What grit sandpaper do you use between coats of polyurethane?

Asked By: Damyan Zurfluh | Last Updated: 3rd April, 2020
Category: hobbies and interests woodworking
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Sand lightly with 240-grit sandpaper between coats, then let the last coat dry for at least 24 hours. This is standard practice with any wood finishing job, and is nothing out of the ordinary. That said, sanding bare wood beforehand to create a smooth foundation is key.

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Then, do you have to sand in between coats of polyurethane?

A: There's no need to sand between coats of finish if you apply each coat within the recommended amount of time. However, you might want to sand lightly before the final coat just to make sure the last coat goes on smoothly.

Secondly, how do I get a smooth finish with polyurethane? How to Get a Smooth Polyurethane Finish

  1. Overview: Materials and techniques.
  2. Tip 1: Sand out pencil marks.
  3. Tip 2: Maintain a clean work area.
  4. Tip 3: Wipe the project with mineral spirits.
  5. Tip 4: Use a roller on large, flat surfaces.
  6. Tip 5: Finish both sides at once.
  7. Tip 6: Use wipe on poly for small or tight areas.
  8. Tip 7: Lightly sand with pads and paper.

Also to know, do you sand the final coat of polyurethane?

No, you don't sand the final coat. You make sure you either spray it, or lay it on nice and even. Sand the previous coats to make sure there is a perfectly flat and even base for the final coat.

How do I apply a second coat of polyurethane?

Issue sanding between coats of polyurethane

  1. Apply a THIN coat of Minwax® Fast-Drying Polyurethane using a high-quality natural or foam brush.
  2. Let dry 4-6 hours. Then lightly sand entire surface with fine sandpaper (220 grit) to ensure an even finish and proper adhesion.
  3. Apply second coat. If third coat is desired, repeat step 5 before application.

36 Related Question Answers Found

What happens if I don't sand between coats of polyurethane?

MYTH #7: Scuff sand between coats to get a good bond. The purpose of this instruction is to create scratches in the surface so the next coat of finish can establish a “mechanical” bond. Polyurethane dries slowly, so there are always dust nibs that should be sanded out before the next coat is applied.

Can you put too many coats of polyurethane?

Too many coats of poly has potential to bulge unless applied to both sides. Wood breaths, even through poly. Ambient moisture being exhausted deferentially through one side of the wood can cause problems.

How do you apply polyurethane without brush marks?

A light coating of finish after sanding disguises the area.
  1. Sand down the brush marks lightly with the fine-grit sandpaper.
  2. Brush the sanded area off with a soft cloth to remove all traces of dirt and grit from the sanding.
  3. Apply the polyurethane finish lightly to the brush, making sure to wipe off any extra.

How do you know if polyurethane is dry?

There are several ways to determine whether a surface is dry: OIL BASED products are dry if they are no longer tacky and do not emit a smell. WATER BASED products are try if they no longer feel cool to the touch and a powder will form with light sanding.

What grit sandpaper do I use between coats of polyurethane?


Sand lightly with 240-grit sandpaper between coats, then let the last coat dry for at least 24 hours. This is standard practice with any wood finishing job, and is nothing out of the ordinary. That said, sanding bare wood beforehand to create a smooth foundation is key.

Why is my polyurethane rough?

If you put polyurethane on a rough surface you will get a rough finish. Second, as @keshlam says, make sure there is no dust at all on the surface before you apply the finish. If you keep re-brushing over the finish as it gets tacky you will leave the surface rough.

How long should polyurethane dry between coats?

In-between Coats
When applying polyurethane, brush along the grain, stretching the polyurethane into as thin a coat as possible. Always allow polyurethane to dry 24 to 48 hours before sanding, to give the surface time to cure and harden.

Is 1 coat of polyurethane enough?

One coat of Polyurethane is not often enough to ensure a truly beautiful finish on your wood projects. Multiple are needed to provide plenty of protectant and keep your wood looking gorgeous. Steps for Applying Polyurethane for a Beautiful Finish: Sand down the wood.

Can you apply polyurethane with a rag?

Applying Polyurethane for a Durable, Beautiful Finish. Polyurethane is widely revered as one of the most durable yet easy-to-apply protective wood finishes. Standard polyurethane is applied with a brush, but there are also wipe-on formulas that are applied with a rag, as well as a spray finishes in aerosol cans.

What happens if you apply polyurethane before stain is dry?


If you apply poly before the stain is adequately dry, you're going to end up with stain mixing into your poly, poly that takes forever to dry, or worse. In some cases, applying poly over wet stain can reduce the bonding ability of the poly, which will end up ruining your finish over time.

Can you roll on polyurethane?

Yes, you can use a paint roller to apply polyurethane. Polyurethane is easily applied with a paint brush or roller and dries quickly. Applying the material with a roller eliminates brush strokes and lines and prevents over-applying the material.

Can you rub out polyurethane finish?

You can rub out all types of film forming finishes, including shellac, lacquer, oil based varnish and polyurethane, waterbased coatings and catalyzed or conversion coatings.

How do you make a matte finish with polyurethane?

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.

Can you wet sand and buff polyurethane?

Place a rubber sanding block with 320-grit wet/dry sandpaper on it into the pan. Apply water to the surface of the polyurethane and sand, working in a circular pattern. Wipe the surface with a clean cloth every so often to gauge progress. Work until the surface has an equal dull haze to it.

How do you remove dust after sanding polyurethane?


If you want the smoothest finish possible, then wait until it is dry, very lightly sand with very fine paper (220 or finer) to remove any dust bumps, wipe it clean with a slightly damp cloth or tact rag, let it dry or buff it dry with a dry cloth, then apply the next coat.

Do you sand after final coat of Polycrylic?

Should Polycrylic™ be sanded between coats? Yes. A light sanding (#220 sandpaper) will remove any fine particles of dust which settle on the finish while it is still wet.

Why am I getting bubbles in my polyurethane?

The concept behind thinning the first coat is to fill some of the unseen or unfelt pores in the sanded wood. If polyurethane is thinned, it will seep into the undetected pores much easier than unthinned poly. If the wood has not been sufficiently sanded, it could show up as air bubbles.