Symptoms
- Blade visibly wobbles when spinning
- Cuts come out wavy or angled
- Vibration is worse than normal
- Kerf is wider than the blade thickness
Likely causes
- CommonBent or warped bladeEven a slight bend shows up as wobble at speed and should not be reused.
- CommonArbor nut looseA loose nut lets the blade shift side to side.
- PossibleDebris or sawdust between blade and mounting washersAnything trapped there tilts the blade off-plane.
- Less commonWorn or damaged arbor shaftA bent shaft on the saw itself will wobble any blade you install.
- PossibleWrong washer orientation on reassemblyInstalling washers backward can seat the blade off-center.
What to do
- Unplug the saw or remove the battery before touching the blade.
- Spin the blade slowly by hand and watch the edge for visible side-to-side wobble.
- Remove the blade and check it for bends by laying it on a flat surface.
- Wipe the arbor, washers, and blade seating surface clean of sawdust and debris before reinstalling.
- Reinstall the blade with washers in the correct orientation and tighten the arbor nut firmly with the correct wrench.
- Spin it by hand again to confirm the wobble is gone before plugging in and test cutting on scrap.
Tools and parts
- Circular saw
- Wrench for arbor nut
- Clean rag
Replacement circular saw bladeSearch: “circular saw blade replacement”
When to call a pro
If a fresh blade still wobbles after a clean reinstall, the arbor shaft itself may be bent and the saw likely needs professional repair or replacement.
Safety
Use caution
Keep the saw unplugged or the battery removed any time your hands are near the blade.