What is A Bridge Mill?

A bridge mill is a vertical machining center with a fully supported, extended Y-axis (with the option for fixed angle or 5-axis heads). A bridge mill is constructed with a base/bed casting and a one-piece bridge structure that is bolted to the bed. Along the bridge structure is the Y-axis, and along the length of the bed is the X-axis.

What makes a bridge mill different from a double column machining center?

A double column machining center has the exact same design, but because it is much larger, the bridge structure is made up of three separate components—2 vertical columns and a horizontal cross beam.

How is a bridge mill different than a gantry mill?

A gantry mill is similar in construction, but the entire bridge (gantry) moves along the X-axis rather than the table moving, as with the bridge mill or double column.

How is a bridge mill different than a vertical machining center?

There are several types of vertical machining center construction—L-frame, C-frame, and bridge-style. The main difference between these machines and a bridge mill is that the Y-axis travel on a vertical machining center is limited due to the design.

What are the benefits of a bridge mill machine?

The extra travel provided by the bridge mill allows for the manufacturing of much larger, longer parts than on a vertical machining center, since machining on a vertical machining center is restricted by bed size—particularly the Y-axis. A bridge mill’s larger work envelope provides greater opportunities for manufacturers in the die/mold, aerospace, automotive, and other industries.

Bridge mill machines typically live in a space where the double column is too big and a 3-axis machine is too small – providing a middle ground, both in size and in price point.