Abstract: A turret roll forming machine includes at least one turret assembly carrying multiple rows of tooling (e.g., forming rollers), rotatable about an axis to selectively align rows of tooling with an input or output. A transmission is accessible from an exterior of the turret assembly without disassembling of the turret assembly to perform a changeover of roll tooling and/or maintenance on gears, bearings, or shafts of the transmission. Thus, a chain drive may be employed, advantageously accommodating differing rotational speeds for top and bottom forming rollers of each pair of forming rollers, e.g. to reduce roll scuffing. Pairs of forming rollers may be provided as cassettes, which are removably coupleable to the turret assembly allowing quick and easy reconfiguration and/or servicing, minimizing negative effects of changeover. The turret assembly may be a unitary structure (e.g., a weldment) improving rigidity and increasing accuracy of roll forming operations.