Processing the pilot hole into a taper

"First, machine the straight pilot hole to a φ10.9 diameter. Next, use a 1/16 taper drill or tapered reamer in the straight pilot hole so that the hole diameter on the large end face does not exceed φ11.445. If your Rc it is not a through hole, there are cases where a commercially available 1/16 taper drill or taper reamer cannot be used, as the drill or reamer must exit the hole. In that case, we recommend the use of a taper end mill with a 2 ° inclination angle.
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