The tables below provide general information on the tolerances of wire, rod and bar.
The tolerances are based on published standards used throughout the industry.
Diameter — Round Wire And Rod, Cold Finished
| Tolerance In Inches | |||||
| Specified Diameter In Inches |
Drawn Wire | Cold Finished Rod | Rolled Rod | ||
| Over or Under | Over | Under | |||
| >= 0.125 | <= 0.374 | ± 0.0015 | - | - | - |
| >= 0.375 | <= 0.500 | - | ± 0.0015 | - | - |
| >= 0.501 | <= 1.000 | - | ± 0.002 | - | - |
| >= 1.001 | <= 1.500 | - | ± 0.0025 | - | - |
| >= 1.501 | <= 2.000 | - | ± 0.004 | + 0.006 | - 0.006 |
| >= 2.001 | <= 3.000 | - | ± 0.008 | + 0.008 | - |
| >= 3.001 | <= 3.499 | - | ± 0.008 | + 0.012 | - 0.012 |
| >= 3.500 | <= 5.000 | - | ± 0.008 | + 0.012 | - 0.012 |
| >= 5.001 | <= 8.000 | - | - | + 0.062 | - 0.031 |
Distance Across Flats — Square Or Hex Bar, Cold Finished
| Specified Distance Across Flats | Tolerance In Inches | |
| >= 0.375 | <= 0.500 | ± 0.002 |
| >= 0.501 | <= 1.000 | ± 0.0025 |
| >= 1.001 | <= 1.500 | ± 0.003 |
| >= 1.501 | <= 2.000 | ± 0.005 |
| >= 2.001 | <= 3.000 | ± 0.008 |
Diameter Or Distance Across Flats —
Round, Hex, Square Or Rectangular Rod And Bar, Extruded
| Specified Size | Tolerance In Inches | |
| >= 0.250 | <= 0.499 | ± 0.008 |
| >= 0.500 | <= 0.749 | ± 0.009 |
| >= 0.750 | <= 0.999 | ± 0.010 |
| >= 1.000 | <= 1.499 | ± 0.012 |
| >= 1.500 | <= 1.999 | ± 0.014 |
| >= 2.000 | <= 3.999 | ± 0.024 |
| >= 4.900 | <= 5.999 | ± 0.034 |
| >= 6.000 | <= 7.999 | ± 0.044 |
| >= 8.000 | - | ± 0.054 |
Diameter — Class I Forging Stock
| Tolerance In Inches | |||
| Specified Diameter | Allowable Deviation | Conditioning Allowance | |
| >= 0.375 | <= 3.000 | ± 0.015 | - 1/32 |
| >= 3.001 | <= 5.000 | ± 0.031 | - 1/16 |
| >= 5.001 | <= 8.000 | ± 0.063 | - 1/16 |
Diameter — Class II Forging Stock
| Tolerance In Inches | ||
| Specified Diameter | Allowable Deviation | |
| >= 0.375 | <= 0.500 | ± 0.015 |
| >= 0.501 | <= 1.000 | ± 0.002 |
| >= 1.001 | <= 1.500 | ± 0.025 |
| >= 1.501 | <= 3.000 | ± 0.008 |
Thickness And Width — Rectangular Bar, Cold Finished
| Tolerance In Inches | |||
| Specified Dimension | Thickness | Width | |
| >= 0.125 | <= 0.500 | ± 0.002 | ± 0.002 |
| >= 0.501 | <= 1.000 | ± 0.0025 | ± 0.0025 |
| >= 1.001 | <= 1.500 | ± 0.003 | ± 0.003 |
| >= 1.501 | <= 2.000 | ± 0.005 | ± 0.005 |
| >= 2.001 | <= 3.000 | ± 0.008 | ± 0.008 |
| >= 3.001 | <= 4.000 | - | ± 0.010 |
Twist — Square Or Rectangular Bar, Cold Finished
All Tempers Except T351, T651, T7351
Allowable twist per segment length is based on deviation in total length or deviation in any measured segment of one foot or more, expressed in degrees per foot of segment length. Maximum is deviation in total length of material.
| Twist Tolerance | |||
| Specified Width | Segment Length | Maximum | |
| - | <= 1.499 | 1º X length | 7º |
| >= 1.500 | <= 2.999 | 0.5º X length | 5º |
| >= 3.000 | - | 0.25º X length | 3º |
Twist — Square Or Rectangular Bar, Cold Finished
Tempers T531, T651, T7351
Allowable twist per segment length is based on deviation in total length or deviation in any measured segment of one foot or more, expressed in degrees per foot of segment length. Maximum is deviation in total length of material.
| Twist Tolerance | |||
| Specified Width | Segment Length | Maximum | |
| >= 0.500 | <= 2.999 | 1.5º X length | 7º |
| >= 3.000 | - | 0.5º X length | 5º |
Twist — Hexagonal Bar, Cold Finished
Allowable twist per segment length is based on deviation in total length or deviation in any measured segment of one foot or more, expressed in degrees per foot of segment length. Maximum is deviation in total length of material.
| Twist Tolerance | |||
| Specified Width Across Flats | Segment Length | Maximum | |
| - | <= 1.499 | 1º X length | 7º |
| >= 1.500 | <= 2.999 | 0.5º X length | 5º |
| >= 3.000 | - | 0.25º X length | 3º |
Straightness — Rod Or Hex Bar Other Than Screw Machine Stock
All Tempers Except T531, T651, T7351
Tolerances are expressed in inches per total length or inches in any measured segment of at least one foot or more. Specified dimension is diameter or distance across flats.
| Tolerance In Inches | |
| Specified Dimension | Segment Deviation |
| All | 0.25 X length |
Straightness — Rod Or Hex Bar Other Than Screw Machine Stock
Tempers T531, T651, T7351
Tolerances are expressed in inches per total length or inches in any measured segment of at least one foot or more. Specified dimension is diameter or distance across flats.
| Tolerance In Inches | ||
| Specified Dimension | Segment Deviation | |
| >= 0.500 | - | 0.25 X length |
Straightness — Square or Rectangular Bar Other Than Screw Machine Stock
All Tempers Except T531, T651, T7351
Tolerances are expressed in inches per total length or inches in any measured segment of at least one foot or more. Specified dimension is thickness or distance across flats.
| Tolerance In Inches | |
| Specified Dimension | Segment Deviation |
| All | 0.25 X length |
Straightness — Square or Rectangular Bar Other Than Screw Machine Stock
Tempers T531, T651, T7351
Tolerances are expressed in inches per total length or inches in any measured segment of at least one foot or more. Specified dimension is thickness or distance across flats.
| Tolerance In Inches | ||
| Specified Dimension | Segment Deviation | |
| >= 0.500 | - | 0.5 X length |
Straightness — Screw Machine Stock, Cold Finished
All Tempers Except T531, T651, T7351
Segment tolerances are expressed in inches per total length or inches in any measured segment of at least one foot or more. Length tolerances are deviations in inches per 12-foot length. Specified dimension is thickness or distance across flats.
| Tolerance In Inches | ||
| Specified Dimension | Segment Deviation | Length Deviation |
| All | 0.125 X length | 0.100 |
Straightness — Screw Machine Stock, Cold Finished
Tempers T531, T651, T7351
Segment tolerances are expressed in inches per total length or inches in any measured segment of at least one foot or more. Length tolerances are deviations in inches per 12-foot length. Specified dimension is thickness or distance across flats.
| Tolerance In Inches | |||
| Specified Dimension | Segment Deviation | Length Deviation | |
| >= 0.500 | - | 0.125 X length | 0.100 |
Length
Specified dimension is diameter, width or width across flats.
| Tolerance In Inches Per Length In Feet | |||||
| Specified Dimension | Up to 12' | 12' - 30' | 30' - 50' | > 50' | |
| - | <= 2.999 | 1/8 | 1/4 | 3/8 | 1 |
| >= 3.000 | <= 7.999 | 3/16 | 5/16 | 7/16 | 1 |
| >= 8.000 | - | 1/4 | 3/8 | 1/2 | 1 |
Flatness — Cold Finished Bar
| Tolerance In Inches | |
| Surface Width In Inches | Segment Deviation |
| Up to 1 | .004 |
| Over 1 | .004 X Width |
| In any 1 inch of width | .004 |
Squareness Of Saw Cuts
Angularity