[Thomas Sanladerer] wanted to create some molds using 3D printing ... Some scrap wood made a box for the positive model. [Tom] used a concrete-based mortar since he didn’t have real concrete ...

2. Using a scoop, place concrete in the cylinder molds. For 6 by 12 inch molds, place in three equal layers (1/3 volume per layer) and for 4 by 8 inch molds, place in two equal layers (1/2 volume ...