Budd–Michelin rubber-tired rail cars which featured innovative and distinctive pneumatic tires. The company claimed that its application of tires on its rail cars afforded both a substantially more cushioned ride and increased the cars' traction by 35%. The design of Michelin's tired wheels included an aluminum safety ring and a flange that were only used in the event of a puncture or other type of tire failure; during normal operation, only the rubber tire made contact with the rail. Inspired by Michelin's success, the Budd Company set its sights on marrying the new rubber rail tires with its shot-welded, stainless-steel carbodies; it had developed
Siping (rubber) Sipe's invention was unsuccessful. It was applied to solid rubber tires, rather than pneumatic tires, and so the tires had poor wet grip anyway, owing to their limited contact patch. It was his son, Harry E. Sipe, who popularised the use of sipes in the USA for the new low-pressure balloon tires around 1939. The process was not applied to vehicle tires on a large scale until the 1950s, when superior tread compounds were developed that could stand up to the siping process. On roads covered with snow, ice, mud, and water, sipes usually increase traction. A US patent to