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What Is The Difference Between The Different Grits Of Sandpaper?

Have a big project ahead of you? Or maybe just a little one?

Whatever size project you have coming up, you stumbled across this article because you’re going to need some sandpaper.

Well, you came to the right place.

Don’t just go out and acquire any sandpaper! Depending on what your project is, you need to make sure you choose the proper grit of sandpaper.

Believe it or not, each grit accomplishes something completely different and you could end up ruining your floor or furniture if you use the wrong one.

Okay, so let’s get into it and answer the question: what is the difference between the different grits of sandpaper?

What is Grit?

Before we answer that question, it may be helpful to know what grit is even referring to!

Well, the different grades simply represent the difference in the quality of the abrasives.

They are numbered from 0 to 400. What the number represents is the number of sharp particles per square inch on the sandpaper.

So, just to be really granular, a sandpaper with a grit of 50 would mean 50 sharp particles per square inch, and the rougher than sandpaper will be.

If it had a grit of 300, there would be many more particles per square inch which would make it much smoother.

Open-Coated vs. Close-Coated

This is another adjective used to describe the grit of the sandpaper. It is referring to whether or not there are gaps between the grits.

Open-coated sandpaper, as the name suggests, has gaps between the grits!

What is the purpose of this, you may ask?

Well since there is space between the grits, it allows for sawdust or any other particle waste to get trapped in there. This is accommodating because it keeps them out of the way and doesn’t allow it to interfere with the rest of your sanding.

It’s good to use open-coated sandpaper with a power sander as it goes much faster and is creating much more waste.

Close-coated of course means that those gaps don’t exist. This is better for smoothing out wood (or anything else) as the sandpaper is basically finer.

When to Use What Grit

If you need to strip something completely, get rid of some heavy blemishes, or do some severe sanding – you’re going to want a lower grit (say, 40 to 60).

This is extremely coarse and is going to remove anything. Make sure you don’t use this unless you absolutely need to.

If you use a lower grit sandpaper on a piece of wood that’s already smooth, it’s simply going to scratch it up.

Now that we know what a lower grit is used for, the opposite is going to be true for a higher grit.

These will look smoother and also feel a little smoother when you touch it.

If something has some smaller shortcomings or you just want to do some general smoothing out, use something in the range of a medium grit (AKA 80 to 120).

Lastly, if you have a piece of furniture that’s already pretty smooth and you just want to get rid of a few small blemishes, go for a really high grit (360 to 600).

Often time when you’re working on a project, you’ll work your way through all the grits of the sandpaper.

Finishing something that’s been sitting in your garage for a while? You might want to start off using a low grit sandpaper on a power sander to do the initial smoothing out.

Once you’ve done all you can do at that level of grit, move up the medium, and so on.

You’ll be able to tell when it’s time to move on when the sandpaper you’re using is no longer making the surface any smoother.

Sandpaper Materials

In addition to the grit of your sandpaper, you’ll also want to pay close attention to the type of material. If you use the wrong type of material, you could end up ruining your surface.

On a more minor scale, you could just end up doing more work than you need to or not being as efficient as you would like to be.

So, what are the most commons versions of sandpaper?

Aluminum Oxide

This is a synthetic abrasive and is perfect for all types of hardwood.

It’s a super durable synthetic and is not only strong enough for hardwood but is also great for sanding and polishing a variety of steels.

Garnet

Most abrasives are synthetic, but this is a good natural alternative. It’s best used for the fine sanding of wood.

Unfortunately, this is going to dull relatively quickly so it’s not going to be great for metals or super hardwoods.

Silicon Carbide

This is going to be the most versatile of the abrasives. This is because it happens to be the most durable of all synthetic abrasives.

It works great on just about all metals but also plastics, hardwoods, and softwoods.

Ceramic

Ceramic is the most expensive and roughest grit. Its primary purpose is to shape different types of wood.

Emery

If you want something that’s powerful but natural as well, then consider Emery. It’s a natural material but is powerful enough to remove corrosion on metals but also polishes steel and other metals.

Be careful, though! This is natural, but it is going to be too sharp for sanding wood.

Conclusion

You may be overwhelmed at first by all the diverse materials and grits, but it’s honestly quite manageable once you break it down.

Learning about sandpaper and when to use it is a great first step in a lot of DIY projects.

Sandpaper can help you transform the oldest, most beat-up furniture into wonderful works of art that will look amazing in your home.

The main piece of advice we can give you is to make sure you don’t use extremely coarse sandpaper on furniture that’s nicer or already smooth.

Other than that, we’re confident you can tackle any sanding project now.

You’ve read the different grits of sandpaper. Take time to read our other guides about the best wheelbarrow and the best electric smoker. You might buy one from the list after you read.

Jimmy is the lead writer here on Garden Reviewster. He works part-time at his local Lowe's store while writing and editing on the side. With his 8+ years of experience working with garden equipment, his skill set is an excellent match for the site.