At 50% relative humidity and 70°F, Interior Oil-Based Polyurethane will dry to touch in 3 hours. Under ideal drying conditions, allow 6 hours before recoating. Overnight drying is recommended. Drying time will be affected by temperature, humidity and film thickness.
Wait at least 24 hours before light use of the surface and 48 hours before placing furniture on it. Water-based polyurethane is becoming increasingly popular due to its faster drying time and low odor.
How Long Does It Take For Polyurethane To Dry? After application, oil-based urethanes take about 24 hours to dry, while water-based urethanes require six hours of dry time. However, there's a significant difference between dry time and cure time.
A finish that remains tacky long after the expected drying time may be due to poor preparation, inadequate drying time between coats, or high humidity. To address this: Allow more drying time in a well-ventilated area. If tackiness persists, lightly scrub the surface with steel wool.
The average dry time for water-based finishes is 2 to 8 hours while other urethanes dry between 4 to 24 hours. It is safe to lightly walk on the floor the day after we put on the last coat of finish however, we recommend waiting at least 24 hours before placing any furniture.
Tips for Professional Results. Apply 1 to 2 coats of stain when using a brush and 2 to 3 coats if you're spraying the polyurethane.
Single Component Water Based Polyurethane Dry Times
It can take as little as 4 hours for the finish to dry and 8 hours for the fumes to dissipate. It's recommended that you stay out of your home for at least 8 hours after applying a water-based polyurethane finish, though usually, you can walk on it much sooner.
In a bowl or dish, mix vinegar and water in a 1:1 ratio. This solution will help to remove any sticky residue from the surface of your table.
There are two ways to tell if it is an oil-based product is dry. If it is no longer tacky and it doesn't smell, it is dry. You can tell if a water-based product is dry by touching it. If its cool to the touch, it's not dry.
Most of the time, residual stickiness will resolve itself but depending on thickness and condition of the coating, it may take an impractically long period of time. (Just maintaining a dust-free surface for more than a few hours can be challenging.)
Two coats of finish are suggested for most interior projects. When sealing floors, you should apply three coats. However, do not apply more than two coats in one day. 220 grit sandpaper should be used between coats to remove any air bubbles, but avoid using steel wool.
Polyurethane will dry to touch in 3 hours. Under ideal drying conditions, allow 6 hours before recoating. Overnight drying is recommended.
Coat the entirety of your workpiece, but don't brush excessively or you'll create areas with too little polyurethane. Allow each coat to dry fully. To give the subsequent poly layers something to bond to, sand lightly between coats with 320-grit sandpaper wrapped around a hard block.
Coat the underside
Wood absorbs moisture from the air, shrinking and swelling with changes in humidity. Polyurethane (or any coating) slows that absorption. So if you coat only the topside, the unfinished underside will shrink or swell at a different rate. That means a warped table.
You should use an automotive polishing compound and a buffer for big areas. Small areas will have to be polished by hand unless you have some funky buffing tools. Make sure the poly has cured for a minimum of 4-5 days at 70f. Do not try to polish an uncured film.
It's all about adhesion. When you recoat after 2 hours you get a chemical bond between layers. If you let it go longer than that, you need to wait 24 hours so it's hard enough to sand and get a mechanical bond.
The more coats you apply, the smoother it usually gets as well. Ultimately at least two coats on the top is preferable unless you want a very rough feel to the finished product.
Surfaces finished with oil-based polyurethanes can be used after around 4 days, but full cure normally takes 30 days.
Summary Comparison of Water based vs Oil Based Polyurethane:
water based: doesn't change color of wood, dries clear and stays clear. Ideal for light colored wood. oil based: darkens the color of wood adding yellowish tone, amber tone continues to darken over time.
Your sticky problem is more than likely caused by the finish itself failing. Drying oils in the varnishes eventually destroy themselves and the sticky surface you describe is the result. Lacquers can suffer a problem caused by plasticizers migrating through the resins. One way or another, your finish surface is done.
Pour the acetone onto the surface or apply it with a brush. Wait 10 to 15 minutes for the acetone to soften the polyurethane. If necessary, scrape the polyurethane away with a putty knife or scraper. Wipe the surface clean with a dry cloth.
Waterborne polyurethanes usually require a minimum of 3-4 coats to be effective. Although there is some evidence that too many coats can result in a plastic-like finish, waterborne polyesters are thinner than other types and therefore require several more coats to provide the same protection for hardwood floors.
Oil-based polyurethane often dries more slowly than its water-based cousin. It's best to wait at least 24 hours before wearing socks and walking on the floors. Full Cure: It's advised to wait at least 72 hours before moving furniture back in, even if you might be able to walk on the flooring after just one day.
One of the primary concerns with PU leather is its tendency to peel or crack over time, especially with frequent use. The polyurethane layer on top of the backing material can begin to break down, which can cause the material to become brittle and start peeling.