Fastener Knowledge

Grade 2, Grade 5 and Grade 8 are divided by the joint, not by the industry. What each grade is used for, what rules it out, and what the order still has to carry.

Grade 8 outranks Grade 5 and Grade 2 on strength, but the joint decides which grade is right. How the three grades differ, where each fits, and what changes when one is substituted.

Hammer drive anchors are set for good, but the fixture, the surface or the hole can still be recovered. The methods, their limits, and the damage each one leaves behind.

J429 fixes a bolt's steel and strength, not its shape. What Grade 2, 5 and 8 actually specify, where the standard stops, and what the order has to add.

Carriage, elevator and step bolts share a square neck but not a head. How head profile, head size and length basis decide which one a joint needs.