Carriage bolts are typically made from steel, stainless steel, or zinc-plated steel. Steel bolts are known for their strength but may require protective coatings to resist corrosion. Stainless steel carriage bolts are highly corrosion-resistant, making them ideal for outdoor or marine environments where moisture is a factor. Zinc plating provides moderate corrosion resistance and is commonly used for bolts intended for indoor or less corrosive applications.

Carriage bolts are available in various diameters and lengths to accommodate different applications. Common diameters range from 1/4 inch to 1 inch, and lengths can range from under an inch to over a foot, depending on requirements. Standard measurements are typically in both metric and imperial units, allowing for compatibility in international projects. The appropriate size depends on the thickness of the materials being joined and the level of load required.

Carriage bolts provide a flush, tamper-resistant appearance due to their rounded heads, which is useful for safety and aesthetics. The square neck prevents the bolt from spinning when tightened, allowing for easy installation with a single tool on the nut side. They are also highly durable, making them ideal for structural applications that require secure fastening. Additionally, carriage bolts distribute force evenly, reducing the risk of material damage.

Carriage bolts are measured by their diameter and length. The diameter is the width of the threaded shaft, and the length is measured from the top of the square shoulder to the end of the threaded part, excluding the domed head. It’s essential to choose the correct diameter and length for your application to ensure a secure fit and optimal performance.