How to choose the right sandpaper grit?

No matter the job, whether you are sanding the rust off a car panel or starting a new woodworking project you need to make sure you are using the correct sandpaper grit for the job. Choosing the wrong grit will, at best, take you much longer to finish the job, and at worst, cause irreversible damage to your project.

So it’s important before starting a job to understand which sandpaper grits to use.

First, how is grit determined? Sandpaper grit is determined by identifying how many abrasive particles can fit in a 1” square at a time. If you are a visual learner, try drawing a 1”x1” square on a piece of paper and then drawing equal sized circles within the square to see how many fit. For example, in the case where the sandpaper is labeled as 24 grit, 24 circles would fit within the 1” square. There are a number of established standards from UAMA (U.S.) and FEPA (Europe) that provide the average grit size and allowances for variation.

Now this is good to know, but it doesn’t really help you pick the right grit for your job, does it? Below you will see an outline of which grits you should be using. Although, you may need to make adjustments depending on the material you are sanding.

In general:

  • Lower grit numbers or coarser grits are generally used for aggressive sanding of tough materials and for removing/shaping wood.
  • Higher grit numbers or finer grits are generally used for surface preparation and finish sanding.

Using the grits in series is also very important, a lot of people are tempted to jump grits for example going 60 grit to 120 grit while sanding but this is a mistake. By jumping to many grits you will spend extra time removing scratch marks from the previous grit.

Very Coarse – Deep fast cut for fast material removal. This is commonly used for removing varnishes on hardwood floors. 12 – 36 Grit
Coarse – Used for aggressive cutting and shaping of wood. 40 – 50 Grit
Medium – Sanding of rough wood, removal of cut marks or deep scratches. 60 -80 Grit
Fine – Finish sanding. 100 – 120 Grit
Very Fine – Finish sanding. 150 – 360 Grit
Ultra Fine – Final sanding finish, polishing. 400+ Grit

We hope this helps. If you have further questions, please message below or reach out to us directly. We can help you find the abrasives you need.

And if you’re looking for sandpaper or other abrasive products, please check out our Shop.

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