Onsrud Bridge Series

The Onsrud Bridge Series is a heavy-duty moving-table gantry CNC router built for precision machining applications where maximum structural rigidity and thermal stability are required. Unlike moving-gantry configurations where the bridge travels over a fixed table, the Bridge Series moves the table beneath a stationary bridge — an architecture that concentrates the machine's mass in a fixed overhead structure and allows the table to carry the workpiece through the cutting zone. This configuration delivers exceptional rigidity for heavy workpieces, dense composite laminates, and applications where tool path accuracy must be maintained under high lateral cutting loads.

The Bridge Series is designed for industrial composite trimming, aluminum routing, foam tooling block machining, and large mold pattern production where the workpiece mass would create dynamic problems in a moving-gantry machine. The stationary bridge eliminates the inertia management challenges of moving a heavy gantry structure at production feed rates — a critical advantage when machining programs require rapid direction changes or high-accuracy contouring on large workpiece surfaces. Linear guide rails on the table and bridge axes provide smooth, low-friction motion with high stiffness across the full travel range.

Spindle configurations on the Bridge Series are matched to the heavy-duty cutting applications it targets. High-power electrospindles with liquid cooling support sustained full-load operation in dense composite stacks and aluminum blocks without thermal drift affecting dimensional accuracy. Automatic tool changers with high tool-count magazines are standard, enabling complex full-cycle machining programs to run without operator intervention. Optional 4-axis and 5-axis heads are available for contoured machining operations on curved mold surfaces and angled composite features.

The Bridge Series work envelope is determined by table dimensions and bridge span, with configurations available from approximately 5-foot by 8-foot tables up to custom large-format installations. The moving-table architecture means that the machine's footprint is larger than an equivalent moving-gantry machine — the table must have full travel clearance in both directions beyond the cutting zone. Facility planning for Bridge Series installations requires careful attention to floor load ratings, as the combined weight of the machine structure, table, and workpiece can be substantial.

Onsrud supports Bridge Series buyers with the same application engineering and composite process expertise that characterizes the P-Series and XL-Series platforms. For mold makers, pattern shops, composite tooling manufacturers, and aerospace fixture fabricators who need uncompromising rigidity and accuracy in a router-class machine, the Bridge Series offers a technically differentiated solution that justifies its position at the upper end of the industrial router market.