Another method I have read about, but have no personal experience of, is to use paper between the male and female tapers. Just use a clean sheet of copy paper, Reflex or similar, and cut a truncated cone so that it fits the male taper, and after cleaning and cleaning up both tapers, just fit dry as you would a gasket. It is reported to work well to stop slipping, and I assume if there still was any slip, damage would be much less or possibly eliminated, due to the lack of any metal to metal contact.
Rob.