Quote:
Originally Posted by Mike H
The Staffs badge was anodised on Zinc and is really heavy. Much more than a new metal badge let alone aluminium.
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Hi Mike,
All anodised means is oxidised. Not sure how zink is coloured (German WWII zink badges were usually plated with the plating repelled by the zink over time). The Staffs badge may well have been zink and could have been coloured by dye as per A/A badges or plated as per modern ones - I have no idea?
Aluminium is anodised (oxidised) in its natural state as soon as it is refined and exposed to air. The badge manufacturers simply increased the natural thickness of an anodic crust to the aluminium to provide a hardened crust to the aluminium metal to protect it. Therefore, anodising has absolutely nothing to do with colouring the aluminium metal.
Aluminium oxide or if you prefer anodised aluminium, is also very porous thus allowing it to take up the colour dye used to give the badge its colour as we see in A/A badges.
So 'staybrite' cap badges were anodised to:
a) provided a protecting crust to the aluminium
b) provide a medium that allowed the badges to be coloured by a liquid dye.
Regards,
Chris