Glossary

A circular elastomer seal, shaped like a ring, used to prevent the leakage of fluids or gases between two joined parts. O-rings are commonly seated in a groove and compressed between surfaces, providing an effective and simple sealing solution in hydraulic, pneumatic, and mechanical systems.

An ogee washer is a heavy-duty washer with a thick, curved (S-profile/“ogee”) face and a large bearing surface. Typically cast or malleable iron—often hot-dip galvanized—it sits under a nut or bolt head to spread load over wood and resist crushing or pull-through.

You’ll see them in timber framing, docks, bridges, utility/pole line work, and other structural wood connections where a standard flat washer is too small. The ogee contour lets the washer seat firmly on uneven wood and provides a traditional look. They’re sometimes called malleable iron ogee washers, cast ogee washers, or timber washers.

Fastener oxidization is the chemical reaction between a fastener’s metal surface and oxygen, often accelerated by moisture, salt, or other corrosive elements. Depending on the material, oxidation can either protect or damage the fastener: steel and iron form iron oxide (rust), which weakens and flakes; stainless steel develops a thin chromium oxide layer that prevents deeper corrosion; aluminum creates a hard aluminum oxide layer that protects the base metal; and zinc coatings form zinc oxide, which acts as a sacrificial barrier for the steel underneath. Uncontrolled oxidation can reduce strength, seize threads, and shorten service life, which is why protective coatings, plating, and corrosion-resistant alloys are widely used in the fastener industry.