How to Sand Down Edges of Quartz Countertops

Sanding down the edges of quartz countertops is an important finishing step to help smooth any rough spots and create a clean, polished look. With some basic tools and techniques, you can achieve professional-looking results.


Quartz countertops are an increasingly popular option for kitchen and bathroom remodeling projects. Made from ground natural quartz combined with resins and pigments, these engineered stone slabs are prized for their durability, low maintenance, and custom appearance.

However, the fabrication process can sometimes leave small chips, uneven spots, or noticeable seams on the edges that detract from the countertop’s finished look. Thankfully, it’s possible to smooth and polish the edges yourself with some simple sanding techniques.

Properly sanding the edges will help:

  • Remove any small chips or uneven spots
  • Blend seams between quartz slabs for a seamless look
  • Soften sharp corners into a more finished rounded profile
  • Create an ultra-smooth surface and sheen

With the right tools and methods, DIYers can achieve results comparable to professional fabricators. This article will cover everything you need to know to sand down the edges of quartz countertops yourself.

What You’ll Need

Sanding quartz countertop edges doesn’t require specialized tools. Here’s a look at the basic supplies you’ll need:

  • Orbital sander – A random orbital sander with variable speed settings allows you to smooth the edges efficiently. Models that accept Velcro-backed sanding discs tend to work best.
  • Adhesive-backed sanding discs – Discs in grits from 50 to 3000 are ideal for gradually smoothing and polishing the edges. Choose discs specifically designed for stone.
  • Soft sanding sponge – For hand-sanding fine details, a flexible sponge can contour to rounded edges. Look for sponges in 220 grit or higher.
  • Masking tape – To protect the surface of the countertop, tape off the area around the edges you’ll be sanding.
  • Ear and eye protection – Wear safety glasses and ear plugs or muffs when operating the sander.
  • Dust mask – A N95 mask will filter fine quartz dust produced during sanding.
  • Isopropyl alcohol – For cleaning sanded areas, apply alcohol on a cloth to remove residue.

Sanding Technique

With the right supplies gathered, you can begin smoothing the edges using the following technique:

Step 1 – Prepare the Edges

First, thoroughly clean the countertop edges you wish to sand using isopropyl alcohol. Allow the surface to fully dry. Then, tape off the top surface of the countertop several inches back from the edges. This protects the surface from accidental sanding and keeps dust away.

Step 2 – Use a Coarse Grit Disc

Attach a 50 or 60 grit adhesive sanding disc to your orbital sander. These coarse grits will remove the most material efficiently. Turn the sander on low speed and gently smooth the entire length of the edges, working from one end of the countertop to the other.

Apply even pressure and keep the sander moving constantly to avoid uneven sanding. Work carefully around corners or seams. After fully sanding all edges, wipe away dust with alcohol and a clean cloth.

Step 3 – Step Up Through Finer Grits

Next, swap the coarse disc for a finer 80 or 120 grit disc. Repeat the sanding process to smooth the edges, removing deeper scratches left by the previous grit. You can then step up through even finer grits—180, 240, 400, 600, etc.—until the edges feel ultra-smooth.

Take time with each progressive grit to eliminate all scratch marks before moving to the next. Wipe the edges frequently with a clean cloth to inspect your progress.

Step 4 – Hand Sand with a Sponge

For hard-to-reach spots like inside corners, use a flexible sanding sponge. A 220 or 400 sponge can smooth out tight radii and seams. Apply light, smooth pressure with the sponge as needed to blend imperfections. Avoid staying in one place too long.

Step 5 – Final Polishing

After sanding up to your finest grit on the sander, finish by hand polishing with a 3000 grit wet sanding sponge. Use a spray bottle to mist the edges with water. Rub the sponge gently in small circles to create an ultra-smooth polished finish. Wipe dry and inspect the edges—they should now have a glossy sheen.

Sanding Tips

Follow these tips when sanding quartz edges for the best results:

  • Work slowly and gently to avoid removing too much material. It’s easy to over-sand quartz.
  • Keep sanders moving constantly to prevent uneven sanding spots or grooves.
  • Rinse sanding sponges frequently as they fill up with quartz dust.
  • Wear a dust mask and work in a well-ventilated area. Quartz produces fine silica dust.
  • Change sanding discs when they become clogged for optimal smoothing.
  • Expect the process to generate some white quartz dust. Protect nearby surfaces accordingly.
  • If edges feel rough or sandy after polishing, repeat the highest grits until smooth.

Maintaining a Polished Finish

With properly sanded and polished edges, your quartz countertops will maintain their smooth, glossy finish for years to come. However, here are some tips for keeping the edges looking their best:

  • Use cutting boards and hot pads to protect from scratches and burning.
  • Clean with a gentle stone cleaner instead of harsh chemicals.
  • Avoid using abrasive cleansers or scouring pads near the edges.
  • Re-polish occasionally with a 3000 grit wet sponge to restore sheen.
  • Re-seal if edges start to feel rough or porous over time.

Proper prep and sanding technique allows you to achieve seamless, polished quartz edges. With some elbow grease and attention to detail, DIYers can accomplish professional-level results. Just take it slow and gradual. Following the process from coarse grits up through finer polishing stages will transform the look of your countertops.

Frequently Asked Questions

What grit sandpaper do you use to sand quartz countertops?

Start with 50 or 60 grit to remove the most material efficiently, then work up through finer grits like 80, 120, 180 and higher until achieving the desired smoothness. Finish by polishing with a 3000 grit wet sponge.

Can I use my palm sander to sand down quartz?

Yes, a random orbital palm sander with variable speeds works well. Attach adhesive-backed sanding discs designed for stone. Keep it moving constantly to prevent uneven sanding.

How do you soften sharp edges on a quartz countertop?

Use a flexible sanding sponge in 220 grit or higher to smooth and contour sharp corners or tight seams. Apply light, even pressure while shaping the rounded profile.

Should you seal quartz countertops after sanding?

Sealing is not mandatory, but can help protect the edges if they feel porous or rough over time. Use a stone sealant product following the manufacturer’s directions.

What causes visible seams between quartz slabs?

Minor alignment or leveling issues during fabrication can create slight ledges at the seams. Sanding and polishing helps blend these seams for a continuous look.

Can I use a handheld rotary tool to sand small spots on the edge?

Yes, a Dremel-type tool with a sanding drum accessory can help spot-sand imperfections in hard-to-reach areas. Work carefully to avoid removing too much quartz.


Sanding and polishing the edges of your quartz countertops is a satisfying DIY project that can give your counters a professional, finished look. With some basic tools and grits, and attention to detail, you can achieve smooth, glossy edges. Just remember to work incrementally through the grits and avoid over-sanding. In a weekend’s time, you can transform the appearance of your kitchen or bath countertops.