Circular saw kickback: why it happens and how to stop it

What kickback is

A circular saw blade spins upwards at the front and back towards you at the rear. If the wood closes on the blade, or the saw twists so the rear teeth catch, those teeth climb out of the cut and the saw is pushed back and up. Riving knives and blade guards help, but the cause is usually how the work is supported.

Kickback is more likely with long rip cuts, wet or twisted timber and when the blade is set too deep.

The common causes

Most kickback comes from a handful of situations, and each one has a simple fix once you know to look for it.

How to set up a safe cut

Good setup prevents most problems before the saw starts, and it takes only a minute or two for each cut.

1. 1

   Support the board on a bench or sawhorses with battens so both sides of the cut are supported.

2. 2

   Set blade depth so the teeth just clear the underside, usually a few millimetres.

3. 3

   Clamp a guide or use a rail for straight cuts; see our guide to cutting straight.

4. 4

   Check the guard moves freely and the riving knife, if fitted, is aligned.

5. 5

   Stand to one side of the blade line, never directly behind the saw.

6. 6

   Let the blade reach full speed before it touches the wood.

See track saws with anti kickback →

During the cut

Hold the saw with both hands and keep it moving at a steady pace. If the saw slows, the motor labours or you smell burning, stop, let the blade stop and check for pinching. On long rips, tap a small wedge into the kerf behind the saw to keep it open. Never back the saw out of a cut while the blade is spinning.

Read how to cut straight with a circular saw and circular saw binding and burning for related fixes.

Note:Keep hands well clear of the blade line, never hold work in your hand or across your knee, and wear eye and hearing protection. Unplug or remove the battery before changing blades or adjusting the saw.

Tools that reduce kickback

Many modern saws have an electric brake, and some plunge saws and higher end circular saws include electronic kickback control that cuts the motor if the saw jerks. Track saws with anti kickback rail stops add protection. A sharp blade with the right teeth for the job, as in mitre and circular saw blades explained, reduces the force needed.

If you mainly cut sheet goods, a plunge saw on a rail is easier to control; see circular saw vs track saw.

Why it often happens at the end of a cut

As you near the end, the offcut loses support. If it drops, it hinges on the uncut portion and closes the kerf on the blade. Supporting the offcut, or arranging the cut so the offcut falls freely without twisting, stops this. Ease off speed slightly at the end and keep the base flat on the board.

If you are new to the saw, practise on scrap and read how to use a circular saw.

Frequently asked questions

Why does my circular saw kick back at the end of a cut? The offcut drops and pinches the blade. Support both sides so the kerf stays open.

Does blade depth affect kickback? Yes. Setting the blade only a few millimetres below the board reduces the number of teeth that can bind.

Can a dull blade cause kickback? Yes. It needs more force, heats up and is more likely to bind. Replace or sharpen it.

Where should I stand when cutting? To one side of the blade line, never directly behind the saw.