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Unless you damage the edge, or get into restoring eBay specials, a 12-15k hone is all you'd need for at least a year, perhaps longer. My Norton combo has sat, untouched, since 2012.

In the event...

Before you rush out and get a Norton combo stone, take the time to read about The Famous/Infamous Norton 4/8 "JaNorton 2012"
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