M6 is a much better choice as you say,A guy came in today, said he had put a cylinder head for a bike into another place to bore out some sheared exhaust studs. They had bored them out right enough, and taken them from M8 to M10. He asked if I could screw in a bolt, chop it then bore and tap M8, well that wasn't happening as it would only leave about 1/4mm wall so I suggested I make him some new studs, M10 down to 8mm for the flange and then M6 for the thread, seemingly M8 nuts would be too big so it had to be m6.
He gave me a stud with a seized on nut and it was only after I had made the new studs I removed the nut and discovered the threads are M7 Won't matter and M6 nuts are easier to get so...
Anyway just used a M10 bolt and turned it down on the CNC.
Original at the bottom.
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