At Onsrud,the term "fixed bridge" means cast iron. Simply put, cast iron just has a better ability to absorb and dampen cutting vibrations, while steel will tend to amplify and transmit these oscillations to the rest of the frame. When you are cutting man-made materials most of the time, a heavy, Pro Series will get the job done. But, if your primary materials are solid wood or non-ferrous metal (both of which create significantly more vibrations), then you definitely want the additional dampening ability of a cast iron frame. You'll quickly find that the cast iron frame design of the "Super Duty" Series will not only contribute to the overall weight, mass, and rigidity of the machine, but will also promote faster feed rates, better finishes, longer tool life and less maintenance.

A cast iron frame design will usually cut much deeper per pass, machines much faster, and maintains a better finish. It simply out-produces all other designs – making you more money in the process. The stationary bridge is positioned across the width of the tables – a design which only uses half of the floor space of a typical "Tubular Fixed Gantry" machine. Independently configured tables on the Onsrud Super Duty can be loaded and/or off-loaded, without interrupting the cutting cycle on the opposite table, offering you the advantage of 100% cutting time (pendulum processing).