Hot Dip Galvanized v.Electro-Galvanized Nails

Metallurgy expert describes the difference between hot dip galvanized nails and electro-galvanized nails. Manufacturers have changed from hot dip galvanizing to electro-galvanizing. The zinc is a sacraficial materail; therefore, the protection afforded by the galvanize layer (zinc) depends on the zinc thickness. All other things being equal, the electro-galvanized nails with the much thinner zinc layer (t= 0.000065"), right photo, will rust sooner than the hot dip galvanized (t= 0.0015"), left photo. It is reccomended that hot dipped nails be used for critical applications.