What is Hardwax Oil Finish?

Hardwax oil is the secret weapon of furniture refinishers and restorers. This high-quality finish penetrates deep into the wood pores and accentuates the wood grain unlike any other topcoat.  It can mimic the vintage look of wood oils while requiring less maintenance. The oil soaks into the wood, highlighting the wood grain while the waxes sit on top of the wood and harden into a protective finish.  The finish results in a natural look, smooth to the touch and moisture resistant.

Hardwax Oil Ingredients

Each brand of hardwax oil has a slightly different ingredient list, however, the general method is a blend of natural oils and waxes with a small number of solvents.  The solvents help to speed up the general drying time.

The typical oils used are Tung Oil, Linseed Oil, Sunflower or Thistle Oils and the waxes added could be Carnauba wax or Bees wax. Together these natural ingredients when blended produces a product that is a favourite for furniture, cutting boards, wooden floors and more.

The solvents added can lead to levels of high VOC (volatile organic compounds) within the product, so check the variety you purchase for the level of VOC. Furthermore, if you plan to use the product for items which will come in contact with food, check if the brand of hardwax oil is food safe. The food safety usually only occurs once fully cured and all solvents have evaporated.

Benefits of Using Hardwax Oil

With such a large variety of finishes available on the market, it can be confusing to know what finish is right for your project.  Hardwax oil offers benefits that makes it popular with furniture specialists:

Enhances the wood grain – Unlike finishes that sit on top of the wood, hardwax oil penetrates deep into the pores to highlight the natural beauty of the wood. In this manner it is like a traditional oil finish. It provides a rich, saturated look that brings out the depth of the grain patterns.

Allows the wood to breath – Hardwax oil will not trap moisture inside the wood like film finishes can. It soaks into the surface while allowing airflow and evaporation. This prevents cracking, warping or cupping of the wood over time.

Durable protection – Once cured, hardwax oil forms a protective barrier that is water-repellent and stain-resistant. It helps guard against scratches, scuffs, and liquid spills while retaining the natural feel of the wood. Some Hardwax oil also contain UV inhibitors to help protect surfaces from sun damage and fading. The finish is easy to maintain by applying fresh coats as needed over time.

TIP: Water-repellent is not water resistant. I recommend to still use coasters to protect the finish from developing water rings.

How to Apply Hardwax Oil

Applying hardwax oil finish to wood furniture is a simple process that usually only requires a few thin coats. Here are the basic steps:

Prepare the wood surface – Make sure the wood is clean, dry, and sanded smooth. Remove any dust, dirt, wax or oils from the surface. Lightly sand with 220 or 240 grit sandpaper before applying the oil.

Apply a thin coat – Use a clean lint-free cloth or high-quality brush to wipe a thin layer of hardwax oil onto the wood. Apply in the direction of the wood grain to minimize any brush strokes. A single application can already make the wood grain pop. You may wish to work in sections rather than applying over the entire surface, depending on the drying time.

Allow to dry – It is important to read the dry time for the product on the instructions.  Each brand has different drying times.  Allow the recommended drying time, before removing the excess oil.

Remove excess – Wipe away any excess oil that has not absorbed into the wood. Buff lightly with a clean, dry cotton cloth after the recommended drying time.

Apply additional coats – For best protection, apply 2-3 thin coats of hardwax oil, drying between coats.

Allow to cure – Let the final coat cure at least 24 hours before use. Curing may take longer in cold temperatures. The general sheen is a matte finish, unless the version of hardwax oil is specially formulated for a glossy finish.

Maintenance of Hardwax Oil

Hardwax oil finishes will require maintenance to keep the wood surfaces looking their best. Here are tips:

Periodic Reapplication – Hardwax oils do not last forever, especially on high traffic surfaces. Expect to reapply a fresh coat every 1-2 years for high-traffic surfaces like tables and countertops, and every 2-4 years for surfaces that get less wear like shelves or side tables. Simply clean the surface, lightly sand to degloss, vacuum up dust, and apply a new thin coat of hardwax oil.

Cleaning Methods – For day-to-day cleaning, simply wipe down hardwax oiled surfaces with a damp microfiber cloth and mild soap if needed. Avoid abrasive cleaners or scrub brushes/pads which can damage the finish over time. For deeper cleaning, use a degreasing agent like citrus solvent and reapply a maintenance coat of hardwax oil after cleaning.

Hardwax oil is easy to refresh and maintain – just remember to reapply fresh coats periodically to keep your wood looking its best! Proper cleaning methods will also help maximize the life of your finish.

Compare to Other Finishes

Hardwax oil has advantages and disadvantages compared to other common wood finishes like tung oil, Danish oil, and polyurethane.

Vs. Tung Oil – Tung oil penetrates wood deeper which provides protection inside the wood pores but not as well on the surface. Tung oil takes much longer to cure – up to 4-5 days between coats. It also does not create as hard of a surface coating as hardwax oil.

Vs. Danish Oil – Danish oil is a blend of oils and varnish that cures faster than tung oil. But Danish oil does not penetrate as deeply into the wood or create as protective of a coating as hardwax. Danish oil also requires more maintenance over time. Historically, Danish oil is the oil used on vintage teak furniture.

Vs. Polyurethane – Polyurethane forms a plastic-like coating on top of the wood that is thicker and more protective than hardwax oil. Polyurethane can give the wood a “plastic” or coated look vs. the natural finish of hardwax oil or other wood oils. Polyurethane finish is available in both water based and oil-based versions. Polyurethane also will not enhance the wood grain.

Safety Tips When Using Hardwax Oil

The solvents in this product can be irritating to the eyes, skin, and respiratory system. Check the VOC levels on the can and take the following safety precautions:

Ventilation – Work in a well-ventilated area when applying hardwax oil. Avoid breathing in vapours released by the oil and use a respirator.

Skin contact – Wear gloves when handling and prevent skin contact. Immediately wash off any oil that gets on your skin with warm water and soap.

Eye protection – Wear safety goggles or glasses when applying this finish to protect your eyes. If the oil gets in your eyes, flush at once with water and seek medical attention for the solvents used in the product.

Flammability – Hardwax oil is flammable while wet. Avoid open flames during application and drying. Allow proper ventilation during the drying process. I also place my rags for buffing and wiping excess hard wax oil, in a bucket of water to avoid any potential fire starting. Better safe than sorry.

Final Thoughts

Hardwax oil is a must for your refinishing kit for when you wish to create a vintage look and accentuate the wood grain.  Its finish provides a protective coating that is more durable than wax finishes or oil finishes alone.  This type of finish is simple to add and easy to maintain for customers.

I have personally used two types of hardwax oil, from Osmo and OLI NATURA Öle & Wachse, both German brands.  Osmo comes in a variety of sheens from matte to glossy.  The version from Oli Natura is a standard, vintage matte sheen level. Rubio Monocoat, General Finishes and Fiddes also produce popular versions of this finish. Test out which brand works well for you and the look you wish to achieve.