It has always been in the realm of f do-it-yourselfers to sharpen circular saw blades, but a lot of folks prefer to have professionals do the work because the cost was minimal.  With carbide tips on a lot circular saw blades, sharpening your own blades has become more difficult–but still possible. The trick to sharpening blades is to use a diamond file. Follow these steps and your saw will be sharp in no time.

Take the blade from your circular saw. This normally requires the use of an open-ended box wrench, although newer models may have other blade releases. Check your owner’s manual.

Put your blade into a vise. Close tight, but do not too tight.

Put 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 even strokes will be good enough.

Skip a blade point and repeat the same process, stroking your file four times on the beveled 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 beveled edge.

Complete filing the tips of each beveled 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.