Apply only one thin coat. Then, remove any dust nibs with 1,500-grit sandpaper or a piece of brown paper bag. Finally, using a soft cotton rag or polishing pad, buff the finish to a high shine using automotive paste wax, photo below, which has fine abrasives that polish the finish even further.
How to use water based polyurethane without brush marks ! Sand your surface in successively finer grits down to 220 grit with a random orbital sander. Spray the surface with water and allow it to dry. Sand your surface to 220 grit with a random orbital sander, to remove the raised grain. Open the can of water based polyurethane .
Apply polyurethane using a bristle or foam brush about 2″ wide. Foam works well and eliminates the chore of cleaning , because the brushes are cheap and thus disposable. You can apply the first coat full strength or thinned up to half with paint thinner, making, in effect, a wiping varnish.
Failing to sand between coats of polyurethane does not have a significant impact on the finish. Even so, I still advise that you sand between the coats when applying polyurethane as this will help increase the adhesion between the layers to give you a more level finish.
*How Do I Remove Brush Strokes from the 3rd Coat of High Performance Polyurethane ? Sand down the final finish with a 220-grit foam sanding pad, and then add another layer of General Finishes High Performance PolyurethaneTopcoat. Apply liberally than you did previously without heavy back-brushing.
Use a blow torch . I do not recommend using a blowtorch on wet oil-based polyurethane . Unless you ‘re going for that smokey look, of course. This is a good technique for epoxy and probably water based poly, though.
Polyurethane is so durable and water-resistant, it has largely replaced shellac and varnish as a wood finish. Originally, it had to be brushed on, but different formulations mean it can now be applied as a spray or by wiping it on with a rag .
Clean off the surface with a damp rag see if there is an even surface, If the poly is thick, you can sand again and if it not, then add another coat of poly. Now, work your way up the grits and check the surface to see if there is an even sheen. If you like the sheen level, you can stop and buff it with wax.
Hand Rub With Wipe-On Varnish or Oil If you want to transform the sheen from high gloss to satin or matte, then using a hardening oil such as tung oil is a good way to do it. Apply a base coat of gloss water- or oil-based polyurethane , let it dry and scuff it with 220-grit wet/dry sandpaper. Apply a second coat.
Soak your brush in water(for water-based polyurethane ) or mineral oils (for oil-based polyurethane ). Soaking the brush also softens the bristles to make your application even better. Let the brush soak until air bubbles stop coming out from the ferrule, then remove the brush and gently wring out the solvent.
Oil-based polyurethane is very durable, making it the best choice for finishing wooden floors or furniture that gets a lot of use, such as a kitchen table. Polycrylic is a water-based product that is far less smelly and toxic than either type of polyurethane , making it easier to work with.
Use natural bristle for oil-based finishes and synthetic filament (polyester, nylon, or a blend of the two) for water-based and water-based oil-modified finishes. Don’t use rollers or foam brushes —they create bubbles.