Abstract: A high speed apparatus for assembling washers on headed parts such as bolt blanks, wherein individual washers are mechanically positively placed and seated onto individual blanks. The apparatus includes a linear transfer mechanism for progressively shifting the blanks through successive stations at which a washer is first placed on the end of a blank, is then "stuffed" axially along the shank of the blank, and is then positively abutted with the head. Various movements of the washers and blanks are effected by individual servomotors that greatly simplify the complexity of the apparatus, provide timing/stroke flexibility, and independent control.