A rigid cheeseboro clamp is a heavy‑duty, right‑angle coupler used in stage, film, and event rigging to securely join two pieces of pipe at a fixed 90‑degree angle. Made from forged or fabricated steel, it’s designed to fit industry‑standard Schedule 40 pipe (typically 1¼‑inch or 1½‑inch nominal pipe size, which corresponds to an outer diameter of around 1.9–2 inches) and provides a strong, non‑swiveling connection suitable for load‑bearing positions in lighting grids, scaffolding, or support structures. Steel cheeseboros are preferred when maximum strength is required, as they fully encircle each pipe and use a bolt‑and‑nut assembly to create high clamping force. They’re commonly used for connecting horizontal pipes to vertical standards, building pipe-based rigging structures, or attaching accessories in environments where absolute rigidity is necessary.