The PE Step Roller Tool from RPToolz is 195 mm long and constructed of Eloxed Aluminum (dyed blue) for use in rolling Photoetch (PE) brass, copper, aluminum and other malleable metal sheet, wire, and some shapes. The Eloxed (electrochemically oxidized) process creates a hardened anodized surface to resist scratches and wear.

The steps in the roller tool correspond to diameters of 4, 6, 8, 10, 12, 15 and 20 mm.

I found the tool capable of repeatedly making consistent-sized rings in wire and barrels in sheet.

By wrapping the material to be rolled around the tool, the material will form a curvature based on the diameter of the rolling tool plus any spring back. The stiffer, and less malleable (or ductile) the material rolled, the greater the spring back once released from the force used to roll the part. In order to create the curvature desired, it may need to be rolled around a smaller diameter to account for the spring back (which has the effect of producing less curvature and greater diameters than the roller diameter used to form it). Beware of work hardening where excessive or repeated deformation reduces malleability and may crack the material. Some materials may need some heat treatment beforehand in order to be malleable enough to bend or re-bend successfully.

Soft foam makes a useful substrate to form the initial curve by placing the part or shape between a soft foam block and roller tool, forcing the Step Roller Tool as far into the foam as possible, then I repeat using a smaller diameter step. I repeat these steps with progressively smaller steps until the desired curvature is produced. I find it useful to have a variety of soft foam blocks of various thickness and various softness in order to choose the right combination for various materials, shapes, thicknesses and curvatures anticipated.

In order to create rings or spiral shapes, I prefer to clamp one end of the part to the roller tool in such a way that I can wrap the loose end around the roller with my fingers (however, pliers may be useful to coax larger shapes around the roller tool).

I can recommend this durable step roller tool for modelers needing to impart precise curvature onto photo-etch (PE) and other malleable shapes. The reviewer thanks UMM-USA for providing this tool for review by the IPMS Reviewer Corps.