Originally Posted by
tomato coupe
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The two charts you referenced in a previous post list 5.00 mm and
#10 (4.91 mm) as the drill size for M6 x 1 threads.
Hmmm. Don't know how I morked that up. But the 4.91mm corresponds to my 4.89mm for 100%. Having some talent for breaking taps, I think I'm going with the larger holes!