Bridge Mill Tackles High Speed Net-Shape Machining

The Hi-Net DMC-900HN by Johnford is suited for aerospace manufacturers and mold/die shops that need speed, rigidity and precision in a competitively priced double-column machining center. Absolute Machine Tools, Inc. offers this 26,400-lb bridge mill, which is designed for high speed, net-shape machining of complex 3D parts.

The machine is capable of accurately cutting a variety of materials at high feed rates, the company says. Heavy Meehanite castings provide the strength and vibration damping required for quality surface finishes and long cutting tool life. The columns and bridge are a one-piece casting. The Z-axis head and Y-axis saddle feature square box ways and diagonally arranged ribs to minimize distortion.

The machine features a moving-table/fixed-column design for rigidity. A 90-degree bridge with offset Y-axis ways and a wide saddle keep the spindle centerline close to the bridge for further rigidity, the company says. X-axis table traverse is accomplished via Schneeberger roller linear ways for accurate positioning of heavy workpieces. The machine also includes large-diameter, pretensioned ballscrews and powerful servomotors for accurate positioning. The bridge mill delivers X-, Y- and Z-axis travels of 35" × 35" × 30" and rapid rates of 944" × 944" × 590".