3D Accuracy Tap, C’Bore & C’Sink Standards … absolutely must have information for Tapping Holes and using Socket Head Cap Screws or Flat Head Socket Screws!

cbore 7-8 n

S.H.C.S. C’Bores:

Size:         Drill & C’Bore Dimensions:
——————————————————————-
4-40           DRILL Ø.136 THRU,
                 C’BORE Ø.218 x .14 DP.
——————————————————————-
5-40           DRILL Ø.154 THRU,           
                 C’BORE Ø.250 x .16 DP.
——————————————————————-
6-32           DRILL Ø.170 THRU,
                C’BORE Ø.281 x .17 DP.
——————————————————————-
8-32           DRILL Ø.194 THRU,
                 C’BORE Ø.312 x .20 DP.
——————————————————————-
10-32         DRILL Ø.221 THRU,
                C’BORE Ø.375 x .22 DP.
——————————————————————-
1/4-20        DRILL Ø.281 THRU,
                C’BORE Ø.437 x .28 DP.
——————————————————————-
5/16-18       DRILL Ø.344 THRU,
                 C’BORE Ø.531 x .35 DP.
——————————————————————-
3/8-16         DRILL Ø.406 THRU,
                 C’BORE Ø.625 x .41 DP.
——————————————————————-
1/2-13         DRILL Ø.531 THRU,
                 C’BORE Ø.812 x .53 DP.
——————————————————————-
5/8-11         DRILL Ø.656 THRU,
                 C’BORE Ø1.000 x .66 DP.
——————————————————————-
3/4-10         DRILL Ø.781 THRU,
                 C’BORE Ø1.187 x .81 DP.
——————————————————————-
1-8             DRILL Ø1.031 THRU,
                 C’BORE Ø1.625 x 1.06 DP.
——————————————————————-
1-1/4-7       DRILL Ø1.312 THRU,
                 C’BORE Ø2.000 x 1.31 DP.

csink 7-8

Flat Head Socket Screw C’Sinks:

Size:         Drill & C’Sink Dimensions:
——————————————————————-
4-40           DRILL Ø.136 THRU,
                   C’SINK  .10 DP.
——————————————————————-
5-40           DRILL Ø.154 THRU,           
                   C’SINK .10 DP.
——————————————————————-
6-32           DRILL Ø.170 THRU,
                  C’SINK .11 DP.
——————————————————————-
8-32           DRILL Ø.194 THRU,
                   C’SINK .13 DP.
——————————————————————-
10-32         DRILL Ø.221 THRU,
                  C’SINK .14 DP.
——————————————————————-
1/4-20        DRILL Ø.281 THRU,
                  C’SINK .18 DP.
——————————————————————-
5/16-18       DRILL Ø.344 THRU,
                   C’SINK .21 DP.
——————————————————————-
3/8-16         DRILL Ø.406 THRU,
                   C’SINK .25 DP.
——————————————————————-
1/2-13         DRILL Ø.531 THRU,
                   C’SINK .27 DP.
——————————————————————-
5/8-11         DRILL Ø.656 THRU,
                   C’SINK .34 DP.
——————————————————————-
3/4-10         DRILL Ø.781 THRU,
                   C’SINK .42 DP.
——————————————————————-
1-8             DRILL Ø1.031 THRU,
                   C’SINK .56 DP.
——————————————————————-
1-1/4-7       DRILL Ø1.312 THRU,
                   C’SINK .71 DP.

tap 7-8-9 n

Tapped Holes:

(Normal engagement, drill depth to point of drill)   (Short engagement, bottom tap)
Size:        Drill & Tap Dimensions:             Drill & Tap Dimensions:
——————————————————————————————————————————–
4-40         DRILL Ø.089 x .50 DP.,             DRILL Ø.089 x .24 DP.,
              TAP 4-40 x .38 DP.                    BOTTOM TAP 4-40 x .19 DP.
——————————————————————————————————————————–
5-40         DRILL Ø.101 x .53 DP.,             DRILL Ø.101 x .26 DP.,
              TAP 5-40 x .41 DP.                    BOTTOM TAP 5-40 x .19 DP.
——————————————————————————————————————————–
6-32         DRILL Ø.106 x .56 DP.,             DRILL Ø.106 x .29 DP.,
              TAP 6-32 x .44 DP.                    BOTTOM TAP 6-32 x .22 DP.
——————————————————————————————————————————–
8-32         DRILL Ø.136 x .59 DP.,             DRILL Ø.136 x .33 DP.,
              TAP 8-32 x .47 DP.                    BOTTOM TAP 8-32 x .25 DP.
——————————————————————————————————————————–
10-32       DRILL Ø.161 x .62 DP.,             DRILL Ø.161 x .38 DP.,
              TAP 10-32 x .49 DP.                  BOTTOM TAP 10-32 x .29 DP.
——————————————————————————————————————————–
1/4-20      DRILL Ø.201 x .72 DP.,             DRILL Ø.201 x .48 DP.,
              TAP 1/4-20 x .56 DP.                 BOTTOM TAP 1/4-20 x .38 DP.
——————————————————————————————————————————–
5/16-18    DRILL Ø.257 x .82 DP.,             DRILL Ø.257 x .59 DP.,
              TAP 5/16-18 x .65 DP.               BOTTOM TAP 5/16-18 x .47 DP.
——————————————————————————————————————————–
3/8-16      DRILL Ø.312 x .95 DP.,             DRILL Ø.312 x .70 DP.,
              TAP 3/8-16 x .75 DP.                 BOTTOM TAP 3/8-16 x .56 DP.
——————————————————————————————————————————–
1/2-13      DRILL Ø.422 x 1.25 DP.,           DRILL Ø.422 x .93 DP.,
              TAP 1/2-13 x 1.00 DP.               BOTTOM TAP 1/2-13 x .75 DP.
——————————————————————————————————————————–
5/8-11      DRILL Ø.531 x 1.37 DP.,           DRILL Ø.531 x 1.09 DP.,
              TAP 5/8-11 x 1.12 DP.               BOTTOM TAP 5/8-11 x .88 DP.
——————————————————————————————————————————–
3/4-10      DRILL Ø.656 x 1.75 DP.,           DRILL Ø.656 x 1.36 DP.,
              TAP 3/4-10 x 1.50 DP.               BOTTOM TAP 3/4-10 x 1.12 DP.
——————————————————————————————————————————–
1-8           DRILL Ø.875 x 2.24 DP.,           DRILL Ø.875 x 1.81 DP.,
               TAP 1-8 x 1.88 DP.                   BOTTOM TAP 1-8 x 1.50 DP.
——————————————————————————————————————————–
1-1/4-7     DRILL Ø1.109 x 2.68 DP.,         DRILL Ø1.109 x 2.27 DP.,
              TAP 1-1/4-7 x 2.25 DP.              BOTTOM TAP 1-1/4-7 x 1.88 DP.

tap 5-16-24 n

Get a PDF copy of 3D Accuracy’s Tap, C’Bore & C’Sink Standards. Includes images and detailed information such as:

~  UNC (course thread)
~  UNF (fine thread)
~  Includes the fraction, number or letter drill size
~  C’Bores sizes to use on hard materials
~  C’Bores sizes to use on soft materials
~  Standard & Low Head Cap Screw sizes
~  C’Sink dimensions for under screw heads
~  Tolerances
~  C’Sink Sizes for Flat Head Socket Screws
~  More sizes than shown on this web page

Detailed Tapped Hole, C’Bore & C’Sink examples are shown in the images on this page.

Tapped Hole, C’Bore & C’Sink sizes included in PDF match these available screw sizes:
#0, #1, #2, #3, #4, #5, #6, #8, #10, 1/4, 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 3/4, 7/8, 1, 1-1/8, 1-1/4, 1-1/2, 1-3/4 & 2

Find out how to get a FREE !!! PDF copy of 3D Accuracy’s Tap, C’Bore & C’Sink Standards