Solid wood can be pretty expensive, which is why there are alternatives like engineered boards. Plywood on the other hand is an engineered board that is basically slim sheets of wood, glued together in an alternate grain pattern. While this makes it pretty durable compared to something like MDF, it also retains the qualities of wood. While you cannot finish an MDF board that is laminated, you can definitely finish a plywood board with oil. However, which oil is the most suitable for plywood boards? In this article, we will find out just that and explore what kind of oil finish is best for plywood.
Tung oil and boiled linseed oil are the best oil finishes for plywood. Plywood is mostly made out of various solid wood veneers. So it can be hard to choose one kind of oil for plywood. Because every wood reacts differently to different finishes. However, since tung oil and boiled linseed oil are safe choices to use for most solid woods, they can be considered the best for plywood too. Both these oil finishes are non-toxic, and do not contain any chemicals that might damage the plywood, and get absorbed by it.
Depending on the type of wood used in the plywood, you can change the finish to best suit it. In most cases though, you don’t even know which wood has been used in it. Not to mention most plywoods have multiple wood types used in the mix. So using neutral finishes that are safe in most cases is the best option. Natural oil finishes like tung oil and boiled linseed oil are used by woodworkers on any wood. This makes them the ideal choice for the finish on something like plywood.
Best Oils for Plywood Boards
1. Tung Oil
Tung oil in its natural form can be considered the best natural finish and has remarkable qualities. Some woodworkers consider raw tung oil as one of the best finishes comparable to some synthetic clear coats like polyurethane. It is a penetrating oil that is absorbed by the fibres of wood and hardens as it dries and cures. This helps protect the wood and also rejuvenates it, giving old dried wood new life. In the case of plywood, it will not damage the veneers that are glued together but strengthen the fibres and give it a beautiful natural look.
Tung oil is the main component in many oil-based finishes, just speaking volumes of its qualities as a finish. With plywood, not just any oil-based finish will do since we don’t know the wood we are working with. So natural tung oil, with all its qualities, is the best option to give your plywood a beautiful natural look. It will accentuate the grain pattern of the plywood and strengthen it from the inside out. As the oil hardens it will also make the plywood water-resistant.
Hope’s 100% Natural Tung oil at the moment is one of the best products and has positive reviews by most woodworkers across the region. It dries fast compared to most oil finishes, it penetrates deep into the wood and makes it moisture-resistant. Lastly, it is food-safe and non-toxic once it dries, contains no VOCs and is safe for the environment.
2. Linseed Oil
BLO or boiled linseed oil is a classical finish that works on woods globally. If someone does not have an idea of how to finish the project they are working on, then you can bet that the safest choice to go with is linseed oil. It has been used by woodworkers throughout the ages as it gives wood new life and accentuates its colour along with the grain pattern. For something like plywood where we usually don’t know which woods are used in its making, linseed oil will be a great option.
Plywood is not as strong as normal wood, applying linseed oil can help it be more durable as it penetrates into the fibres of the wooden veneers, and hardens. One drawback of linseed oil is that it takes too long to dry, even more than tung oil. Boiled or polymerized linseed oil dries faster than its raw form, but even then it takes double the time as other drying oils. Though the best part is how safe boiled linseed oil is. It is the best finish for children’s furniture made out of plywood since it does not have any toxic substances. It does have a smell to it during its drying phase, but once dried, it does not have a strong odour.
Right now there are many brands that are selling boiled linseed oil for wood. However, the Furniture Clinic Boiled Linseed oil is by far the best choice for plywood and wood alike.
Step-by-Step Guide on Oiling Plywood
Since plywood is sheets of wood veneer, it acts just like normal wood does. This means that when you are planning on applying any finish to plywood, you will need to prepare it like you prep wood normally.
Step 1 – Sanding the Plywood
To sand plywood use a random orbit sander, you don’t need to sand it by hand. This is because wooden veneers are placed in alternate grain directions. Start sanding from 80-grits, make sure you cover the entire surface of the plywood thoroughly. Once you are sure that you have sanded the plywood with the 80-grits, move to 120. Take your time to sand as you don’t want to leave any unsanded spots. Once you are finished with 120, go up to 150, then 180-grits.
As you go finer, you will have to sand more thoroughly as the abrasive gets less coarse and removes less material. If you want to stop here, you can, but you can go up to 220-grits if you want smoother results.
Step 2 – Oiling the Plywood (First Coat)
Wipe the plywood clean so there is no dust on it as it can impede the oiling process. Not to mention it will waste the oil too since dust mixes with it and becomes a slurry. Wood cannot absorb this thickened oil, so it ends up getting wasted. So just clean the plywood thoroughly and apply the first coat of oil by pouring it liberally on a rag or the surface of the plywood. Use a clean rag to spread the oil evenly on the board and make sure to cover every inch of it.
Wait an hour after which you wipe off the excess oil that remains unabsorbed and is sitting on top of the plywood.
Step 3 – Applying Second Coat
Most people will stop at the first coat since they are mostly going to apply a clear coat over their plywood for extra durability. However, applying a few coats is necessary if you want to ensure that your plywood is fully saturated with oils. Apply the second coat of oil using a clean rag and use it sparingly as the plywood has already absorbed plenty of oil. You are just making sure to saturate it by applying more coats.
Step 4 – Curing
Once your coats of oils have been applied and dried, take a clean rag and wipe off any excess oil that remains on top of it. Now it is time to let the oil cure the plywood. It might take a week or two depending on the curing time of the oil. You can check the manufacturer’s instructions if you are unsure about how long to let it cure. Though two weeks is the safest bet as most oil finishes will cure by then.
Benefits of Oiling Plywood
Plywood is a durable material, but not as durable as normal wood. Solid wood is pretty dense, it also has qualities like water resistance and such. Plywood on the other hand might not have the same qualities as the woods used in it. This is because the wood is not dense, instead, they are just shaved off veneers of the wood. So oiling plywood will give it more strength, more durability, and even some degree of water resistance. Not only that, but it will also bring out the natural look of wood by accentuating the grain and the colour of the board.
FAQs – Frequently Asked Questions
Can I use OSMO Polyx Hard Wax Oil on plywood?
Yes, you can use OSMO Polyx Hard Wax oil on plywood as it will not only protect the wood from the inside with the vegetable oils but also harden the top with the carnauba wax. It will protect the wood from the inside out with the ingredients present in it.
How to make shiny plywood finish?
You can use the wet and dry sandpaper method by sanding in between the layers of oil to make the plywood shiny using only an oil finish. Of course, you can always use a clear coat finish that gives the wood a glossy and shiny look on top if you don’t want to go through all the grits of sandpaper since it will take you at least 480 grits to achieve a satin sheen.
Can you apply oils with stains to darken plywood?
Yes, if your plywood is very light in colour, you can always use oil with dyes and stains in it. Darker tung oil also works great in that aspect as it contains some dyes and stains it to darken the wood.
Plywood is a great material to work with if you are short on budget. It is durable, and very inexpensive compared to solid wood. By applying a few layers of a good oil finish, like the ones we have mentioned above, you can achieve great results and give plywood a look almost similar to that of normal wooden boards.