Cause: Saw arbor badly worn due to improperly seated blades.
Remedy: Be certain the blade is proerly seated on arbor before tightening flange.
Cause: Blade flanges not properly tightened permitting blade to rotate on shaft.
Remedy: Always wrench tighten the arbor nut. Never hand tighten. Always use hex nuts. Never use wing nuts.
Cause: Blade flanges or arbor shaft worn and not providing proper blade support.
Remedy: Check blade flanges or arbor shaft for wear. Both flanges should be no less than that recommended by the manufacturer. Replace worn parts.