Marking Sandpaper Sheets for Identification


When sanding small objects, I think most of us probably use the technique of cutting/tearing a sheet of sandpaper into quarters and then folding those sheets into thirds. I use Norton 3X sandpaper and, before I started using this technique, once the sheets were quartered and folded into thirds I often had difficulty identifying the grits since above 150 they’re all on the same color paper. In addition, the grit is only printed in one or two places on each full sheet, so it’s often not on the back of a quarter sheet.

The way I get around this is to color code the various grits. 150 is red, so it’s not a problem. For 220, 320 and 400 I use red, blue and green respectively to identify them. My method is pretty simple. When I remove the sheets from the box, I use a sharpie of the appropriate color and make two lines down the length of the paper and in what will be about the middle of the quarter sheets. It’s not important that the lines are neat, but it is important that they run from edge to edge. That way when the quarter sheets are folded into thirds the line appears on each third.

It doesn’t take much pressure to make the lines so don’t press to hard. Use light pressure and the sharpie will last a long time. Press too hard and it’s quickly ruined.

The lines remain vivid throughout the life of the paper and I’ve never had the colors transfer to a piece I’m sanding. No more hunting for the grit on the back of the paper. No more rubbing the paper and trying to decide if it’s old 320 or relatively new 400.