While it was always possible for do-it-yourselfers to sharpen circular saw blades, many people simply chose to have professionals do the work because the expense was so small. Today, with carbide tips on most circular saw blades, sharpening your own blades has become somewhat more challenging--but still doable. The trick to sharpening blades is to use a diamond file. Follow these steps and your saw will be sharp in no time.
- Skill level:
- Moderately Easy
Things you need
- Circular saw blade
- Flat or three-sided diamond file
- Open-ended box wrench
Remove the blade from your circular saw. This generally requires the use of an open-ended box wrench, although newer models may have other blade releases. Check your owner's manual.
Place your blade into a vice. Close snugly, but do not over-tighten.
Place a chalk mark at the top most blade point so you will know when you have gone all the way around the blade. Notice that every other blade point has a bevel on the side facing you. Hold your file (a diamond-file if you are sharpening a blade with carbide tips) at a 20-degree angle and stroke it lightly along the bevel of the first tip--stroke up, down, up and down. Four nice even strokes should be enough.
Skip a blade point and repeat the same process, stroking your file four times on the bevelled edge, sharpening the point.
Turn the blade over when you have gone all the way around the blade, sharpening every other point. You will know when you are done because you will come back to your chalk mark. On the other side of the blade, put another chalk mark and do the same thing as you did to the first side, starting with the top most point with a bevelled edge.
Complete filing the tips of each bevelled tooth. Now place the file between the two top most teeth, with the flat side of the file against the leading edge of one of the points. Run your file back and forth just one time across the front edge of the tip of the blade point. Do this to all of the tips, and your blade will be sharpened.
Tips and warnings
- Do not try to take off too much material during the sharpening. Four strokes on each bevel and two strokes on the leading edge of the point should be sufficient to sharpen even the dullest blades. If the blade still seems dull, repeat the entire procedure one time, but no more.
- Always wear eye protection when sharpening blades with carbide tips.