Tornos Sigma 20

TISIS (Tornos Interactive Software Integrated System) is Tornos's Windows-based programming environment for the Sigma CNC multi-spindle series. TISIS provides: graphical cycle programming with drag-and-drop tool motion definition; complete 3D simulation of all 6 stations simultaneously; automatic collision detection between tools, workpieces, and machine components; cycle time analysis and station balancing tools; and post-processing to the machine CNC. On traditional cam-driven multi-spindles, programmers physically set cam profiles and run trial parts to detect collisions — this takes 4–8 hours per new part. TISIS compresses this to 1–2 hours of software programming with virtual verification before any metal is cut, reducing scrap and setup risk.

For a typical M2.5 bone screw in titanium grade 5 (6Al-4V): the Sigma 20 achieves cycle times of 8–15 seconds per part at production parameters, producing 240–450 parts/hour. On simpler brass screws (M2 watch movement): cycle times of 3–6 seconds are achievable, producing 600–1,200 parts/hour. A comparable Swiss-type single-spindle lathe produces the same medical screw in 25–40 seconds, yielding 90–144 parts/hour. The Sigma 20's productivity advantage is 3–5x for these applications, directly reducing cost per piece and labor cost per hour of machine operation.

Swiss-type lathes (Citizen Cincom, Tsugami, Star) are single-spindle machines with excellent surface finish capability and flexible setup — ideal for high-mix, small-volume production of 1,000–50,000 parts. The Sigma 20 multi-spindle is optimized for one or a few part families at very high volume — 500,000–5,000,000 parts/year. In watchmaking, Swiss-type lathes handle prototype and small-series production; Sigma multi-spindles handle mass production of standard movement components like balance wheel screws, pillar plate posts, and jewel settings. The Sigma 20's cycle time per part is 3–5x lower than Swiss-type, but its changeover time (1–3 hours vs 30–60 minutes on Swiss-type) makes it economical only on long production runs.

For traditional Swiss watchmaking: CuBe2 (copper-beryllium, excellent machinability for complex shapes), CuZn37 and CuZn39Pb2 (free-cutting brass for gear blanks and plates), 20AP and 11SMnPb30 free-cutting steel (for pinions and stems). For modern watch components: 316L stainless steel, titanium grade 2 and grade 5. The Sigma 20's independent spindle speed allows optimizing cutting parameters per material — brass runs at 6,000–8,000 RPM; titanium requires lower speeds (2,000–4,000 RPM) and higher coolant pressure. Chip control is critical in multi-spindle work — free-cutting materials (with sulfur, lead, or lead-free additives) break chips cleanly, preventing jam in the multi-station environment.

Yes. Tornos offers an optional back-working unit for the Sigma 20 that grips the part after parting-off and performs additional operations on the back face (center drilling, reaming, threading, facing) before the part exits the machine. Back-working enables truly complete parts — both faces fully machined in one cycle — eliminating the secondary operation on the back face that would otherwise require a second machine or manual operation. The back-working spindle is independently controlled and can run simultaneously with the main drum stations. For watch components requiring precision bore and face machining on both ends (such as case components and movement plates), the back-working option enables single-cycle completion.