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Problem in ABS Plating

2002

Dear sir,

We are experiencing a problem on Plating on ABS ,there is a few pits in a corner of the job (at the particular spot) .We are using the following sequence:-

1) Soak cleaning
2) Etching
3) Preactivation
4) Activation
5) Postactivation
6) Electroless Nickel
7) Dijigging
8) Acid Copper
9) Bright Nickel
10) Bright Chrome

Please let us know if Polishing the component will help in eliminating this problem or if the sequence need to be modified or is there any need for special attention in any of the above steps .

Thanks in advance,

Manish Singh
- Kandivli, Maharashtra, India

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Your process seems to be OK. You have to work as a detector in order to find out at what step the pits start. If they are observed on the corner of the parts only (meaning high current density) then I will bet on the nickel. But you have to take out parts after the copper and make sure that there are no pits on it. If this is the case, maybe the only thing you need is more anti pitting agent (wetter) in the nickel. This is true only if the pits apear on the HCD. Take a good look, maybe the pits are on the upper side of the parts which means that you have to filter the solution. Try these recommendations and if it did not help, get back and I will try some more ideas.

Sara Michaeli
Tel-Aviv-Yafo, Israel
2002