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Question: Can I use a hot-dip galvanized nut on a plain finish bolt?

Answer: Hot-dip galvanized nuts cannot be used on a plain finish bolt.

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Question: Can high strength bolts be hot-dip galvanized?

Answer: Some high strength bolts can be galvanized while others cannot. Read More...

Question: Are current ASTM galvanizing standards suitable for use with the new chemicals being used in pressure treated wood? Some people have told me I need to use double or triple dipped fasteners. Is this true?

Answer: Since the new chemicals (alkaline copper quat [ACQ], copper azole [CBA-A and CA-B], and sodium borates [SBX]) now being used in pressure treated wood have been shown to be up to two or three times more corrosive then the previously used chromate copper arsenate (CCA), the recommended galvanizing thickness for materials being used with the new pressure treated wood was increased from about 0.75 to 1.56 mils thick. Read More...

Question: Can threads be chased after hot-dip galvanizing for proper nut fit? Answer: Absolutely not! Externally threaded fasteners should never be “chased”. During the hot-dip galvanizing process, excess zinc has a tendency to build up in the threaded portion of a fastener. Chasing threads is a term used to describe re-cutting threads after galvanizing to remove this excess zinc gained during the galvanizing process. Chasing threads will not only remove the excess zinc, but often remove much, if not all of zinc coating and eliminates the corrosion protection on the threaded portion of the fastener. Read More...

Question: How much weight is gained from hot-dip galvanizing bolts?

Answer: According to the American Galvanizers Association (AGA) the weight of an item on average will increase about 3.5% from the zinc added during the galvanizing process. Read More...

A summary of corrosion resistant coating options for high strength bolts. Bolts with an ultimate tensile strength higher than 150 ksi can not be hot-dip galvanized. Here are some alternatives. Read More...

Can zinc plated nuts be used on hot-dip galvanized rods? Read More...