Hardened Steel
- The strongest and most economical. It does however vary greatly in specification and quality.
- Made from 1018 - 1022 steel wire drawn, cold formed and then heat treated. For maximum strength it is heat treated to a core hardness of Rockwell C28-38 and a case hardness of Rockwell C45 min., this gives high strength without brittleness.
- The standard finish is "Lube" which has a bronze/Grey colour. The colour of the screw comes from the heat treatment after which a dry wax is applied to prevent corrosion and ease driving.
- It is ideal for furniture however for exterior work you will at least need Zinc plating.
- Seaside applications are very severe and salt air will eat plating, in these situations use Stainless.
- Chemicals in treated pine are also very corrosive and stainless is best but mechanical zinc plating is the next best alternative as it has far greater corrosion resistance than normal zinc plating.
Stainless Steel
Silicon Bronze
- Specially developed for marine work below the water line of boats
- Offers superior corrosion resistance (even with dissimilar metals) and prevents rot around the screw.
- It is not as strong as stainless but has superior corrosion resistance and does not become brittle.
Brass
- Great for classical furniture, it really looks lovely against brass fittings and hinges
- Very soft and needs to be used with great care.
- Very expensive but for that family heirloom it is well worth the investment.
