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Electroforming on resin substrates

I am trying to electroform nickel on a isopthalic resin with fibreglass substrate. The metallisation is done by reducing silver onto the surface. when the job is separated, I find that there are small bright bubbles formed on the silvered side of the electroform. The further layers form on those bubbles and the shell forms that way. The quality of the electroform is obviously a reject. These are not the conventional pitting bubbles that are visible on the other side. Is my reduction method faulty, or is there a better method available such as a spray kind of metallic paint. Is the resin substrate at fault, maybe some uncured resin parts coming out from the substrate. I am using the conventional sulphamate ( 350 gpl ) bath.

Nitin Kibe
- Pune, India
1999

You have pin holes in your master that are expanding in the hot nickel solution,you can spray paint to seal or copper plate a thin layer in an ambient sulphate bath.

Kenneth Ian Foyn
- Durban South Africa
2000

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