Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
Like I said it was costing £5 per set. If you take the top off the die you will see 4 cutters. These come out and are sharpened on a lapping wheel with diamond paste like one would do for hair trimmers, a fairly routine procedure. A machine tool sharpening company will do it, just I am miles away from any major engineering centre. When I worked for a pipeline company, they had a central stores which had a maintenance section and we handed the dies and big masonry drill bits back to them for resharpening.
BTW my local power tool company resharpens all my masonry drills larger than 7mm when they get blunt. It costs £2 per drill to resharpen and they come back like new, also my 18mm long reach masonry drill as opposed to £40 to buy a new one.
Who do you use for your drill bit sharpening?
Reply to the thread, titled "Pipe Threading Die Sharpening" which is posted in UK Plumbers Forums on Plumbers Forums.
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