of screws and bolts could be produced in a shorter amount of time, and with more consistency and precision. By the mid 1700 s, the Wyatt brothers in England were manufacturing 150,000... wooden screws a week. Across the pond in America, several companies were making fasteners by the late 1700 s. However, there was no standard for size or thread density from... into the modern age: the Civil War. It brought with it a huge demand for machinery, and by extension, screws, nuts, and bolts. It was during this period that the need for developing...

with no defined correlation. Heat Number/Heat Lot This number is generated from the mills that melt the raw material used in screws/nuts/bolts. This number follows the fastener through its life... A Typically refers to standard sheet metal screw points. Sharp point, fewer threads and deeper than a type AB sheet metal screw. A standard off the shelf sheet metal screw in 18-8..., some 316ss and carbon steel. Type AB Sharp point, finer thread than a type A , thread dimensions similar to a type B sheet metal screw. Not a common thread in stainless steel...