Eyup peeps. Does anyone have any experience with one of these ? Just wondering if its worth a punt. Has some kind of graver that lowers to grind off the staff rivet.  https://www.ebay.co.uk/itm/204090114806?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=5h9wflT9SKS&sssrc=2349624&ssuid=tBiLZaCfRb2&var=&widget_ver=artemis&media=COPY