Official Answer
Answer
Heavy-duty spiral rings have a thicker cross-section and higher spring rates, making them difficult to expand over a shaft. To prevent scratching or gouging the shaft, a 'bullet' or 'pilot' tool should be used. This tool is a hardened cap that fits over the end of the shaft, providing a smooth, ramped surface for the ring to slide up. The pilot should be lubricated with a light oil. If the ring is made of 17-7PH or another hard material, any scratch on the shaft could lead to stress concentrations and fatigue failure of the shaft itself. Additionally, the ring should be wound onto the shaft in a way that the 'trailing' end doesn't snap down and mar the finish.
