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Shining up hot dip galvanizing for architectural use

we have shipped hot dipped galvanized steel window units to a local school district....they have seen some other hot dipped galvanized windows with a brighter almost polished finish..
we are now left with trying to shine up the "installed" window units to suit the architect and school district requirements....

what will brighten the units and how could this be accomplished?

Don Moyer
plant manager, torrance aluminum windows - Perris, California, USA
February 3, 2011

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February 4, 2011

To get "bright" galvanizing mostly requires a little aluminium in the molten zinc.
But even when bright from the beginning, all galvanizing goes dull grey with time. This is because zinc is reacting with air etc and forming a layer of zinc oxides and carbonates on the surface. Its this layer that protects zinc (and the zinc that protects the steel).

When specifying these windows did the architect specify brightness? Or any standard for the galvanizing? Or has this requirement for brightness been introduced afterward?
The international standard for galvanizing, ISO 1461 doesn't specify brightness.
Those that understand what galvanizing really is would not specify brightness, knowing its only temporary.

Shining up the galv, by polishing or something like that will only give a temporary effect.
If long lasting brightness is required, then galvanizing is the wrong spec.

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK