Design and construction of a machine that cuts 80-microns slices of sound and carious dental enamel and other calcified tissues is described. These slices can be used for quantitative microradiographic studies. Preparation takes minutes. Thickness for a given slice is uniform within 2 microns, mean thickness is within 4 microns of the intended value and roughness is about 0.1 micron. Commercial components have been used where possible. Information is provided to permit purchase of the components of the machine and its construction in the average university workshop.