Spindle pull back force checking gauge are an essential part of preventitive maintenance on machine spindles with pull back grippers.
By testing and checking regularly, failing grippers can be detected early, allowing for plannned maintenance rather than the panic of a spindle failure. Spindles use springs and washes to create the tool holder grip force. After time the constant grip and release will weaken them reducing the amout of force applied. The consiquence of this can be vibration in the machining process resulting in poor surface finish, reduced tool life, and damage to spindle bearings.