FLAT HEAD SELF TAPPING SCREW
Head Dimensions

82° Flat Head Self Tapping Screws 82° Undercut Flat Head Self Tapping Screws Square Drive Flat Head Self Tapping Screws Torx® Drive Flat Head Self Tapping Screws


Head Dimensions for 82° Flat Head Self-Tapping Screws
ANSI B18.6.4

Nominal Size These
Lengths or
Shorter are
Undercut
A H J T M R N F G Phillips
Driver
Size
Head
Dimensions
Slot Dimensions Phillips Dimensions Protrusion Above
Gaging Diameter
Gaging Diameter
Diameter Height Width Depth Dia Depth Width
Types
A and AB
Other
Types
Max Min Max Min Max Min Max Min Ref Ref Ref Max Min
0 3/16 1/8 .112 .096 .035 .026 .023 .016 .015 .010 .062 .035 .014 .026 .016 .078 0
1 3/16 5/32 .137 .120 .043 .033 .026 .019 .019 .012 .070 .043 .015 .028 .016 .101 0
2 3/16 3/16 .162 .144 .051 .040 .031 .023 .023 .015 .096 .055 .017 .029 .017 .124 1
4 1/4 1/4 .212 .191 .067 .055 .039 .031 .030 .020 .122 .081 .018 .032 .019 .172 1
5 1/4 1/4 .237 .215 .075 .062 .043 .035 .034 .022 .148 .074 .027 .034 .020 .196 2
6 5/16 5/16 .262 .238 .083 .069 .048 .039 .038 .024 .168 .094 .029 .036 .021 .220 2
7 3/8 3/8 .287 .262 .091 .076 .048 .039 .041 .027 .176 .102 .030 .037 .022 .243 2
8 7/16 7/16 .312 .285 .100 .084 .054 .045 .045 .029 .182 .110 .030 .039 .023 .267 2
10 1/2 1/2 .362 .333 .116 .098 .060 .050 .053 .034 .198 .124 .032 .042 .025 .313 2
12 9/16 9/16 .412 .380 .132 .112 .067 .056 .060 .039 .262 .144 .035 .045 .027 .362 3
14 5/8 - .462 .427 .148 .126 .075 .064 .068 .044 .276 .160 .036 .049 .029 .410 3
1/4 5/8 5/8 .477 .442 .153 .131 .075 .064 .070 .046 .276 .160 .036 .050 .029 .424 3
5/16 13/16 5/8 .597 .556 .191 .165 .084 .072 .088 .058 .358 .205 .061 .057 .034 .539 4
3/8 - 5/8 .717 .670 .230 .200 .094 .081 .106 .070 .386 .234 .065 .065 .039 .653 4
Note: The length of a flathead screw is always measured by the total length of the screw,
from the top of the head to the extreme end of the threads.


Head Dimensions for Undercut Flat Head Self Tapping Screws
ANSI B18.6.4

Nominal
Size
These
Lengths
or
Shorter
are
Undercut
A H J T M R N F G Phillips
Driver
Size
Head Dimensions Slot Dimensions Recess Dimensions Protrusion
Above Gaging
Diameter
Gaging
Diameter
Diameter Height Width Depth Dia Depth Width
Types
A and AB
Other
Types
Max Min Max Min Max Min Max Min Ref Ref Ref Max Min
0 3/16 1/8 .112 .096 .025 .018 .023 .016 .011 .007 .069 .035 .014 - - - 0
1 3/16 5/32 .137 .120 .031 .023 .026 .019 .014 .009 .070 .043 .015 - - - 0
2 3/16 3/16 .162 .144 .036 .028 .031 .023 .016 .011 .088 .048 .017 .029 .017 .124 1
4 1/4 1/4 .212 .191 .047 .038 .039 .031 .022 .014 .110 .070 .018 .032 .019 .172 1
6 5/16 5/16 .262 .238 .059 .048 .048 .039 .027 .017 .140 .066 .025 .036 .021 .220 2
7 3/8 3/8 .287 .262 .064 .053 .048 .039 .030 .019 .148 .074 .027 .037 .022 .243 2
8 7/16 7/16 .312 .285 .070 .058 .054 .045 .032 .021 .168 .094 .029 .039 .023 .267 2
10 1/2 1/2 .362 .333 .081 .068 .060 .050 .037 .024 .182 .110 .030 .042 .025 .313 2
12 9/16 9/16 .412 .380 .092 .078 .067 .056 .043 .028 .226 .110 .030 .045 .027 .362 3
1/4 5/8 5/8 .477 .442 .107 .092 .075 .064 .050 .032 .244 .124 .032 .050 .029 .424 3
5/16 13/16 5/8 .597 .556 .134 .116 .084 .072 .062 .041 .310 .157 .053 .057 .034 .539 4
3/8 - 5/8 .717 .670 .161 .140 .094 .081 .075 .049 .358 .205 .061 .065 .039 .653 4
Note: The length of a flathead screw is always measured by the total length of the screw,
the top of the head to the extreme end of the threads.


Head Dimensions for Square Drive Flat Head Self Tapping Screws - IFI

Nominal Size
Or
Basic Screw
Diameter
A M T Driver
Size
F
Head Diameter Recess Square Recess Depth Gauge
Penetration
Max Min Max Min Max Min Max Min
4 .1120 .212 .191 .071 .0696 .073 .063 0 .038 .032
6 .1380 .262 .238 .091 .090 .113 .105 1 .065 .057
8 .1640 .312 .285 .1126 .111 .140 .119 2 .075 .065
10 .1900 .362 .333 .1126 .111 .140 .119 2 .075 .065
12 .2160 .412 .380 .133 .1315 .165 .155 3 .095 .085
1/4 .2500 .477 .442 .133 .1315 .165 .155 3 .095 .085
5/16 .3125 .597 .556 .191 .1895 .201 .191 4 .100 .090
The recess has a square center opening, slightly tapered side walls and a conical bottom.
Note: The length of a flathead screw is always measured by the total length of the screw,
the top of the head to the extreme end of the threads.


Head Dimensions for Torx® Drive Flat Head
Self Tapping Screws - Camcar

Nominal Size G T B F Maximum
Penetration
of "No-Go"
Gauge
(Fallawat)
Torx®
Driver
Size
Head Diameter Head Height Recess
Diameter
Gauge
Penetration
Max Sharp Min Sharp Abs Min Ref Ref Min
4 .225 .209 .195 .067 .094 .028 .019 T8
6 .279 .257 .244 .083 .111 .035 .022 T10
8 .332 .308 .282 .100 .132 .040 .026 T15
10 .385 .359 .340 .116 .155 .050 .031 T20
1/4 .507 .447 .452 .153 .200 .075 .040 T27




Smith Fastener Company • 3613 East Florence Avenue, Bell, California, 90201
Phone: ( 323 ) 587-0382 • FAX: ( 323 ) 587-8712 • E-mail: [email protected]
Copyright © 2009 by Smith Fastener Company

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