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robert sorby
https://www.rockler.com/robert-sorby-827c-external-shear-scraper-replacement-blade
This (rounded) square cutter is used for scraping outside curves on bowls, vases and spindle turnings.
robert sorbyexternalshearscraperreplacement
https://www.rockler.com/robert-sorby-extra-heavy-duty-scraper
Robert Sorby Extra Heavy Duty Scraper: Excellent for large bowl work, platters and deep hollowing.
robert sorbyextra heavydutyscraper