STV CNC Optimum 12

At 12 ft x 6 ft, the STV CNC Optimum 12 has the largest standard cutting envelope in its series. It is the servo-driven table at the top of the STV CNC range, with an enclosed welded frame and its own control computer. A table this long is chosen for the part, not the sheet count: 12 ft covers long plates and frame members in one program with no re-indexing.

The mechanical parts are a step up from the stepper tables in every row of the maker's comparison. Three servo motors drive through 5:1 planetary gear reduction onto helical rack and pinion, the linear guides are hardened heavy-duty units, and the gantry is machined metal instead of extruded aluminum. Stated motion accuracy is about 0.001 in per 12 in, with a step resolution of plus or minus 0.00008 in. Gantry clearance is 6.75 in and Z travel 5.5 in. The enclosed tubular frame is welded, the single welded water pan is 4 in deep, and plate capacity is 2 in of steel. Motors sit in housings and full-length shields cover the guides against splash.

Everything scales with it. The water pan holds about 167 gallons. STV CNC lists the occupied area as about 14 ft x 9 ft x 5 ft. The table weighs 2,300 lb, which sets what the truck and the forklift have to be. Material at this size arrives by crane or forklift, and the shop needs a clear run to the table as long as the sheet itself.

The control is Optimum CNC, running on a Linux mini PC that comes with the table and talks to it over Ethernet; the buyer adds a monitor, mouse and keyboard. Because the PC is dedicated to the table, an operating system update on an office laptop cannot stop production. The software reads .dxf and G-code files and has 80+ editable shape templates. Four proximity sensors handle homing and gantry alignment. Torch height control, a magnetic breakaway with a cable catch and a collision switch are standard, and the plasma cutter is sold separately.