Achieving accurate crosscuts
Crosscutting hard, wide, thick or resinous woods...or forcing your stock through the cut will often cause your blade to "climb" or produce an inaccurate cut. This is especially true with dull blades or thin kerf blades. There are two ways to minimize this problem. The first, of course, is to give your blade all he time it needs to cut without forcing it through your stock. The second is to make your cut in two passes -- the first, leaving a little less than a kerf width of extra stock on the cutoff end -- and he second bringing your cut to final dimension.
Creating a wider saw kerf
If you're building a project that calls for a saw kerf that's just slightly wider than the standard 1/8" or 9/64" created by an ordinary saw blade, try this approach. Insert a tiny piece of duct tape (or metallic aluminum or "chrome" automotive tape) in one spot between your blade and the arbor washer on one side of the blade, then tighten. This should create a very slight wobble to make a kerf that would be almost impossible to achieve with a dado set.
How to Maintain a Circular Saw
Circular saws need periodic cleaning with an unused paint brush or an air supply to remove sawdust. Better-quality circular saw blades can be professionally sharpened as needed. Less-expensive blades are more economical to replace.
How to Safely Use a Circular Saw
It is especially important to wear eye protection when operating an electric circular saw. To safely use a circular saw, select the blade appropriate to the job, firmly attach it to the saw using the arbor nut, then adjust the sole plate for proper height and bevel for the job. When ready to cut, plug the saw into an electrical outlet, firmly hold the handle, align the blade near (not touching) the mark to be cut, press the safety switch, then press the trigger switch. Slowly follow the cut mark. When nearly done, make sure the end of the wood being cut is held and will not splinter due to the unsupported weight. For safety, remember that the teeth are sharp and should not be placed on surfaces that they could damage.