Re: Refurbishing an old 30 frame Extractor.
Note that even brand new extractors have an exposed bearing inside the drum. This is OK because a food-grade grease is used on the bearing. The bearing that I am familiar with is essentially a single large stainless steel ball sitting inside a cup-like housing. Modifying an existing extractor to use a sealed bearing is not a route that will be very fruitful, IMO.
I agree with Ollie's comments above, but if you do decide to paint, CamCoat paint is one to consider:
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