Use your saw blade correctly

The axle must be perfect and without beating, otherwise, the saw blade also is going to oscillate.
The flanges should be the same, perfectly parallel, and their diameter should be at least 1/3 of the external diameter of the saw blade.
The separation rings also should be the same, rigorously parallel and with the same diameter as the flanges.
If these details are not observed, the whole thing (saw blade+axle+rings) is not going to be balanced, causing vibrations.