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 Length | Length Tol. | Length Tol. |
| Nominal Screw Size | 0 – 12 | 1/4 – 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 Length | Length Tol. | Length Tol. |
| Nominal Screw Size | 0 – 12 | 1/4 – 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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