When repairing furniture and other wooden items or building them from scratch, there are many instances where you will need to fill holes. These holes can be a result of defects or inconsistencies in the wood or where the nails go in.
And when it comes to filling holes in a workpiece, wood filler and wood putty are always the best and in most cases the only solutions.
Wood putty and wood filler are often used interchangeably by woodworkers to mean the same thing. While they serve an almost similar purpose, they are still different products and suitable for different wood filling projects.
Knowing the difference between a wood filler and putty is vital for every woodworker as it makes it easy to pick the right product for a project.
Something I’ve learned during my time on this planet is that people make mistakes. Fortunately, there is usually a way to fix the problem, which is why pencils come with erasers, right? The same is true when it comes to home improvement and woodworking projects.
Doing projects at home requires a lot of patience and some skill, but what happens when you make a mistake? What if you make a hole bigger than it’s supposed to be? Unfortunately, that means you might have to scrap the whole thing, right?
However, there are ways to correct these mistakes that won’t cost you an arm and a leg. Wood filler and wood putty are a couple of common items you can use to fix defects or repair mistakes. It’s important to know the differences between the two so you know which one to use.
Let’s take a closer look at wood filler and wood putty, along with how they can be used to address mistakes or imperfections in your project. Before we get too far along though, let’s take a second and consider the differences between the two.
At Hitch Property Constructions, we offer timber repairs work from simple timber repair to almost new structures, renovations, and extensions.
Wood Putty Is Oil Based and Remains Flexible
Most wood putty products are similar to plumber’s putty or window glazing. They are oil-based, so they resist moisture, and they may harden, but they never completely lose their flexibility. These qualities make putty most suitable for exterior applications because it won’t wash out, and it won’t crack with expanding and contrasting wood.
Putty generally comes in small containers because its main use is for patching small holes on finished wood, and a little goes a long way. You can’t stain putty, but it comes in a variety of wood tones, and you can usually find one that is a reasonably good match.
Because putty is oil-based, you technically shouldn’t paint over it with a water-based product. If you use a small amount of putty and give it several days to dry, however, there shouldn’t be a problem.
Wood Filler May Be Water-Based, and You Can Sand It
Perhaps the best-known wood filler is Plastic Wood, manufactured by DAP. It’s a solvent-based product, but many similar fillers are water-based. Common ingredients in wood filler include cellulose, as you would expect, along with limestone and attapulgite, which are two of the main ingredients in the joint drywall compound. DAP also makes a water-based product, Plastic Wood Latex Wood Filler, which contain limestone but no cellulose.
Two-part epoxy-based wood fillers blur the line between wood putty and wood filler. Epoxy wood filler is a pure plastic that can be used on finished or unfinished wood. It contains no cellulose, but because it cures hard enough to sand, it’s closer to a filler than a putty.
Neither of these products should be confused with wood-grain filler, which is used primarily by finishers. It’s very thin, and you spread it on a tabletop or countertop and sand it flat prior to applying the first coat of finish. It creates a level substrate for the finish, and the result is a glassy-smooth surface.
Filler Works Best Indoors
Manufacturers don’t conform to any particular standard when designating a product as a filler or a putty. Still, in general, a filler is infused with pigment to match a certain type of wood and is intended to be coated with a clear finish. It isn’t flexible, and it cracks when the wood expands and contracts. Moreover, direct sunlight dries it out and makes it shrink. If you use a wood filler to fill an outdoor crack or hole, it will probably fall out in a year or two, even if you paint over it.
When Outdoors, Use Two-Part Putty
Even though putty doesn’t harden by itself, you can buy two-part products that undergo a chemical reaction to turn hard. These materials bond well and wear better than the wood itself. Cured putty doesn’t resemble wood, however, so you have to paint it. Some carpenters use auto body filler — which is a two-part fibreglass putty — to patch exterior wood. The fact that it’s grey is immaterial when it’s under a coat of primer and paint.
Overview of Wood Putty
Wood putty is often referred to as “plastic wood.” It is one of the most popular wood filling compounds in many workplaces and seems to be the default option whenever you need to fill a hole or fix a defect. However, this substance isn’t the best in every situation.
How it is Used
Wood putty is used after you stain or varnish your workpiece. For this reason, it is great for workpieces that have already been finished that need a touch-up if you’re repairing the furniture, wood putty maybe your best option because of this.
Wood putty should not be used on raw wood because it often contains chemicals that can be potentially damaging. It feels like soft clay and can often be quite stiff. Because of this, you will usually need a putty knife to apply it. It is not the easiest filler to use because of this. It reminds us of plastic resin.
Once you’ve applied it, you have to let it dry for an extended period. Despite some wood putties being advertised as “fast-drying,” all of these products take a long time to harden. Sometimes, you have to mix the putty with hardening chemicals to get it all the way dry. However, other brands harden by themselves. It just depends on what you purchase.
This long drying time can seriously affect the colour of your final results. Most lighter colours darken when they are dry, so you often need to purchase a colour that is lighter than you think you need. The putty can also accumulate dust and debris while drying, which is another problem of its own.
Because wood putty is so popular, there are a lot of options currently available on the market. You can find tons of different brands and many different colours. We expect that you can find a matching putty for even the wackiest-coloured products.
Wood putty is made a variety of different ways depending on the brand. All wood putty is oil-based, but the exact oil varies widely. The most common oil used is boiled linseed oil, but others can be found on the market too.
Wood putty also contains a colourant, which gives it it’s wood-like colour. Most contain calcium carbonate as well. If you need to add a chemical hardener to your chosen wood putty, you have to take those chemicals into mind as well.
Wood putty doesn’t cost very much, and it lasts forever. You do not have to worry about this product coming off or decaying any time soon. This makes it an excellent choice for outdoor furniture, which is typically sitting out in the elements.
Overview of Wood Filler
Wood filler is a bit different from wood putty and designed for very different circumstances. They are not interchangeable in the least.
How it is Used
Wood filler is applied before your finish or stain. It will not damage raw wood-like wood putty will. It is much more of a putty-like compound, which can make it very easy to use. It spreads nicely and stays put easily.
The wood filler also dries very quickly. In most cases, even a large glob of wood filler will start drying in as little as ten minutes. All types of wood filler will be dry in less than 24 hours, though many types dry long before that. “Fast-drying” options are available if time is of the essence.
Check out our range of timber repairs Melbourne at Hitch Property Constructions.
Most wood fillers come in a neutral colour. This means that you may need to colour them to match your wood. However, you do apply them before your stain, so this is less of an issue. It is highly recommended to mix the filler with sawdust from the wood you’re using, as this will make it look more natural.
Wood filler is made with various products, including epoxy, lacquer, and clay. Latex is one of the most common types, as it is water-based for easy cleanups. This type also mixes well with dyes, allowing you to use it for larger holes without making the wood piece look two-toned.
Epoxy and polyurethane may also be handy to have in your workspace. However, they require a bit more sanding. You should sand them before you add a finish.
Wood filler costs about the same as wood putty. However, it is not as durable, meaning you have to do more repairs over time. It is not suitable for outdoor furniture because it will not expand and contract with the wooden furniture. Instead, you’ll end up with cracks.
Sunlight can also make this material crack and dry-out, which may lead to more repairs. These repairs can add up and cost you more money in the long run.
Furthermore, this material is usually used for large cracks, so you’ll probably use more.
Why Use Wood Filler?
There are plenty of benefits to using wood filler, so let’s review a few of them here.
While it’s important to create good, quality work no matter what the project, sometimes it’s nice to have something that works quickly. Wood fillers are perfect for a scenario where you need to get something done in a hurry.
Once you apply wood filler, it dries quickly. Of course, drying time will depend on the type of wood filler and the product you select; however, many options on the market can dry in 10 to 20 minutes.
Ideal for Porous Surfaces
Fillers are ideally suited for work on porous surfaces. If you discover that the surface you’re using isn’t working very well, try sanding it down before you apply wood filler.
Also, keep in mind that wood filler is great if you’re working with unfinished lumber. If you apply wood filler to a finished project, you’ll discover that the surface is uneven and bumpy. The challenge here is that you’re going to have a hard time smoothing it down.
On the other hand, if you use an unfinished surface that already has holes, you can use the wood filler and then sand it down later.
Great for Filling Big Holes
The great thing about wood filler is that no matter how big or deep the hole is, it’s there to save your project. It can be difficult to find anything better when it comes to repairing cracks or holes in the surface of the wood.
If you do need to use wood filler to repair a big hole, remember to smooth out the surface beforehand with some sandpaper. After you’ve used the wood filler, allow it to dry, then paint it to get a nice, smooth finish.
When Not to Use Wood Filler
Something to keep in mind before you apply wood filler to your project is that wood tends to shrink or expand depending on weather or other environmental factors.
The problem here is that wood filler doesn’t offer the flexibility needed to adapt to this shrinking and to expand. As a result, it tends to break easily, which means it’s best to use wood filler on furniture or wood projects that will remain indoors and away from environmental changes.
Now that we’ve covered what wood filler is and when it’s best to use it let’s switch gears for a bit and talk about wood putty.
Where wood filler is usually used on unfinished wood, wood putty is typically applied already varnished and stained surfaces. You may also hear it called “plastic wood.”
Even though there are a variety of methods used to create wood putty, the vast majority of manufacturers make theirs of oil-based components and calcium carbonate. As a result, when you add water to the mixture, the wood putty behaves like soft clay.
This clay-like consistency gives the wood putty the ability to stay wet for long periods, so if you’re working on a project that requires a quick turnaround, you may have to search for alternative methods.
When using wood putty, it’s ideal to use it on finished surfaces. This is due to the chemicals it contains, which you shouldn’t use on raw wood. After you’ve applied the wood putty to your project, be sure to wash off any extra residue and be sure to sand it down to get a smooth surface.
Why Use Wood Putty?
There are several reasons to use wood putty with your most recent woodworking project. Let’s take a look at a few of them.
Easy to Apply
One of the best things about wood putty is that it’s easy to apply to nearly any type of wood surface. You can use a putty knife to cover large areas or your finger to dab a bit on smaller areas.
If you find any extra wood putty on the surface of your project, grab a damp rag and wipe it off, then let it dry until it sets.
Various Shade Selection
Stained and finished surface take on certain shades and textures, so it only makes sense that wood putty comes in options that match. It’s imperative that you select a wood putty with similar tone and shade, so your repair doesn’t draw attention.
So as you go about working on your wood project, be sure to find a tone that matches the surface of the wood you’re repairing.
No Additional Adhesives Required
Wood putty is a great product for fixing cracks and holes, but many people don’t know that it can also behave as a sealing agent. Why does that matter? Because it means you don’t have to purchase an additional adhesive sealer for the surface of your project.
One last way that wood putty is beneficial is through the savings it provides over the course of time. That’s because wood putty is durable, which means you don’t have to fix the repair over and over.
The nice thing about wood putty is that even if you purchase one of the smaller containers it comes in, you should still have plenty to last for a few projects. If you don’t need to use all of it, be sure to store it in a cool, dry place.
Why Not Use Wood Putty
Perhaps the biggest reason not to use wood putty is due to the potential harm it can cause raw wood. Because of the ingredients used to make wood putty, using it on unfinished timber can result in damaging the surface of your project before you’re able to stain it.
We have a wide range of Melbourne timber repairs for your home renovations. Check out Hitch Property Constructions.
Should I Use a Wood Filler or Wood Putty?
Anytime you need to patch small imperfections in a finished surface, you should use wood putty. Lacquer-based patching pencils, which are intended for minor repairs to furniture finish, are putty sticks. Because it resists the elements better than wood filler, putty is the go-to product for exterior repairs.
Because it’s sandable, wood filler is the only thing you should use for patching interior unfinished wood. If you plan to stain the wood, choose a wood filler that contains cellulose because it stains better than limestone. No matter which filler you use, especially epoxy filler, it won’t stain the same colour as the surrounding wood, so most woodworkers use prestained filler for furniture, floors and other woodwork.
Unlike wood putty, wood filler contains no adhesives, so it won’t bond to the wood unless you seal it with paint or clear finish. This means that you should use putty to make repairs on finished surfaces, even indoors. Remember, you don’t always have to leave putty unfinished. If the repair is fairly small, and you give the putty time to dry, you can coat it with lacquer, varnish or even water-based polyurethane.