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-----Anodizing after Overmolding -- Tank Contamination from Plastic
Q. Hi there, I work at a company where we anodize parts and then send them to our plastics department to get overmolded. I have an idea of having our parts overmolded first and then anodized. Specifically our plastic is Nylatron with siloxane additive, is there any unforeseen issues that could arise from this? I've already sent a small batch of parts through like this and it worked fine but I'm not sure if it will scale up in regards to contaminates in our waste water/ affect microplastics will have on our anodizing tank chemistry.
Drew FloresFinishing lead - Bozeman Montana
December 10, 2025
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A. Hi Drew.
Although it's obviously never ideal to present extra opportunities for contamination of the process tanks, I think it's not likely to be a problem.
Still, this should be a common enough situation that other anodizers have probably tried it and hopefully we'll hear some actual experience as well as theory 🙂
Luck & Regards,
Ted Mooney, P.E. RET
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finishing.com - Pine Beach, New Jersey
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