Boatbuilding occasionally reminds us that the correct solution to a problem is not always evident. Many people have asked, which sort of fastener is the best: galvanized, bronze, or stainless steel. The scarcity of readily available bronze against the widely available stainless complicates the situation.
If you are looking for Marine Bronze Fasteners then the website of Fair Wind Fasteners can be the best choice available.
Bronze is equally as robust as stainless steel, but it is softer to touch. This implies that components of either material can be made to the same requirements, making them replaceable on the same boat.
Their working and breakdown loads for almost the same size component will be near enough that they can still be used interchangeably structurally.
Let us try to highlight the differences between these two materials:
Stainless steel is attacked if it is immersed in an enclosed space in a liquid with chlorine or some other ions (salt water, fresh water contaminants, and solutes from the wood itself).
The oxygen in the solution depletes before the other ions, causing the metal to erode swiftly and completely.
Below the water level and for through-hull fastenings, bronze is the material of choice, whereas stainless steel can be used above the water level where the joint can dry out and oxygen can be replaced.
While high-quality stainless materials that resist assault are available, they are difficult to come by for the average person, whether from a maritime supplier or a local hardware store. Furthermore, they are high-priced items.
While bronze is not soft enough for cushioning the blow if you stub your toe on a deck component, it is soft enough to prevent fracture when overloaded.
Both materials perform in the same way on your yacht under typical loads. When the 2 materials will be pushed to their breaking point, the difference becomes apparent.
Because stainless steel is tougher than bronze, it will maintain its shape until it splits. The metal loses all of its strength once it cracks, and the component may fail catastrophically!
Bronze, on the other hand, is softer compared to Stainless Steel and will not crack and fail at the same time. Instead, it will slightly distort, bend, or stretch.
It is now weaker, yet it continues to work at a reduced level. This means that even if a bronze component will be pushed to its limit, it may not fail catastrophically.
Galvanized steel is a low-cost option, but nicking or wearing through the zinc covering may cause the steel to rust. It is far simpler to buy a few different sizes of bolts, then cut them to length as required rather than stocking all of the different sizes, and galvanized lacks this choice.
When we talk about galvanized, we usually mean hot dipped (rough). Galvanized “deck screws” (smooth and shiny) from the home center are ineligible. Those that did make it out were heavily corroded and necked.
Despite all the differences and similarities bronze material still remains the favorite for any boat project.