as oil, I used WD-40
and elbow grease 
 
for cleaning, remove rust or spots 
1) emery cloth
2) to smooth the emery marks, steel wool
3) application of metal polish "Briliant" as deep cleaner
4) application of wax polish "Renaissance" to allow manipulation without gloves, and prevent oxydation
I spread inside scabbards  WD-40, that feed the wood, or prevent any metal oxydation
à +
Dom