Touch Up Methods
It seems more customers are requesting I touch-up imperfections in the galvanized coating with a zinc hot spray, i.e. metallizing, which I do not offer as a service. What is driving those requests, and how should I comply?
There are at least two possible sources behind the increase in requests for metallizing, one rooted in technical issues and another in marketing savvy. The first may result from a specifiers logical but rudimentary scientific conclusion-the more zinc the better. Since metallizing is 100% zinc metal, the specifier assumes it must be better than applying a paint containing zinc dust with 65%-69% or above 92% zinc in dry film as specified in ASTM A780. Because the HDG industry promotes the use of zinc with phrases such as, performance and durability are linearly related to the coating thickness, i.e. the thicker the coating the better, this is an understandable conclusion. However, comparing zinc-rich paint and metallizing, the strength of the bond, different repair coating thicknesses, and other factors dont make such a conclusion cut and dry.
The second source of the requests may be coming from those with a specific interest in metallizing either companies exclusively in the business who would like to see everything metallized and not galvanized or painted or other galvanizers who have small metallizing units to repair using hot zinc spray, giving them a competitive advantage. The conundrum in all of this involves informing the customer you prefer to and only provide touchup using zinc-rich paint when they think metallizing is the best f the touch-up methods. Perception is your customers reality! There are two clear paths to resolution and retaining your customer: (1) explain how ASTM A780 allows for zinc-rich paint, metallizing, and zinc solder touch-up and repair, and does not make a claim one performs better than another. Also, zinc-rich paints are used overwhelmingly by the galvanizing industry and have been for many years, or (2) purchase a small, hot-metal spray unit and offer touch up and repair to this customer and to all other customers.
A premium on the metallizing method may be in order. Should the purchase of a $20,000 or more piece of equipment not be in your business plan, you can satisfy the persistent customer by hiring a local metallizer to come to your plant to make the necessary repair. While such providers are not always well known, you may find one by doing a simple search on Google using terms like metallizing, thermal spray metallizing, or flame spray metallizing, and your city. If you cannot find a metallizer in your city, you can do the search without inputting your city to find a metallizer in a neighboring city.
© 2021 American Galvanizers Association. The material provided herein has been developed to provide accurate and authoritative information about after-fabrication hot-dip galvanized steel. This material provides general information only and is not intended as a substitute for competent professional examination and verification as to suitability and applicability. The information provided herein is not intended as a representation or warranty on the part of the AGA. Anyone making use of this information assumes all liability arising from such use.