction of those tools altogether! Let’s face it: these days most people don’t keep a large supply of extra painting brushes around just waiting for something like this opportunity to arise where they need one…

How big of a gap can wood filler fill?

Wood filler can fill gaps up to 1/4 inch, but it can also be used to patch larger holes. If you have a large gap that needs to be filled, spread the wood filler thin and then sand it smooth after application.

Does wood filler harden like wood?

In addition to being easy to work with, wood filler can also harden like wood and be sanded down. This depends on the type of wood filler you use.

There are many different types available, each with different properties and uses. Some fillers are more elastic than others and can take on a slightly different shape after drying; this allows for easier application since it’s sometimes difficult to get an exact fit right away when applying one-part epoxy or polyurethane-based fillers that don’t adapt easily to curved surfaces such as the underside of an overhang.

When choosing between products based on viscosity (how thick they are), look for those listed as “sandable” in order to ensure proper adhesion before final sanding takes place.


We hope that this article helped you understand how to use wood filler. It’s a great product and can help you get the job done quickly, but only if you know how to use it properly!

If you have any questions about using wood filler, feel free to ask them in the comments below.

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Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

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