C’ bore Coarse bore---This has a tolerance class of 7H for internal threads and 8g for external threads " w" e4 A% B7 H4 h. USHCS Screw hole countersunk head) j* z) v C# c9 H; Z; R1 B
¼ Major Dia. Of threads . inch# Q4 `6 V: T: G7 f X7 r: X, e
" R X# ?3 A- L3 I7 i. q* l+ F: D
#1, drill hole Dia. 5.7192mm
第一个貌似讲述的是,钻1/4内六角螺钉(Socket Head Cap Screw)使用的沉头孔(Counter Bore),钻到图示的深度% z6 [4 K. Q. T! n
第二个貌似讲的是一个不太紧的紧配合(Loose Press Fitting)孔的尺寸参考第一张零件图。& U0 `5 h+ x# O. a# n5 B
(仅供参考)