Fin Neck Bolt We also manufacture Fin Neck Bolt in grade 8.8, A307, 4.8, in finish HDG, Yellow & GI. fin neck bolt mostly used in steel railing, timber/wood work. Also Called LOCKING BOLTS. Fin Neck bolts lock into steel or wood surfaces to assist one man bolt tightening. Available in either Pan Head or Round Head. These are threaded full length to the base of the fins.

General:

Primarily used in thin plywood to keep the bolt from turning when nut is being tightened. It lock into steel or wood surfaces to assist bolt tightening, ASME B18. The fasteners are most commonly made from low carbon steel material. It feature a round head and a flat bearing surface. The bearing surface of these bolts makes a 90° angle with the shank. The bolts are mainly used in thin plywood, common size is 1/2”x3/4” and M12x25 M12x35. It is distinguished from other bolts by its shallow mushroom head and the fact that the cross-section of the shank, though circular for most of its length (as in other kinds of bolt), is square immediately beneath the head. This makes the bolt self-locking when it is placed through a square hole in a metal strap. This allows the fastener to be installed with only one tool, a spanner or wrench, working from one side. The head of a carriage bolt usually is a shallow dome. The shank has no threads; and its diameter equals the side of the square cross-section.