Does Wood Putty Harden?

Applying wood putty on the wood cracks.

If it is your first-time using wood putty, you might ask if it hardens when it dries. The answer, of course, is “No, it doesn’t!” After applying the wood putty, it will dry and set within several hours. Yet, it doesn’t harden but maintains its flexibility. This unique characteristic of wood putty lets it resist contraction, expansion, or any alteration in the wood dimensions.

Unlike wood filler that dries afterward, wood putty is malleable. You can use it to fix minor dents and scratches on the wood. Besides, you can buy this product in crayon-like forms (sticks) or small jars. 

Compared to wood filler, wood putty comes with a greater density. Besides, it is very pliable that you can effectively apply it using a putty knife. Since it doesn’t harden, it won’t crack or shrink. Additionally, it doesn’t allow sanding, and you can never stain it. However, many putty types get colorized to suit the wood tones.

Reasons Why Wood Putty Doesn’t Harden

Wood putty is pliable and doesn’t harden because it is wrought in pliable resins. These flexible synthetic resins have chemical structures that prevent hardening over time. It consists of oil-based solvents and a plastic mixture designed not to crack or shrink over time. Besides, it doesn’t have sawdust, an agent that solidifies putty into very compact material after drying. 

Nevertheless, you can also cause the wood putty to harden. You can do this by adding a special hardener. This hardener enables the wood putty to dry and harden, transforming the wood putty into a solid form.

Is This Non-hardening Property of Wood Putty Beneficial?

Well, if you’re a regular user of wood putty, you will appreciate this non-hardening property of wood putty. First, it prevents the putty from cracking and breaking away when the wood expands or contracts. But why does wood contract or expand? 

Wood, of course, expands or contracts due to the vicissitudes of the weather. Wood is not impervious to these changes. As such, you will often find them changing their dimensions depending on the temperature and weather. 

If the putty hardens, it will most likely crack and split from the wood. It would most likely be incapable of adjusting to the changing dimensions of the wood. 

For example, if you fill with wood putty a nail hole, the putty will adjust to the changes in the dimensions of the hole. Thus, it will remain reliable and durable. 

Another thing is that wood putty will not likely damage the wood. For example, if the wood contracts, the wood putty will only adjust its size to accommodate the wood’s contraction, preventing the wood’s cracking. 

You would often use wood putty on finished wood, for if you use it with unfinished wood and stain it afterward, it will result in a blotchy wood surface. So, you can avoid this outcome by using wood putty after applying the finish. The good thing about wood putty is that it comes in a wide array of colors allowing you to choose the best color for your furniture. 

How Much Time Does Wood Putty Need to Dry Before You Can Sand It?

You may sand right after the wood putty has dried. However, the drying time of wood putty may vary depending on the size and the type of putty you are using. If you’re using oil-based wood putty, you can expect it to dry after an hour. Yet, it will take around a day before you can sand it. 

On the other hand, water-based fillers may dry in half an hour. It will take around 2 to 4 hours before you can sand it. But once it has dried enough and you’ve allowed the necessary time to pass by, you can sand it afterward. 

Tips on Making Wood Putty Dry Fast

You should consult the product manual to know how much time is needed to get the wood putty to dry. Besides, evaporation must happen to get the wood putty to dry. You might ruin your workpiece if you don’t let it dry completely. And if you want to speed up the drying process, you can employ the following steps:

Apply Consistently Thin Wood Putty Layers

The proper application of wood putty involves applying it in thin and consistent layers. The reason is that thick layers will likely dry slowly. You can use a putty knife when applying the wood putty to ensure that you apply thin layers consistently. Apply about 1/8″ of wood putty consistently to let better absorption and evaporation occur. 

Apply Evenly the Wood Putty

Ensure that you apply the wood putty evenly because it may shrink or crack if you use it inconsistently. It will be best to limit the coating to two thin coats. 

Apply It Away from Flame

When applying wood putty, you must ensure that you do it away from open flames because wood putty is solvent-based. Hence, it may catch fire if it is near any open flame. 

Utilize Exhaust Fan

When applying wood putty, ensure that you work in a well-ventilated area where the air circulation is good. If the air is still, you can use an exhaust fan to make the air circulate. The exhaust fan can help you remove humidity in the air, leading to a faster drying time. 

Increase the Temperature

Since evaporation hastens the drying process, you can increase the puttied surface’s temperature to 50ºF or greater. If you have a space heater or any kind of heater, you can turn up its thermostat. Besides, you can use a blow dryer to up the temperature of the puttied surface. 

Wood Putty Vs Wood Filler: Which is Better?

If you’re a beginner in using wood putty, you might get confused between wood putty and wood filler. These two products, however, have an almost similar purpose—to fix minor damages and enhance the appearance of the wood. But they are not the same. Thus, it will help to know when to use wood putty and when to use wood filler. Besides, it will help to know the pros and cons of using these two products. 

These two products, however, can act as a wood hole filler. However, you should only use the putty on stained or finished surfaces because it contains chemicals that could damage bare wood. However, the wood filler should be used prior to staining or finishing. Furthermore, wood putty, as mentioned above, doesn’t harden, while wood filler hardens when it dries. 

When Do You Use Wood Filler?

Since the wood filler tends to crack and shrink due to the changes in the temperature, it is not good to use it outdoors. Besides, wood filler dries fast and hardens. So, if you need a quick interior repair of your wooden furniture, you can use wood filler to repair the scratches and holes in your hardwood furniture or flooring. Moreover, it is perfect for repairing unfinished furniture and damaged wood edges. 

You can shape or mold the wood filler to complement and match the furniture’s undamaged edges before the filler hardens. Afterward, you can sand the surface to provide a smooth texture before applying a stain. 

When Do You Use the Wood Putty?

The wood putty is not as popular as the wood filler. The reason might be that it dries longer. Besides, it doesn’t harden. However, this characteristic of wood putty might be an advantage because it is well suited for outdoor repairs. Since it doesn’t crack or shrink, it doesn’t cause the wood to crack. Besides, you can paint it over to suit the surrounding wood. 

You can use the wood putty to repair chips, small holes, and cracks in indoor furniture. Nevertheless, you should consistently apply a thin coating to ensure a faster drying time. 


The question of whether wood putty hardens is a question often asked by beginners in the use of wood putty. Wood putty, of course, doesn’t harden, and this characteristic may initially seem to be a limitation of the wood putty. Yet, it is, in fact, a useful property that could prevent damage to the wood in the long run. 

Wood putty can be used both outdoor and indoors. You can use it to fill dents, small holes, and cracks in furniture. You can also fill gaps and gouges of exterior wood. Lastly, you can use it to prevent the spreading of cracks.  

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