Please advise: how to do dynamic balancing of a fan?

1 first do static balance, rolling on the edge type guide to find the focus. Similar to grinding wheel static balance. 2, dynamic balance. Can be installed after making, can also make their own simple balancing machine. Methods: the site to do with the three-point method, more trouble. Not suitable for mass production, not introduced. Homemade balancing machine: make a bracket, padded with thick rubber underneath. (Above the bracket is a bearing seat quick release type), can be forward and reverse motor (with a simple circuit control), clutch. Install the impeller