According to an example, a three-dimensional (3D) printer may include a spreader to spread build material granules into a layer on a build area platform, a pressing die positioned above the layer of spread build material granules, in which the pressing die is to apply pressure onto the layer of build material granules to fragment the build material granules into primary particles to increase the density of the layer of build material granules, and a printhead to selectively deposit a fusing agent between the primary particles of the spread layer of build material granules.