Abstract: A trowel blade assembly for use with a rotary surfacing machine with the assembly consisting of a relatively thick, inflexible trowel blade and a relatively thin, flexible finish blade, wherein the latter is secured with respect to the former such that when in operation on a substantially horizontal working surface, with the blade assembly selectively rotated about a horizontal axis, the finish blade is continuously in contact with the working surface regardless of the consequent variable degrees of tilting of the trowel blade with respect to the working surface.