can you use wood filler without hardener?

Wood filler is a great product for repairing holes and cracks in wood. It’s easy to use, inexpensive and versatile.

But what happens if you don’t use hardener on your wood filler? Will it still work? This article will explore the answers to these questions and more!

What happens if you use wood filler without a hardener?

If you don’t use a hardener, your wood filler will not harden.

It will not stick to the wood.

It will not be waterproof.

It will not be a good finish.

And it won’t be durable (or able to be sanded). Plus it won’t even let paint stick on top of it!

Do you need to use wood hardener?

Wood hardeners are required when using a wood filler, but not always. If you’re using a plastic wood filler, you don’t need a wood hardener.

A lot of times you can use the same type of paint that you’ve already chosen for your project to seal the wood once it dries and give it protection against moisture and other outside elements.

If you’re using a traditional wood filler then there’s no way around having to use a hardener with it as both go hand in hand when working with these types of products.

Can you use a dry wood filler?

Yes, you can use a dry wood filler. Dry wood fillers are good for small repairs and they’re easier to sand. Dry wood fillers tend to be more expensive than wet versions as well.

You’ll find that dry fillers won’t adhere as well or give as much strength as their wet counterparts, but if you’re just filling in a small crack or hole, a dry filler will probably do the trick just fine.

Does wood filler strengthen wood?

Wood filler can be used to cover up small holes and cracks. It will not strengthen the wood, however, and it won’t make the wood last longer or more durable.

Why does my wood filler keep cracking?

If the filler you are using is not the right consistency, it can crack after it dries. The most common reason for this is when a filler is too damp.

A damp wood filler will take longer to dry and can be harder to get out of the container than a drier one.

Other reasons include:

  • The temperature in your house or garage is too warm or cold. Ideally, you should use a wood filler that will cure at room temperature (70 degrees Fahrenheit). If you live in an area where temperatures are below 50 degrees Fahrenheit in winter and above 80 degrees Fahrenheit in summer, then keep your wood filler inside until you need it so that its rate of curing remains consistent throughout the year.
  • You used the wrong type of material for what project you’re doing—for example, if there are small gaps between two pieces of plywood but they’re only 1/8″ wide instead of ¼”, then regular spackling compound would probably not work as well here because its texture was designed specifically for filling larger gaps. In situations like these where there’s no obvious answer about which kind(s) might work best together on their own merits…it’s worth trying out some different combinations before giving up entirely! Just remember not mix brands if possible because some manufacturers may use different ingredients which could react differently when mixed together under certain circumstances (like humidity levels).

Does wood filler expand and contract?

It’s important to know the temperature range of your wood filler. If you use it in a temperature range that is too high or too low, it can crack. If you use it in a temperature range that is too high, it can expand and crack.

If you’re using a wood filler that contains hardener and don’t want to add any more than what’s already included in the bag (and if there isn’t any way for moisture or humidity to come in contact with your project), then yes! You do not need to add additional hardener according to most sources I’ve found online.

What can I use to harden wood?

Can you put wood hardener on wood filler?

No, you shouldn’t put wood hardener on wood filler. Wood glue and wood filler are different products with different purposes.

They’re not interchangeable, so if you do use them together, the results won’t be as good as they could have been if you used them separately.

In fact, there are several ways in which using wood hardener with wood filler is a bad idea:

  • You can’t fix cracks in your base coat of wood filler before painting it because it will just cause those cracks to open up again when you apply the next coat of paint.
  • Wood glue doesn’t stick well enough on its own to hold two pieces of lumber together without any other support (like nails or screws). Adding more glue won’t make that bond any stronger; instead, it’ll just make things messy and sticky until everything dries out again.
  • You also don’t want to make your fillers too dry because this makes them weak enough that they can snap off easily when exposed to heat or pressure (like when drilling holes through a section of wall made out entirely from reclaimed materials).


So can wood filler be used without hardener? The short answer is yes, but it depends on what kind of wood filler you’re using.

If you’re working with an oil-based filler that doesn’t need to be mixed before application, then yes—you can use it without a hardener.

However, if you’re using a water- or solvent-based product (like latex-based), then you’ll need something like a lacquer or shellac to seal it after application.

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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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