220-Grit Sandpaper Can't Fix an 80-Grit Mistake

You’ve sanded your project with 80-grit paper. It feels pretty good. You switch to 120, give it a quick once-over, jump to 220, and now it feels incredibly smooth. Then you apply the finish.

And suddenly, there they are: scratches. Everywhere!

Here’s one of the most important things to understand about sanding: If you can still see scratches from 80-grit sandpaper, switching to 220 grit doesn’t make them go away. It just gives you really smooth scratches.

What Is Each Sandpaper Grit Actually Doing?

A lot of beginning woodworkers think sanding works like polishing: start with something coarse and keep using finer sandpaper until the wood feels smooth. That's only part of the story.

Every time you sand wood, the abrasive leaves scratches behind. Coarse sandpaper leaves relatively deep scratches. Finer sandpaper leaves shallower ones. So when you move from 80 grit to 120 grit, the real job of the 120 isn't simply to make the board smoother. Its job is to remove the scratches left by the 80 grit and replace them with smaller 120-grit scratches. The next grit removes those scratches and replaces them with even smaller ones.

That's the progression. Skip too far ahead and the finer abrasive may take a very long time to remove the deeper scratches or may not remove them before you decide the surface "feels smooth" and move on.

Don't Sand by Feel Alone

Here's the problem: your fingers aren't particularly good at detecting sanding scratches. Your eyes are better. Before changing grits, look carefully at the surface. A bright light held at a low angle to the board, sometimes called raking light, can make scratches that were nearly invisible suddenly stand out.

Another simple trick is to lightly draw pencil lines across the surface before sanding. Sand until the pencil marks are completely gone. It isn't foolproof, but it's a great way to see whether you've actually sanded the entire surface before moving to the next grit. And don't forget the edges and corners. Your random-orbit sander can't reach everything.

Do I Have to Use Every Grit?

No. A typical progression might be: 80 → 120 → 150 → 180 → 220. But that doesn't mean every project needs to start at 80 or finish at 220. If your boards came straight out of a well-tuned planer or you've already produced a good surface with a hand plane or scraper, starting with 80 grit may actually create more work for you.

Likewise, 220 isn't automatically the correct stopping point. The species of wood and the finish you're planning to use both matter. Sanding extremely fine can sometimes make it harder for certain finishes or stains to penetrate evenly. The goal isn't to reach the highest number printed on a package of sandpaper. The goal is to create the surface your finish requires.

One More Tip: Clean Between Grits

When you finish sanding with one grit, remove the sanding dust before starting the next. Vacuum the surface or use your air compressor. Dust from the previous sanding step can contain larger abrasive particles and debris that you don't want trapped under your finer sandpaper. Then inspect the board before moving on. Taking an extra minute here can save a lot more than a minute later.

Sanding Is Where Patience Starts Paying You Back

Sanding isn't usually anybody's favorite part of woodworking. After spending hours cutting, jointing, planing, gluing and assembling a project, it's tempting to rush through sanding because the project finally looks finished. It isn't.

Finish has an irritating habit of revealing every shortcut you took while preparing the surface, so slow down. Let each grit do its job. Inspect the surface before moving to the next one.

And remember, skipping grits doesn't necessarily save time. Sometimes it just moves the time you're going to waste to a point later in the project.

At Crossroads Fine Woodworking, we help woodworkers understand not just how to use the tools, but why each step matters. From preparing rough lumber to sanding and creating a mirror-quality finish, learning the process is what turns a good woodworking project into one you're proud to show people.

And if you can still see those 80-grit scratches, put the 220 down. You're not there yet.

-Andy