The circular saw is one of those power tools that ought to be in everyone’s toolbox, but use it with due care as it can also be one of the most dangerous. Here are ten top tips to get the most out of this versatile tool.
Observe all pertinent H&S requirements with a circular saw; consider it as an inverted, hand-held table saw. Always wear suitable eye protection, a respirator or dust mask and keep hands away from the blade. If possible, connect it to a power tool extractor, though with most circular saws this isn’t possible. In case you experience kickback, never place your other hand over the saw kerf. Make sure the guard is free to operate correctly before and after using the saw.
Choose the right size machine. A saw with a blade diameter of approx. 180mm is about the right size for most applications in the workshop, home or on site.
Always let the waste piece drop away and let the blade stop before lifting the saw from the workpiece.
Choose the correct blade for the job or use a good quality, general purpose blade.
Make sure that the correct depth of cut has been set; the teeth should protrude from the underside by no more than 3mm. This helps to prevent the blade from pinching in the kerf which is one of the prime causes of kickback.
Circular saws exit the work on the ‘up’ stroke, so the face, or best side of the board should be on the underside.
To prevent pinching when sawing thin sheet material such as plywood or MDF, always support the workpiece on 2x4s placed across a pair of workshop trestles.
For long cuts which don’t need to be so accurate, use the short fence supplied with the machine. It’s also a good idea to become familiar with the idiosyncrasies of your saw which can be learned with careful practice on some waste material.
For accurate cuts across a board, use a cut-off ‘T’ square leaving the end extra long. When the saw is run along the fence for the first time, it will remove a sacrificial piece at the end. To use the jig, line up the end of the section remaining (arrowed) with the position of the cut to saw off exactly where required. Provided the internal angle on the jig is a true 90°, the board will be sawn dead square.
A similar shooting board jig (this one is 1220mm long) for sheet material can be made from some oddments of ply or MDF. The runway is made slightly wider so that the first time the saw is used on it, a sacrificial piece is removed leaving it at exactly the right width (arrowed). To use it, simply line up the edge with two points at each side of the workpiece, cramp the jig in place and saw off the waste.