Deburring galvanneal steel

What is the best way to deburr galvanneal steel after it has been punched at the turret. I prefer a grey wheel and others at work use a wire wheel which I think damages the plating. Or does it not matter if the part is painted?

The material you selected to make this part must have been selected for its special properties of corrosion resistance. If you mechanically alter that layer of coating you affect or compromise its resistance. However, if the part is to be painted there are definite advantages to roughen this surface. How much you roughen it depends on the paint and viscosity. In the aircraft industry they use a zinc chromate primer instead of a mechanical system before painting.