Safe Wood Cleaning Products

One thing we tend not to think about, when building wood projects, is keeping them clean. The finishes we apply provide a luxurious appearance, which we expect to stay forever. Yet as people use the things we’ve created, oils come off their skin onto the surface. Dirt mixes with this oil, forming a relatively solid coating. In cases where the wood is unfinished, this can stain the wood. But even in the case of wood that is finished this mixture of oil and dirt can fill the pores of the wood, especially on open grained woods.

Old wooden furniture and cabinetry will often be discolored from constant handling. Finish will be worn off along edges and corners that are handled frequently and the wood will be stained by this dirt and oil. This can be even worse in kitchens. Oil splattering and rising after being vaporized will settle on cabinets, especially those above the stove. While the buildup is imperceptible, over time it can drastically change the appearance of the original wood.

Likewise, wood floors can become discolored from dirt and oil. But in addition to that, they suffer the potential of damage by wear. Sufficient wear, combined with this dirt can permanently discolor the wood beneath.

None of this affects the function of the wood product, just its appearance. Nevertheless, proper care of wood products is essential to helping it retain its beauty through the years. So, just how can we do that?

There are a number of wood cleaning products on the market, as well as waxes and polishes. There are even some products which claim to provide “scratch cover” capability. Sorting through them and deciding which is the best can be challenging, especially as most of the information available is nothing more than manufacturer’s claims, not any true analysis.

To start with, there’s a huge difference between a wood cleaner, a polish and a scratch covering product:

• Wood cleaner – Intended for cleaning dirt and grime off of finished wood surfaces; basically a soap-based product. Most also contain solvents which will dissolve wax, although they are not supposed to harm varnish or lacquer. However, they can damage oil-based finishes, like Tung oil.
• Polish – Intended to restore the luster of the original finish, mostly by covering the varnish with a coating of wax. While it works well to make furniture look good, it will not remove that dirt, but rather cover it up, ensuring that it sticks to the finish.
• Restorer – Intended to hide bare wood, whether from scratching or wear. It does this by staining the bare wood to look like the surrounding finished wood. These are usually oil-based products, which will leave an oily film on the furniture until the oil dries. They do nothing to remove dirt and grime. 

One of the problems with using wood cleaners on damaged wood is that the exposed wood will soak up the water and swell, perhaps even become stained. It is necessary to take care to only get the wood damp and not soak it when cleaning. This is basically true for any wood cleaner you might use.

The Best Cleaner is Homemade

While any of those commercial products will work to get wood furniture clean, a homemade formula made of warm water, vinegar and dishwashing liquid actually works the best. There are a number of variants on this, but the basic idea is the same.

The basic solution is 50/50 vinegar and warm water. Put this in a spray bottle and spray the surface to be cleaned, allowing it to sit for a couple of minutes before wiping the solution off with a damp cloth. Avoid saturating the wood, as that might soak into the wood fiber. The vinegar works well for cutting through most dirt, leaving a clean surface. At the same time, it will not stain the wood.

This mixture works well for cleaning wood floors as well, especially if cleaning is needed before or instead of waxing. Floor waxes do not clean, so it’s a good idea to clean with vinegar and warm water, before waxing the floor.

For grimy cabinets, such as those over the kitchen stove, add a squirt of dishwashing liquid to this mix. Dishwashing liquid is especially good at bonding with grease, breaking it down. While normal soap could also be used, the dishwashing liquid is much easier.

Vinegar and Oil

Manufactures of some flooring products, especially composite wood flooring products, recommend avoiding the use of water on their flooring. In that case, a lightweight oil, such as cooking oil, can be substituted for water, making a mix of vinegar and oil. Make sure it is warm as well, as the warmth helps dissolve oily residue, which can then be carried away by the oil in the cleaner.

Some people add essential oils to the basic water and vinegar cleaner. This is done more to add the fragrant scent of the oil to the room than for any other reason. Those who believe in aromatherapy or who just like the scent of some of those oils may find this advantageous.

Lemon Juice and Hot Water

Lemon juice can be substituted for vinegar and mixed with water, in a 50/50 mix. Both vinegar and lemon juice are acidic, which is what helps them function as cleaners; so the results will be similar. The real advantage though, is that the room will smell better than it will if it is cleaned with vinegar.

What if that’s Not Enough?

There might be cases where those cleaning formulas and a rag aren’t enough to remove years of built-up grime. While it might be possible to scrub all the grime off, given enough time and elbow grease, there are easier ways to remove it, especially in flat surfaces.

Start with a narrow putty knife. Take it to the grinder and round the corners, smoothing them out with emery paper afterwards. Check it with a finger, to ensure there is no sharp edge or corner. That way, there’s less of a chance of scratching the woodwork, or even the finish, while trying to remove the grease and grime.

Wet the grimy areas with a combination of warm water, vinegar, and dishwashing liquid, as mentioned above. Allow it a couple of minutes to soak in, and then scrape off the softened grease with the putty knife, wiping it off onto a paper towel. Multiple applications may be needed, especially if the grime has been building up for years.

There may be places where the putty knife can’t be used, due to the curvature of molded edges cut into the edge of the wood. It might be possible to grind a putty knife to fit that curvature, but it is easier to do that with a plastic putty knife. The other advantage of the plastic one is that it is less likely to scratch the finish. Even so, it is possible that a custom ground scraper isn’t going to reach some difficult areas, especially if carving is involved. In those cases, use a soft Scotch-Brite pad. Care must be taken when doing this, as the Scotch-Brite pad may very well scratch the underlying finish. That’s why a soft pad should be used, rather than a stiffer one.

What if the Wood Finish is Damaged?

It is quite possible that older wood pieces, whether furniture, flooring or other pieces may have reached the point where the finish has worn or scratched away and the wood is exposed, perhaps even damaged. This can be repaired, but must be thought of more as a refinishing project, then just a cleaning project.

Nevertheless, the first step is cleaning off whatever dirt and wax is on the wood’s surface. Applying new finish to a dirty surface just seals in the dirt, making it permanent. Cleaning off the dirt may expose more of the bare wood, but that can be rectified.

Once the dirt is cleaned off, allow the wood to dry a full day, so that any water which has been absorbed into the wood can evaporate. If necessary sand the exposed wood. Do so gently, as the idea is to remove splinters, rather than to fully smooth out the surface. Part of the charm of old wood furniture is that the wear makes it look old. So it’s not advisable to try and smooth things out perfectly, as with a new project being built.

With the wood dry and sanded, apply stain or a restorer to the bare wood, bringing the color up to that of the finished wood. Don’t forget that the varnish will change the color slightly, yellowing and darkening it, so make allowance for that when staining.

Once the stain has dried, varnish can be applied. It’s best to varnish the entire piece, rather than just the damaged area, as the sheen will invariably be different. By varnishing the entire surface, people will not be able to tell where the original area ends and the repaired area starts.

It may be necessary to add wood filler to some portions that are severely damaged. Don’t do this until after applying at least one coat of varnish or sanding sealer. I’d recommend using a pre-tinted wood filler, possibly mixing different colors together to get an exact match. Smooth the wood filler into the wood with a finger, rather than a putty knife. This makes it easier to get a smooth finish that’s packed into the existing wood grain.

Before applying a second coat of varnish, sand the surface lightly with very fine sandpaper to remove any bumps in the finish, caused by sawdust getting into the varnish before it could dry. Do this between every coat, if multiple coats are used. If possible, do the finishing operations in an enclosed, dust free area, like a painting booth. If that is not available, a screened off area of the shop (screened off with simple shower curtains) can work rather effectively to protect the finish from floating dust in the air.

When refinish antique or even old furniture, a satin finish varnish is recommended, rather than a gloss finish. The satin finish will help hide the imperfections in the wood that have been caused by years of use and possible neglect. Gloss finishes tend to show every flaw and imperfection.

Taking that a step further, sanding the final coat of finish with extremely fine sandpaper, something like 600 grit or greater, will dull the finish, without leaving visible scratches. If not overdone, this can leave the luster of the finish, especially the depth of several coats of varnish, without the wood being shiny. That’s just about an ideal finish for most antique furniture, as it holds the antique appearance, without making the finished piece look either damaged or overly “shined up for show.”

For the best possible finish, buff the finish, polishing it after sanding it. This can be done with a clean buffing wheel, with jeweler’s rouge applied to the wheel or with wax applied. Each provides its own unique look, but all will help to give the piece that last little nudge, making it look perfect.

Disinfecting Wood

There are a large number of commercially manufactured products designed specifically for disinfecting wood and other furniture materials. Products which are certified for this must be registered with the EPA. Those which are deemed effective against COVID-19 are shown on the EPA List N. The product will have the registration number listed on the label, which allows users to check the product and how long it must have contact with the germs to be effective.

Take care when using some of these products on bare wood, as they can stain it. While Clorox Disinfectant Wipes are safe for finished wood, they are not recommended for use on unfinished wood surfaces. The same can be said for Lysol’s family of products.

While that is good, our original formulation of vinegar and warm water will work as a disinfectant as well. The acidic content of the vinegar is lethal to bacteria and viruses. If dish detergent is added, the soap will attack the fatty coating of the virus, causing it to break down. Once the fatty covering breaks down, the virus cannot survive.