During the week of March 6, a special custom-built machine was used to press apart the main driving axle on Milwaukee Road 261. The work was done to inspect the main roller bearings on the wheel, and to establish a better fit of the wheel on the axle hub. Although the wheel had not moved on the axle, it had oil bleeding from it and appeared to be wearing on the axle.
Because 261 has one-piece roller bearing housings, it required us to build our own wheel press, since most wheel presses do not have an opening that will accommodate the size of 261’s roller bearing box. The roller bearings on the 261 are the same American Locomotive Company configuration as found on Union Pacific 4-8-4 No. 844, but the design is different from those found on other steam locomotives. For example, Norfolk & Western No. 611 has a different roller bearing arrangement.
The Friends machine is capable of pressing up to 450 tons. The wheel on the 261 came off at 171.35 tons. Frank Sandberg, Jr., father of Friends of the 261 Chief Operating Officer Steve Sandberg, designed the machine. Sandberg’s Con-Tek Machine, one of the world’s largest manufacturers of industrial presses and injection molding equipment, constructed it.
The Timken Company, which manufactured 261’s roller bearing, provided all of the original manufacturing blueprints. The inspection of the 261’s main roller bearings revealed that all the bearing parts are in excellent condition. Next the steam crew will be pressing the main driver back together for turning. “It is pretty impressive to open these bearing boxes and see the massive roller bearings,” Steve Sandberg said.
