Sharp Edges
Sharp edges are commonly caused by laser, water and plasma cutting of steel.
Sharp edges have been shown to cause fracturing of the zinc and localised thinning of the powder coating around the edge for up to 10mm.
The sharp edges should be “broken” by either (a)champhering the edge (good) or (b)making a 5mm radius (best) to allow the zinc and powder coating to grow and flow around the edge. An additional benefit of champhering the edges is that they are much more comfortable to handle and safer in use especially in balustrade components
The result of laser cut profile, galvanized and fettled. The zinc has fractured to allow rust to start from the sharp edge
Similar problems can occur on glass washers.
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