Washers

Washers provide a greater bearing surface under the fastener. This helps prevent a nut, bolt or screw from pulling through the material.

Available types and materials:

 

Flat washers

Used under the head of a bolt or nut to distribute the forces applied when tightening.   Brass An alloy of copper with good corrosion resistance. Once common for marine use brass is now used mostly in decorative applications. Stainless steel 18-8 Stainless steel 18-8 is an alloy of steel with high corrosion resistance. Stainless has become the material of choice for exterior and most marine applications. Silicon Bronze Bronze is an alloy of copper with greater strength and corrosion resistance than brass. Most commonly used in wood boat building and restoration.

USS flat washers

Used under the head of a bolt or nut to distribute the forces applied when tightening. USS pattern is the most common type of flat washer.   Zinc plated steel Steel is zinc plated for moderate protection against rust. Steel grade 8 Made from tempered medium carbon alloy steel and zinc plated. Best for applications where high strength and hardness is required. Hot dipped galvanized Hot dipped galvanized fasteners are much more corrosion resistant than zinc plated fasteners. Due to the thickness of the galvanized coating, galvanized bolts will only work with galvanized nuts. For exterior and coastal area use. (ASTM A153)

SAE flat washers
Used under the head of a bolt or nut to distribute the forces applied when tightening. SAE pattern is a tighter fit on the bolt and a smaller outside diameter.   Zinc plated steel Steel is zinc plated for moderate protection against rust. Steel grade 8 Made from tempered medium carbon alloy steel and zinc plated. Best for applications where high strength and hardness is required.

Fender washers
Used under the head of a bolt or nut to distribute the forces applied when tightening. Fender washers have a large outside diameter. Zinc plated steel Steel is zinc plated for moderate protection against rust. Stainless steel 18-8 Stainless steel 18-8 is an alloy of steel with high corrosion resistance. Stainless has become the material of choice for exterior and most marine applications.

Lock washers

Lock washers place tension against a nut after tightening, to help prevent the nut from loosening.   Zinc plated steel Steel is zinc plated for moderate protection against rust. Steel grade 8 Made from tempered medium carbon alloy steel and zinc plated. Best for applications where high strength and hardness is required. Stainless steel 18-8 Stainless steel 18-8 is an alloy of steel with high corrosion resistance. Stainless has become the material of choice for exterior and most marine applications. Silicon Bronze Bronze is an alloy of copper with greater strength and corrosion resistance than brass. Most commonly used in wood boat building and restoration. Hot dipped galvanized Hot dipped galvanized fasteners are much more corrosion resistant than zinc plated fasteners. Due to the thickness of the galvanized coating, galvanized bolts will only work with galvanized nuts. For exterior and coastal area use. (ASTM A153)

Lock washers external tooth
Uses external teeth for locking and tension.   Zinc plated steel Steel is zinc plated for moderate protection against rust. Stainless steel 410 A stainless alloy harder than the 18-8, but not as resistant to corrosion as 18-8.

Lock washers internal tooth
Uses internal teeth for locking and tension. Less aggressive than external tooth with a smaller outside diameter.   Zinc plated steel Steel is zinc plated for moderate protection against rust. Stainless steel 410 A stainless alloy harder than the 18-8, but not as resistant to corrosion as 18-8.

Finishing washers

Made for flat or oval head screws for a finished look.   Brass An alloy of copper with good corrosion resistance. Once common for marine use brass is now used mostly in decorative applications. Nickel plated steel Steel that is nickel plated for appearance. Stainless steel 18-8 Stainless steel 18-8 is an alloy of steel with high corrosion resistance. Stainless has become the material of choice for exterior and most marine applications. Silicon Bronze Bronze is an alloy of copper with greater strength and corrosion resistance than brass. Most commonly used in wood boat building and restoration.

Dock washers
Used to distribute the forces applied when tightening. Dock washers have a larger outside diameter than standard and are thicker than standard.   Hot dipped galvanized Hot dipped galvanized washers are much more corrosion resistant than zinc plated washers. For exterior and coastal area use. (ASTM A153)

Square dock washers
Used to distribute the forces applied when tightening. Square dock washers have a large square outside and are thicker than standard washers.   Hot dipped galvanized Hot dipped galvanized washers are much more corrosion resistant than zinc plated washers. For exterior and coastal area use. (ASTM A153)

Ogee washers
Ogee washers are thick, large diameter, cast iron washers. They have a curved or sculpted appearance and are typically used in dock and wood construction to prevent bolt heads and nuts from pulling into the wood.   Hot dipped galvanized Hot dipped galvanized washers are much more corrosion resistant than zinc plated washers. For exterior and coastal area use. (ASTM A153)