Reply by 000

get a better class of blade. Tenru, Ridge Carbide, Ghudo get a better class of blade.

It is hard to imagine it is not the blade/s
you took it step by step bringing the system on motor first then the belt and arbor and then finally the blade and you got no vibration until you add the last element – the blade – and that’s the only time it vibrates
What else is there but the blade?

You might try cleaning it

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