STV CNC STVR4 PRO

The STV CNC STVR4 PRO is the welded-frame version of STV CNC's 4 ft x 4 ft router table. Travels are 48 in in X, 48 in in Y and 5.75 in in Z, the same as on the modular STVR4; the difference is that the PRO arrives fully assembled, with a 3:1 gear reduction system on its stepper motors.

What the PRO name adds is the frame and the drive. The tubular frame is fully welded and the table arrives assembled, standing on industrial leveling feet with the control box attached. Four stepper motors work through a 3:1 gear reduction system, which is an extra on the modular STVR4. A homing kit with 4 proximity sensors is built in. The rest of the motion system is shared with the modular tables: hardened and ground linear guide rails on all three axes, rack and pinion on X and Y, and a billet ball lead screw on Z with 5.75 in of maximum travel. STV CNC lists plus or minus 0.005 in per 12 in for motion accuracy, 0.0005 in for step resolution and 600 in/min as the default maximum travel speed.

A 4 ft square bed takes half of a 4 x 8 sheet, so sheet goods have to be cut down before they go on the wasteboard. That suits signs, plaques, small furniture parts and one-off pieces better than cabinet nesting. Z travel of 5.75 in is a maximum. The wasteboard and the length of the bit come out of it, so thick foam or deep carving work should be checked against what is left.

Cutting is done by a 2.2 kW (3 HP) air-cooled spindle with a speed of 24,000 rpm. It holds tools in ER20 collets, and the 1/4 in and 1/2 in sizes ship with the table. An attached variable frequency drive sets the spindle speed from a 110 V single-phase input. The dust shoe releases magnetically for bit changes and has a 2.5 in port for the shop's own collector. Optimum CNC, the maker's control software, comes installed on a mini PC that connects by Ethernet. Plan separately for a monitor, keyboard and mouse, for the wasteboard and its fasteners, and for the dust extractor hose: none of them are included.