Why Clean a Saw Blade?
Over time, pitch and resins build up on the cutting edges of saw blades. This effectively coats the edges, making the blade act as though it is dull.
Friction and heat increase, cutting is more difficult, and the resulting cut edges are not as clean as they could be. And while it may seem counterintuitive, dull blades are more dangerous than sharp blades. Finally, blades that cut at maximum efficiency reduce the strain on a saw's motor.
Even if you don’t use your circular saw very often, it's still a good idea to give its blade a quick cleaning two or three times a year. Take the opportunity to closely examine the tip of each tooth on the blade. If many of the teeth are damaged or getting dull, consider sharpening or buying a new one. While plain steel saw blades can be sharpened (or at least touched up) with a triangular metal file, blades with carbide-tipped teeth must be professionally sharpened, although it's usually more cost-effective to buy a new blade.
Choosing a Cleaning Solution
There are several different cleaners you can use on saw blades.
Some woodworkers favor a citrus cleaner, in large part because they can clean just about everything else around the house with the same product—a big bonus. Others use oven cleaners, but if you're like many people, you probably don't like cleaning your oven with that toxic stuff, let alone your saw blades.
Furthermore, Freud, a major blade manufacturer, claims that oven cleaners can harm carbide tips and the binder that holds them in place.
One common household cleaner that works on saw blades is Simple Green (which also cleans just about everything else around the house). Simple Green is a concentrated, all-purpose cleaner/degreaser that can be found in grocery stores and hardware stores everywhere. With a name like “Simple Green,” you might think this stuff is a wimpy health-store kind of product. Well, it is non-toxic and biodegradable, but it was originally created for industrial cleaning and degreasing.
A Quick Cleaning
Simple Green should be diluted for regular saw-blade cleaning, although it can be applied straight from the bottle for more serious gunk buildup. Follow these steps for a quick regular cleaning:
Mix one part of Simple Green with two to three parts water in a shallow container.
Remove the saw blade from your circular saw, being careful of the sharp teeth.
Place the blade into the cleaning solution and let it soak for a few minutes.
Scrub the blade's teeth and any gunky areas with a toothbrush or a small brass brush until they are clean.
Rinse the blade in water and pat it dry with paper towels before re-installing it in your saw.