When it comes to covering up unsightly blemishes in wood, both wood putty and wood filler can be extraordinarily useful tools to have in your arsenal. While they’re sometimes confused with one another, there are several distinct differences between the two – both in terms of dry times and application.
Using wood putty or wood filler often comes in handy when you need to cover up the holes left by finishing nails, conceal small blemishes, or disguise unsightly mismatched joints. No matter what you’re working on, having an idea of how long your wood putty or filler will take to dry makes planning out your project that much easier.
Let’s take a closer look at wood putty and filler in more detail, and break down their respective dry times.
Wood Putty vs. Wood Filler
While the terms ‘wood putty’ and ‘wood filler’ are commonly used interchangeably, strictly speaking, these are two different products with distinct use cases.
Wood putty is a pliable non-hardening paste that dries firm but not completely hard like wood filler. Its sometimes referred to as “plastic wood” and typically consists of plastic chemicals, oil-based compounds, and often a pigment. The pigment is used to match the color of the putty with the color of the finished wood.
It’s commonly used for fixing small blemishes on finished projects like brad nail holes and joint blemishes. Because it doesn’t dry completely firm, it’s typically used to fill very small holes, where a total cure is not necessary.
Wood filler is made from wood particles and fibers mixed with a binder and a thinner. After the filler is applied, the thinner evaporates causing the filler to dry and harden. This leads to a strong bond with the wood.
Because it hardens, it helps the existing wood maintain its integrity. Keep in mind wood filler is not a true structural material and is not designed to improve the strength of joints. It’s also not meant to be used as a replacement for mechanical fasteners.
Wood Putty Applications
As mentioned previously, wood putty is typically used to cover up small blemishes left by brad nails, finish nails, and other minor imperfections. Due to its flexible nature, it will expand and contract with the wood during changes in temperature and humidity. This makes it ideal for use on outdoor projects, where wood tends to shift and move over time.
Because it’s designed to be used without sanding, wood putty needs to match the color of your finished wood. That’s why you’ll typically find wood putty sold in a wide variety of colors and tints – so you can match the putty with the wood finish.
Wood Putty Dry Times
As wood putty is non-hardening, it doesn’t dry in the sense of becoming hard to the touch. Some wood putties will dry to a certain extent, while others will remain pliable and flexible indefinitely.
Wood Filler Applications
Wood filler has a wider range of uses and applications than wood putty. Because its sandable, paintable, and able to take fasteners, it has a wide range of uses including repairing cosmetic damage, wood rot, holes left by nails or screws, or small gaps between joints.
As wood filler lacks the flexibility and pliability of wood putty, it’s commonly used for indoor applications where wood expanding and contracting is less of an issue. Most indoor wood fillers are water-based and are comprised of cellulose, gypsum, or wood fibers. Due to being water-based, they tend to have less odor and emit fewer volatile organic compounds (VOCs). They also dry quickly and only require soap and water for cleanup.
Wood filler also comes in exterior formulations, which are designed to resist shrinking and cracking from changes in temperature, humidity, and moisture. This type of filler is often oil-based, has a higher VOC content, and takes longer to dry than water-based fillers. It also requires acetone or something similar for cleanup.
There are also interior/exterior rated wood fillers, which combine the toughness and versatility of oil-based fillers with the quick-drying of water-based wood fillers.
Wood Filler Dry Times
So how long does it take wood filler to dry?
The answer depends on which type of wood filler you’re talking about. Water-based wood fillers dry faster than their oil-based counterparts, so it’s important to determine which type of filler you’re dealing with.
Additionally, dry times will vary based on the depth of your application. As you would expect, shallow repairs will dry faster than deep ones, with deep repairs sometimes requiring multiple coats to fill.
Water-based wood fillers typically take between 30 minutes and an hour for a single shallow repair to dry. For a deeper repair with multiple layers, you can expect the filler to dry in two to six hours.
Oil-based wood fillers take longer. You can expect about 10 to 20 minutes for the surface layer to dry, but It will take significantly longer for a full cure/dry.
After the initial surface layer dries, you can wipe away any excess material. After that, it will take between 12 and 48 hours for the filler to dry completely.
Tips for Faster Dry Times
Like other construction materials like concrete or Bondo, temperature and humidity can have a significant impact on wood filler dry times.
- Apply in Thin Layers: Thick layers of wood filler take significantly longer to dry than thin ones. If your application requires a thicker layer of wood filler, consider applying the filler in multiple thinner coats. This will result in a quicker overall drying time.
- Apply During Warmer Weather: Consider applying wood filler during the warmer midday hours, as the increased temperature will accelerate the drying process.
- Use a Fan: Setting up a fan will increase the air circulation in the workspace. This will remove humidity and lower dry times.
- Heat up the Filler: In addition to applying the filler during warmer weather, you can also increase the temperature using a space heater, thermostat, or heat gun.
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