Epoxy Wood Filler Guide – How to Use a Liquid Wood Filler
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For anyone who enjoys tackling DIY projects, epoxy is a fantastic substance. Epoxy can be used for several different tasks including fixing rotting wood. If you have old wood that would be difficult to remove or too expensive to replace, then using epoxy wood filler is a great option. Epoxy is particularly adhesive and strong when used to fill cracks and holes. You can mold epoxy putty into any shape and you can sand it down to ensure a stunning finish. Epoxy wood filler is easy enough for you to use at home. Our comprehensive guide will cover everything you need to know about epoxy wood filler, and how to use liquid wood filler.
Table of Contents
What is Epoxy Wood Filler?
Epoxy is available in a variety of forms and can be used to restore and maintain wooden items. As a wood filler, you will be using epoxy in the form of pourable liquid or a putty. Many jobs will require both forms. If there are any holes, cracks, or gaps in the wood, epoxy can be used to fill them to strengthen and retain the original structure of the piece of wood. Epoxy wood filler will also prevent any additional decay or rot by coating the surface of the wood.
Epoxy can adhere to almost any surface and is a very versatile and durable material. Epoxy can be resistant to chemicals, waterproof, scratch-resistant, and heat-resistant. When you restore wood using epoxy filler, you achieve a solid base for the wood.
Epoxy filler is made up of two components – the hardener and the epoxy. When you combine these two parts a chemical reaction occurs which causes the epoxy to cure (dry). You have to work relatively quickly once you have combined the two parts. You can pour liquid epoxy into the wood and the internal holes and cracks will be filled with the liquid. Wood filler putty is ideal for filling any holes on the surface of the wood. When your epoxy filler has cured, you can sand it down to achieve the necessary shape to match the wood.
When to Use a Wood Epoxy Resin Filler
If you have damaged wood that needs to be repaired there are different approaches you can take to replace or fill the wood. Epoxy can be thought of as intimidating and is not normally the go-to for most people for home renovation DIY projects. However, it is easy to work with to achieve a stunning, strong finish. Using epoxy yourself can also be a more affordable option than having the wood filled in by a professional or replacing the wood completely. So, when should you use a liquid wood filler?
If more than half the piece of wood is damaged you will, unfortunately, have to replace the wood. Also if you have had to do three prior epoxy wood fills to the wood you will need to replace it. It is also easy to replace the wood if it is a standard cut and easily available and affordable. You can use a dutchman’s patch if the wood needs to be clear finished or if the wood requires milling or drilling. The wood should be replaced if you need to maintain the original construction and wood species of the piece. Epoxy wood filler should be your go-to in one of the following situations:
- If there are cracks, rot, or holes in the wood but about 80% of the wood is still in fair shape
- If the piece of wood is uniquely designed and would be hard to replicate or replace, such as handmade or detailed pieces of turned wood
- I you would struggle to remove the piece of wood without removing or damaging other wooden structures
You have a few options when replacing and fixing wood. Usually, you would only choose to go the epoxy resin filler route under specific conditions. The epoxy can be applied from different angles, it can be soaked straight into the structure of the wood, and it can be molded with ease. What is great is that you can sand down your epoxy resin filler to shape it to match the original wood shape.
Advantages of Using Epoxy Wood Filler
Many people find epoxy a little intimidating. However, it is actually a very forgiving, straightforward substance to use. Here are some advantages to using epoxy wood filler:
- It assists in avoiding future decay by providing a good external sealer
- Once cured, epoxy is a durable and hard substance that can support the wood
- It can fill all internal passages and holes with ease
- Epoxy filler can adhere to all surfaces and shapes and will work with any type of wood
- Epoxy is surprisingly easy to use. You simply need to pour it, mold, and shape it accordingly
- You can apply the epoxy filler without having to remove the wood
- Epoxy gets into hard-to-reach places
The Best Epoxy Wood Filler
There are so many different liquid wood fillers available on the market that it can be difficult to select the best one. To help you with your decision we have listed three of the best epoxy wood fillers below.
Overall Best Epoxy Wood Filler: ABATRON WoodEpox 2 Gallon Kit
This is the perfect option for repairing rotted wood in an assortment of scenarios. This wood filler can rebuild missing portions of the wood and fill spaces to return the wood to its original glory. The compound will bond permanently to the wood and is easy to apply. Once you have applied the filler there is no need to be concerned about crumbling, shrinkage, cracking, or delamination. The epoxy wood filler is also sag-resistant and lightweight.
You can buy this two-part epoxy wood filler in gallon containers that, when combined, create two gallons in total. You have 20 minutes to use the substance once it has been mixed before it begins to cure and harden. The filler mimics wood completely once it has cured and hardened. It is easy to paint, sand, mill, stain, saw, and nail.
This is a wonderful resin kit to use for wood. Offering a long-lasting bond and with a high-strength formula the product allows a replacement for damaged wood. When the product has completely cured and dried it acts just like wood.
- Two-part epoxy to fill and repair rotted wood
- A permanent-bonding, high-performance epoxy compound
- Will not shrink, delaminate, crack, or crumble
PROS
CONS
- It can be difficult to get the texture out of the container before it has been mixed
- Quite an expensive product
Best Epoxy Putty: JB-WELD KwikWood Epoxy Putty
This brand is well known for producing adhesives that are high-strength. This two-part epoxy putty stick which is hand mixable is the ideal option for rebuilding and repairing wood. The product is designed to be used for household repairs and all types of wood. The bond is very strong at 900 PSI once the putty has been mixed. The product will maintain the same properties as wood when you stain it, saw it, or drill it. This epoxy filler won’t rot or shrink.
It is super easy to use and is ideal for any smaller DIY project. You can repair dents in the wood, holes, cracks, and even replace small pieces of missing wood. it is an easy-to-use product thanks in part to its super speedy drying time. However, as it is not a liquid you aren’t able to pour it into cracks and holes. That being said the putty texture is a great consistency for filling external wood damage.
- A hand mixable two-part epoxy putty stick to repair and rebuild wood
- Will not shrink or rot and can be stained, molded, sanded, and more
- J-B Weld delivers superior performance, quality, and results
PROS
CONS
- Can’t be used for internal filling as it is not a liquid epoxy
- Only good for smaller jobs as the putty is relatively small
Best General Epoxy Wood Filler: BONDO Home Solutions Wood Filler
If you are looking for a product that offers an easy wood fix, then this quick-to-use wood epoxy putty from Bondo is a top choice. This filler can make quick repairs to all types of decayed and rotted wood. You only have to wait 15 minutes for it to dry before you can sand it, and you can paint over it after only 25 minutes. It will be necessary to combine the two-part substance before you can begin using it.
You will get a permanent bond that can be used on outdoor and indoor items as it is water-resistant and durable. It acts like wood once it has cured and can be stained, sanded, and painted to look just like the original wood. You get a user-friendly, permanent, high-performance product from Bondo which can be used on an assortment of DIY home projects.
- Provides fast and durable repairs for damaged or rotted wood
- Fully sandable, stainable, and paintable
- A durable two-part epoxy solution for permanent repairs
PROS
CONS
- Your time to work with the product is limited as it dries so quickly
- It can be difficult to mix the filler correctly
How to Use Wood Epoxy Resin Filler
It’s time to get to work now that you know which products are the best. What follows are steps for using clear epoxy and wood epoxy putty to fill holes in wood. Follow our step-by-step for filling holes in wood with clear epoxy, and you will achieve perfect results.
Preparing the Wood
First things first – you need to get your wood prepared and cleaned. You can do this by removing any existing paint and caulk to expose only the wood. It might be necessary to use a paint stripper to ensure you have cleaned the wood thoroughly. Before applying any epoxy wood filler, you have to be certain the wood is dust-free and clean. Any oil, dirt, or dust left on the wood can impact the adhesive nature of the filler. Ensure that the wood isn’t bent or warped. This may cause the epoxy to freeze the wood into the wrong shape.
Apply an Epoxy Consolidant
The next step is to coat an epoxy consolidant across the whole surface that you will need to be filling. This substance is a thin form of epoxy that covers the wood fibers. This substance dries slowly, and we recommend you utilize it in conjunction with a wood epoxy putty. This coating assists with the overall adhesion and ensures a long-lasting wood filler bond. Once you have finished coating the wood’s surface with the consolidant, you will have to leave the wood for several hours to ensure it cures completely before you can continue.
Applying the Exterior Epoxy Wood Filler
Ensure the consolidant has completely cured before you start filling holes in wood with clear epoxy. Next, you will need to dam up or fill any of the cracks in the wood. You need to do this as the holes in the wood normally go further into the wood than you can see from the surface. Sometimes if the holes were made by insects, they may have created a network of tunnels that can extend right through the wood. If you fail to fill in or dam up the cracks the liquid wood filler may start dripping and running out of the cracks through these networks of tunnels.
You will have to use wood epoxy putty to do this. Combine the two-part epoxy filler forming a type of paste and then apply it to the holes and cracks on the wood. Use a plastic knife or a putty knife to smooth out the exterior epoxy wood filler. It’s not a problem if you do not achieve a perfect finish as this can be touched up and sanded down if necessary once it has cured. Just ensure the cracks have been sealed up sufficiently.
Pouring in the Liquid Wood Filler
Before continuing to the next step ensure the exterior wood epoxy filler has cured completely. Next, you can add the clear epoxy resin wood filler to its liquid state. Combine the resin wood filler to get a pourable consistency. Pour this mixture over the wood allowing it to flow into the insect tunnels and cracks. Even though you have filled up the large cracks and crevices to stop the substance from escaping, the holes and cracks remain open and allow the resin wood filler to flow in.
Slowly begin pouring the clear epoxy resin wood filler over the wood filling all the holes and cracks. Ensure you do this with care. When you have filled all the cracks all a few minutes for the filler to soak in completely. The epoxy may drop slightly. If so, pour over more. Repeat this process as many times as necessary until the epoxy has been absorbed into all the holes and cracks. To ensure the internal hole has all filled up you want to be certain the epoxy has completely penetrated the wood. This will ensure the wood can be held up with the necessary structure and support.
Finishing the Wood
At this stage the epoxy wood filler has successfully been applied. Before you begin finishing the wood, ensure that it has cured completely. The time the product takes to cure is dependent on the manufacturer and which product you have chosen to use. On average it takes around 24 hours to cure. You will be able to sand down the wood filler’s surface to achieve the right shape and level of smoothness once it has cured completely. You can use either an electric sander or sand it by hand.
You will be able to paint over the wood, or stain it, once you have finished sanding it. You will find the wood filler acts exactly like wood once it has dried. So, you will be able to drill, saw, and paint the wood just like you would have been able to do previously.
Tips and Tricks for Wood Epoxy Resin Filler
Depending on the type of wood and the circumstances the process of using epoxy wood filler may be slightly different. The above guide offers great steps to follow but occasionally you may be faced with unique scenarios with your DIY project. Try these great tips and tricks:
- Remove any decayed and rotted wood before you begin your project. You need to remove any wood that is soft and crumbling apart or is very wet. You can then use wood filler to fill in the gaps created
- Before starting your project make sure you are ready and prepared. Once the two-part epoxy has been sufficiently combined you only have a short period to work with it before it begins to cure. Make sure you are ready to start using it before you mix the epoxy and once mixed work quickly. Only mix the quantity you require. If there is any unmixed epoxy left over ensure you store it correctly and then it will last for a long time
- While the filler is curing either move the piece indoors or try to cover it to ensure dirt particles and dust don’t stick to the wet epoxy
- You may find a few remaining depressions in the wood when it has cured these can be fixed with ease using epoxy putty. Just apply the exterior epoxy wood filler once again over any cracks, holes, or dips that may still be there
- Due to the plastic-like structure of epoxy, it will take longer to sand it than the wood. Ensure you use a gentle sanding process be patient you may go through several sheets of sandpaper
- The temperature impacts the curing time of the epoxy. To get the best results, try working in a warm environment. You can apply a gentle source of heat over the epoxy to attempt to speed up the curing process
Frequently Asked Questions
Can You Screw Into Wood Filler?
You will be able to drill into the epoxy and add screws if necessary. Once cured, epoxy wood filler acts like wood.
Do You Need to Prime Epoxy Wood Filler Before Painting?
It may be a good idea to prime but it isn’t completely necessary. Filler and wood might react differently to paint being added, so primer across the whole surface will ensure the same type of adhesion over the whole piece of wood.
Is Epoxy Wood Filler Waterproof?
Epoxy wood filler is completely waterproof offering you a durable product. The filler can be used on both outdoor and indoor items.
How Long Should I Leave the Epoxy Wood Filler Before I Can Sand it?
Epoxy takes roughly 20 to 30 minutes to dry to touch. Rather wait at least 24 hours to ensure the epoxy has completely cured before attempting to sand it.
If you have damaged wood, epoxy wood filler is the ideal solution. It is a powerful product that assists you in not having to replace the wood in its entirety. We hope we have been able to equip you with all the information you need to work with epoxy wood filler.
