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Wood Putty vs Wood Filler

Ever wonder what to use between Wood Putty or Wood Filler. This article features the difference between wood putty and wood filler and their uses.

Man applying varnish in a wood with protective rubber gloves.
Woodworking can be tricky when you don’t know exactly what to use to do some patching up. Ever wondered what to use between Wood Putty or Wood Filler, and ask yourself which is better? I took the liberty to research it and find out exactly when to use these two applications.

Wood putty, as it says in its name, is a putty mixture that doesn’t harden once applied, making it ideal for wood that is exposed to the elements outdoors. Wood Filler, on the other hand, is used more for indoor purposes and to fix big major holes as wood filler hardens once applied.

Choosing between these two can be tricky, but all comes down to how the wood you’re working on will be used. Wood putty is made of plastic chemicals and oil-based compounds, whereas wood filler is made of wood particles mixed with a binding agent.

Wood Putty

Applying wood putty above the nail using a putty knife.
Wood putty is nicknamed plastic wood due to its composition. Wood putty is usually applied to wood with finishers, such as varnishes and stains. They come in different color mixes, making it easy for people to apply specific color wood putty to a stained wood so that it blends with the color of the wood.

Wood Putty, unlike wood filler, doesn’t dry and harden to a solid-state; therefore, it isn’t suitable for raw wood. As mentioned above, it’s used mostly for outdoor wood that faces the elements of wind, rain, and sun heat. All these elements make wood twist, expand or contract, making wood putty perfect as it can adjust to the weather with the wood.

Wood Putty is flexible and can be easily applied to a surface by using a putty knife to spread it into the cracks or holes you want to fill. After the putty has dried little on the surface, you can sand it with sanding paper to make the surface smoother. Wood Putty needs to be stored in a dry, cool area where it could last for 20 years before it is unusable.

Wood Filler

Wood Filler dries rock hard as the composition of it consists out of sawdust, or wood dust, that is suspended in a binder, such as water or a petroleum-based mixture. Wood Filler doesn’t come in a tint or color as wood putty does, so when applied to wood, the wood filler stains according to the wood it is applied on. Wood filler drying rock hard doesn’t add to the integrity of the wood as most people think.

Wood Filler comes into basic mixtures being water-based and the other petroleum-based mixture. So you might be asking what is the difference between these two and what should you choose right?

 Water-based wood fillers can be identified as they are more crumbly in texture, but this can be adapted by changing the mixture of the water mix. Water-based wood fillers usually dry after 15 minutes, once applied to the wood. They also don’t necessarily need to be sanded afterward as the surface can be adjusted or cleaned by soap and water.Man applying wood filler on a damaged wood.

Water-based wood fillers are sometimes considered to be more versatile than solvent-based wood fillers. The considered such as they can be diluted with water and more commonly used in projects requiring thinner filler to fill in finer detailed cracks or holes.

Petroleum-based wood fillers give a much smoother texture and consistency than its counterpart. Petroleum-based fillers are useful in sealing the outermost surface of wood, protecting the wood against elements that could cause damage to the wood.

This type of wood filler takes up to an hour to dry before a person can work with the surface. Instead of using water, a strong mixture such as turpentine or acetone is needed to clean the surface. They are also more suited for exterior purposes as they are more resistant to water, humidity, extreme heat and cold, and rot.

Is Wood Filler Paintable?

Wood filler is paintable, however, the right steps must be taken in order to ensure that it is prepared for the paint, or else if you just paint over it, you will see it through the paint as a spot. Therefore what one should do is first sand the filler down, to make the surface of the wood with filler nice and equal. After sanding, make sure you use a wet rag to clean the surface from any dust.

After the surface has been sanded and cleaned, a primer should be prepared to paint over the surface that you want to paint. Apply the primer with a paint roller to get a neat and equal finish of primer on the surface, which will hide the filler and give you a base to paint onto. Then paint over the primed surface after the primer has dried for about 2 hours.

Is Wood Putty Toxic

Wood putty in a plank of wood and a putty knife.
If you have ever worked with wood filler or wood putty, you would know that feeling when you first open up that bottle and a strong chemical smell hits you. A lot of people link that strong smell to toxins and strong chemicals that could be harmful. No one wants their children or pets to end up playing with something that might get them hurt right!

Thankfully Wood Putty isn’t considered to be toxic once it dries, but the mixtures can cause vomiting and irritation if by accidentally digested by a person or animals. Wood Putty and Wood filler both are inherently nontoxic and have little to no impact to nature as most of them are made from natural substances.

However, it is advised that these fillers be stored in a safe place where they cannot end up in either your children’s or pets’ mouths. If either ingests it, it would be safe to take them to the hospital to make sure that the fillers don’t harden in the mouth or on their way to the stomach.

Conclusion

There isn’t really a factor of which is better than the other but more which is suited best for what needs to be fixed. It all depends on the application, if it’s to fill in a gap for exterior stuff, then wood putty is better suited. Wood putty is cheaper than wood filler. However, the wood filler will give you a more aesthetically appealing finish but is used more for indoor purposes.

Sources:
Wood Putty vs. Wood Filler: Which Should You Use? (usvintagewood.com)

What’s The Difference Between Wood Putty and Wood Filler? – Vintage & Specialty Wood (usvintagewood.com)