KP-55 Wave Washer 520K16

The 520K16 wave washer is a precise metal spring washer made to fit the nail-drill handpieces in the KUPA KP series (KP-55, KP-55A, KP-60, and KP-60A, for example).  With its wavy or corrugated design, it may impart a constant preload or stress between components, allowing it to take up minor clearances under high-speed rotation and ensure good bearing/spindle alignment.  Part number in KUPA's parts catalog for high-speed parts. Features OEM‐design: Specifically listed by KUPA for the KP-series, indicating correct fit and function.  Dimensions (typical): Inside diameter ~ 6.04 mm; Outside diameter ~ 7.85 mm; Thickness range ~ 0.23 to 0.70 mm.  Material: High‐speed metal alloy, suited for the fast rotational speeds and demands of professional nail‐drill handpieces.  Function: The wave washer helps maintain preload and mitigate axial play, vibration, or misalignment in the spindle/rotor assembly. Installation Tips Verify your existing washer’s dimensions (especially ID and thickness) if it looks different or the tool is a non-standard revision. When installing, ensure the washer is oriented correctly (wave/convoluted side as intended) and seated flush in its groove or housing. Disconnect power and let the handpiece cool before disassembling. Remove the front housing/collet and any relevant rotors/spindles to access the old washer. Clean the seating surface, remove any residue or metal shavings. Place the new #520K16 wave washer carefully, ensure it sits flat and is not bent, distorted or mis-aligned. Re-assemble the tool, run unloaded at low speed to check for smooth rotation and no unusual noise or vibration before full use.