How big is the drill bit for the 7mm hole?
If the big point is OK, use 6.5 bit to drill a hole, and then use 7 bit reaming, we can get 7.0-7.1 hole, directly use 7 bit drilling, the hole error is the biggest. Hope to be helpful to you, please adopt.
If 7 holes are machined, 6.9 bit holes are used, and 7 reaming holes are used to obtain the qualified holes
