A shaped charge carrier tool is provided that has particular utility for perforating well casing as a preparation for cement placement. A plurality, four or more elongated shaped charge carrier ribs having a high bending modulus are secured for radially expanded displacement around a central framing tube or rod. Radius rods link the ends of the carrier ribs to top and bottom hinge carriers. The hinge carriers encircle the framing tube and are free for axial translation along the framing tube. Articulating hinges connect the radius rods to the carrier ribs and to the hinge carriers. Opposed compressed coil springs provide a resilient bias on the hinge carriers to translate the carrier ribs radially outward against the interior surface of a well casing as the tool passes from a riser tube into a larger inside diameter well casing.