I have a ZnCl2 based kit and am having difficulty getting an even spread of plate on a motorcyle centre stand spring. The spring is 3 inches long and 3/4 inch in diameter. It has a hook on each end.
After cleaning, degreasing and pickling I have proceeded to suspend the spring in the solution by running a copper wire down the centre of the spring. The problem is that each of the hoods either end get too much current and get a very rough coating. Then the plating stops where the hook bends into the spring coil, with no plating but a grey colour on the main coils of the spring. If a place one of the Zinc anodes right next to the coils that local area gets some plating.
I calculated my area as 7.3 inches plus the inside of the spring. I am running at about 1 amp and works out at 1.4 volts at 75F temperature.
I'm wondering if my solution does not contain enough Zinc Chloride and if this would give this result of too much current at the ends and none in the middle of the spring.
Just done some research online and found this.
http://journals.tubitak.gov.tr/chem/issues/kim-02-26-5/kim-26-5-11-0108-10.pdf
Im using only 50g/litre of Ammonium Chloride and I should be nearer 200 g/litre.
My ZnCl2 is about right at 50g/litre.
pH is about 4.
Going to try more Ammonium Chloride and see if this was the problem.
After cleaning, degreasing and pickling I have proceeded to suspend the spring in the solution by running a copper wire down the centre of the spring. The problem is that each of the hoods either end get too much current and get a very rough coating. Then the plating stops where the hook bends into the spring coil, with no plating but a grey colour on the main coils of the spring. If a place one of the Zinc anodes right next to the coils that local area gets some plating.
I calculated my area as 7.3 inches plus the inside of the spring. I am running at about 1 amp and works out at 1.4 volts at 75F temperature.
I'm wondering if my solution does not contain enough Zinc Chloride and if this would give this result of too much current at the ends and none in the middle of the spring.
Just done some research online and found this.
http://journals.tubitak.gov.tr/chem/issues/kim-02-26-5/kim-26-5-11-0108-10.pdf
Im using only 50g/litre of Ammonium Chloride and I should be nearer 200 g/litre.
My ZnCl2 is about right at 50g/litre.
pH is about 4.
Going to try more Ammonium Chloride and see if this was the problem.
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