The utility model discloses a variable diameter components of a whole that can function independently saw bit, it includes: mounting disc, spacing clamping ring and radial movement strip, the positiveedge ring shape array of mounting disc is provided with the several mounting groove, radial movement strip end sets up in the mounting groove respectively, be provided with several radial array's reference column in the mounting groove, the interval of adjacent reference column is equal, be provided with the locating hole that several and reference column correspond on the radial movement strip,radial movement strip front end is provided with the sawtooth respectively, one side of radial movement strip conveniently is provided with the recess, and the opposite side is provided with the gleitbretter in the recess that extends to adjacent radial movement strip, spacing clamping ring setting is in the mounting disc and press admittedly to radial movement strip end. Variable diameter components of a whole that can function independently saw bit, it is convenient to maintain, can change the terminal interval with the mounting disc center pin of radial movement strip to change the diameterthat the sawtooth belonged to the excircle, promote the adaptability of cutting work.