The most important stages of setting, is in the "clean-up". Some setters just finish the filing & run to their polishing machine, not I Those setters spend so much time making every claw/prong true in it's edges or corners. But once the rotating 'cloth wheel' touches the ring, all of those sharp corners get literally 'rounded or obliterated'. The 'clean-up process', is equivalent to at least 33% of the setting time!
What tools will a 'high calibre Diamond Setter' use in the finishing stages of a clean-up? Let's just say that after the "Emery-Disk" shaping will remove much of the marks on the claws, I use my favourite cleaning wheel & that is a Pumice Wheel with a "Flat Face" or 'Tapered Wheel" of #180 grit! Anything courser, is damaging to the ring. After these finishing wheels are used, I will use (if needed) a Pumice Wheel (Pink) of #1,000 grit. These particular wheels can really put a decent finish on the metal. What you are doing is getting into the 'hard to get to' places no cloth, polishing wheel can get into as they will ruin the 90-degree corners.
This process is very exacting, as I need to examine each contact spot during this process. I will interchange one Flat-face with a Tapered Pumice wheel constantly & back and forth till the ring is up to my high finishing standards. This is really the last setting stage prior to giving the ring to the client. All file marks must be eliminated while the ring will be in your hands. There is tremendous stress upon you, the setter! All of your Pumice wheels must be clean not worn down. You want a flat or tapered face on the Pumice wheels, then use pumice wheels that are correctly suited for that cleaning process!!!
I usually use a Carborundum wheel to refurbish & clean the front or side of the Pumice wheels. If I have the opportunity, I will examine the inside of the shank. I want the whole ring to be free of any form of defects, only the pumice wheel will assist me.
This cleaning process is a definite '7+ out of 10'! Why so difficult, your jewellery item must be totally clean. This is an 'exacting skill', don't be intimidated by it's complexity.