SAE (inch) Dimensions for Fasteners

TOLERANCES (Except Screw Length – See Screw Length Tolerances Below)

All dimensions in inches unless otherwise specified:

  • Two Place Decimal . . . . . . . .±.010
  • Three Place Decimal . . . . . .±.005
  • Fractions . . . . . . . . . . . . . . .±1/64″

Important Notes:

  • Up to 4″ long, all spacers and standoffs are kept to ±.005.
  • 4″ to 6″ long ±.008.
  • Over 6″ long ±.010.
  • SPECIAL CLOSE TOLERANCES are available.
    Just specify in the third stage of requesting a quote.
  • DIAMETER: Std Commercial Tolerances on bar & rod.
  • ROUND – COLD-FINISHED:
    • Under 5/16″ . . . . . . . . . . . . .±.001″
    • 5/16″ to 1/2″, incl. . . . . . . . . .±.0015
    • 1/2″ to 1″, incl. . . . . . . . . . . .±.002

THREAD INFORMATION

Thread Aluminum, Brass & Steel Nylon (‘L’) Stainless Steel (‘L’)
0-80 3/8 1/4
1-72 3/8 1/4
2-56 1/2 3/8
3-56 1/2 3/8
4-40 1 3/4
4-48 1 3/4
5-40 1 3/4
6-32 1 3/4
6-40 1 3/4
8-32 1 3/4
10-24 1 3/4
10-32 1 3/4
12-24 1 3/4
1/4-20 1 1/4 1 1/4
1/4-28 1 1/4 1 1/4
5/16-18 1 1/4 1 1/4
5/16-24 1 1/4 1 1/4
3/8-16 1 1/4 1 1/4
3/8-24 1 1/4 1 1/4
7/16-14 1 1/4 1 1/4
7/16-20 1 1/4 1 1/4
1/2-13 1 1/4 1 1/4
1/2-20 1 1/4 1 1/4

“Blind Tap Depths” when length ‘L’ IS LONGER THAN dimension shown in ‘Reference’ column below.

Thread Reference Length (all materials) Tap Depth
0-80 3/8 3/16
1-72 3/8 3/16
2-56 1/2 3/16
3-56 1/2 3/16
4-40 1/2 1/4
4-48 1 1/4
5-40 1 5/16
6-32 1 3/8
6-40 1 3/8
8-32 1 7/16
10-24 1 1/2
10-32 1 1/2
12-24 1 1/2
1/4-20 1 1/4 5/8
1/4-28 1 1/4 5/8
5/16-18 1 1/4 5/8<
5/16-24 1 1/4 5/8<
3/8-16 1 1/4 5/8
3/8-24 1 1/4 5/8
7/16-14 1 1/4 5/8
7/16-20 1 1/4 5/8
1/2-13 1 1/4 5/8
1/2-20 1 1/4 1 1/4

MACHINE SCREW SPECS

ECCENTRICITY

The heads of machine screws shall not be eccentric with the body beyond a tolerance of 3 percent of the maximum head diameter.

SCREWDRIVER SLOT DIMENSIONS

(Unless otherwise specified)

Max. OD Diameter
W (Max.)W (Min.)H (Max.)H (Min.)
Up to .160.031.023.030.022
.161 to .182.035.027.034.026
.183 to .204.039.031.038.030
.205 to .225.039.031.042.025
.226 to .269.048.039.053.033
.270 to .312.054.045.074.052
.313 to .413.060.050.080.057
.414 and up.075.064.111.083

SCREW LENGTH TOLERANCE (ALL EXCEPT Socket Head Cap Screws)

(Get Socket Head Cap Screw Specs and Tolerances Here)

Nominal Screw LengthLength Tol.Length Tol.
Nominal Screw Size0 – 121/4 – 3/4
Up to 1/2 in., incl.-0.02-0.03
Over 1/2 to 1 in., incl.-0.03-0.03
Over 1 to 2 in., incl.-0.06-0.06
Over 2 in.-0.09-0.09

LEAD POINT SCREWS ONLY

Nominal Screw LengthLength Tol.Length Tol.
Nominal Screw Size0 – 121/4 – 3/4
Up to 1/2 in., incl.-0.03-0.04
Over 1/2 to 1 in., incl.-0.04-0.04
Over 1 to 2 in., incl.-0.07-0.07
Over 2 in.-0.09-0.09

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