To seal wood properly first prepare the surface by sanding it smooth and, if you like, staining it a color. Then you can apply a sealant, but there are many to choose from. The three most common sealants are polyurethane, shellac, and lacquer, and each requires a different method of application.
Paint Or Seal Unfinished Furniture
Bare wood, when left unfinished, keeps your furniture with a natural wood look but the risk is exposing it to harsh elements, even if it's indoors, such as light, dust, moisture and water damage, making it more susceptible to stains, warping and cracking.
Polyurethane wood finishes are synthetic coatings that are highly durable and water resistant, making them the best clear coat for wood protection.
There are three types of clear topcoats used to seal natural wood or bleached furniture – polyurethane, polycrylic, and wax finishes.
All unfinished wood or bare wood surfaces should always be primed prior to painting. This goes for both interior and exterior paint projects. The reason you cannot skip bare wood priming is that wood is porous and has a grainy surface. Because primer contains high solids, it helps fill grains in the new wood.
Thompson's Water Seal
This is why in most woodworking blogs, their water seal always tops the list of recommended wood sealers. Aside from resisting most types of mold and mildew, it's also long-lasting. So you won't have to worry about reapplying a sealer every couple of years.
If you leave furniture raw without applying a new coat of wax or poly you are taking a risk of your furniture drying out, cracking, swelling or staining. To limit wood damage, preserve furniture AND keep it looking natural you'll want to seal raw wood with Liming or Cerusing wax.
Tung oil is often recommended as a sealing oil for furniture because it protects the wood from moisture and stains.
Clear finish can be applied over stain or directly to raw wood. It's an extra step, but it's always worth the time.
Yes! A polyurethane wood finish looks beautiful and is one of the most durable top coats for wood finishes. It works great on stained wood, raw wood, weathered wood finishes, and painted wood finishes too.
Wood can be left unfinished if it won't encounter weather, water or significant handling. If your project is placed outside, will be somewhere wet, or will be used on a regular basis, then you should apply wood finish.
Which is better: polyurethane or polycrylic? Polyurethane is better for durability, but polycrylic is better for interior surfaces like cabinets, furniture, and trim. However, for light painted furniture and cabinets, polycyrlic is preferred because it doesn't yellow on the surface.
Natural Oil Wood Finishes. Linseed, tung, refined hemp, soy, and walnut oil are all-natural oils that on their own can be used to seal and protect wood. They are called drying oils. Drying oils penetrate, harden and preserve wood – providing a long-lasting finish that does not turn rancid.
Sealers are different from oils because they do not “feed” the wood more oils or resins. Instead, they seal in the oils and resins that the existing wood contains while at the same time preventing contaminants and moisture from harming it. Sealer does need to be reapplied nearly as often as oil.
Tung oil creates a harder, more durable finish than linseed oil. Tung oil is more water-resistant than linseed oil. Raw linseed oil takes significantly longer to cure than pure tung oil. Tung oil is generally more expensive than linseed oil.
It can be used to treat several kinds of wooden surfaces. From chairs and tables to wooden storage boxes, you can use olive oil and let it act as a varnish. Although olive oil does not have the same thickness as the varnish coating has, it can protect woods from mild dents and scratches.
To make wood waterproof naturally, use either polymerized linseed oil or tung oil, which are the two best natural wood waterproofing products. Refined hemp oil and walnut oil can also be used, but you will have to apply a repeat coat more quickly.
Oil and Vinegar
And, believe it or not, a bit of canola oil (3 parts) and vinegar (1 part) makes a dandy wood sealant, protecting wood from borrowing insects, wear, and water. Plus, this can be reapplied to revitalize the wood, something that doesn't work without sanding off the varnish.
Marine spar varnish is the best type for outdoor use. Its key ingredients are linseed oil (pressed from flax seeds) and alkyd resin (made by reacting linseed oil with alcohol and acid). The film is flexible enough to move with wood as it shrinks and swells with shifts in humidity.
Oil-based primers are ideal for interior and exterior unfinished or bare wood because they seal the porous surface of wood, enabling the coat of paint to better cover the surface. They stop tannins, released from woods, such as cedar or redwood, from bleeding through the surface of the paint.
If you do not seal with a primer, you can generally expect the first coat of paint to be blotchy, this is due to the fact that wood absorbs paint rather easily. In addition, the water that is found in the paint will cause the grain to raise, especially around knots.
If you're painting wood without a stain or finish, use a latex or an oil-based primer for the best results. Don't over or under apply the primer: You should aim to apply two coats of primer to your wood's surface. Brush the primer on, and allow the first coat to dry completely before adding the second coat.
Polycrylic is not as durable as polyurethane and is meant to be used only on interior surfaces such as cabinets, furniture, and trim. It shouldn't be used in exterior applications or on surfaces that are subject to lots of wear, such as floors, or that are exposed to water.