Abstract: During injection molding of a plastic product having a base wall and a sidewall, alignment of the mold parts that shape the mold cavity is maintained by conducting injected plastic material through a sequence of variable-opening throttles in a base-wall-section flow guide of the mold cavity. The openings of the throttles vary in response to variations in the thickness of a region of the sidewall section into which injected plastic material is conducted from the base-wall-section flow guide so that upon an increase in the thickness of such region the openings of the throttles in the base-wall-section flow guide decrease and so that upon a decrease in the thickness of such region the openings of the throttles in the base-wall-section flow guide increase.

Abstract: An interlockable element for a structure assembly set includes an at least partially planar body and a connector edge having associated therewith a first A-type and B-type connector pair disposed about a first axis of rotation and a second A-type and B-type connector pair disposed about a second axis of rotation. The first and second axes of rotation are disposed on opposing sides of a generally rectangular quadrilateral of a specified dimension. Each of one pair of diagonally opposite vertices of the quadrilateral are situated internally to each of the A-type connectors and each of the other pair of diagonally opposite vertices of the quadrilateral are situated internally to each of the B-type connectors; and the quadrilateral is generally disposed in a plane that is generally perpendicular to the plane of the body of the interlockable element. The A-type connectors are interlockable with the B-type connectors.