The number 1 or number larger than one, or number one or number larger than one followed by a fraction, is the diameter of the shaft. The number following the hyphen is the number of threads per inch; that is, the number of threads on the shaft itself, per inch of shaft length. Same as for smaller parts.
What does #12 mean on a screw?
The number “12” is used as a size designator with no numerical meaning. “24” references the 24 threads per inch. You can identify a 12-24 screw by measuring the diameter with a ruler at slightly less than 7/32 inches (5.6mm).
A typical rule of thumb . . . Use a bolt diameter that is 1.5 2.5 times (up to three times) the thickness of the thinner material you are bolting together. So, for 1/8″ material, a 1/4″ diameter is often a good bolt choice. For 1/4″ thick material, perhaps a 3/8″ or 1/2″ bolt.
For fasteners where the head usually sits above the surface, the measurement is from directly under the head to the end of the fastener. For fasteners that are designed to be countersunk, the measurement is made from the point on the head where the surface of the material is, to the end of the fastener.
How much stronger is grade 8 than Grade 5?
Grade 8 Bolts A grade 8 bolt is the highest grade SAE bolt. Grade 8 bolts have a minimum tensile strength of 150,000 PSI. As a comparison, the ASTM A325ASTM A325ASTM A325 is an ASTM International standard for heavy hex structural bolts, titled Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength. It defines mechanical properties for bolts that range from 1⁄2 to 11⁄2 inches (13 to 38 mm) in diameter.https://en.wikipedia.org › wiki › ASTM_A325ASTM A325 - Wikipedia bolt is roughly equivalent to the SAE grade 5. A grade 8 bolt would be one that meets ASTM A490 standards.Jun 5, 2020
Which is stronger 8.8 or Grade 5?
Grade/Class Strength
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Grade 5 Medium strength.
Grade 8 High strength.
Metric Class 4 Similar to Grade 2.
Metric Class 8.8 Similar to Grade 5.
Are Grade 8 bolts or Grade 5 shear easier?
There exists an often quoted myth, that Grade 5 bolts are better in shear than Grade 8 since they will bend before breaking. Not true. Shear strength of alloy steel is approximately 60% of its ultimate tensile strength.