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How to plate a two-shot ABS molded part

2001

I want to do a two shot decorative ABS molding and then electroplate one of the shots. I mold the plateable part first, then the non-plateable part. The only way I can attach an electrode to the plateable portion is by running a boss through the back of the part, ie, through the non-plated shot.

Am I to understand that this will result in the platable part not being plated? Because the initial copper layer can't form a continuous circuit from the electrode to the plateable areas? ( It's broken by the non-plateable part)

If so, is it possible to add something to the plateable ABS to make it conductive? Like carbon or metal particles? Does anyone sell this material?

George Patrick Gorman
- Melbourne, Victoria, Australia

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2001

George,

I am not a plater and know (nearly) zilch about plating but a little about plastics.

ABS! Well, I dunno what grade of ABS you are talking about, maybe it's pure BUT the ABS pipe material is black and contains, ah, 3% to 5% of carbon to give it UV stability. Many common plastics are colored for improved UV stability.

Hence any moulder worth his salt could easily add carbon to the ABS ... but what that would do to the plating potential, I dinna ken.

ABS has another peculiarity ... it cements SUPERBLY ! In fact you can edge cement ABS pipe to form a perfect and strong joint (if you know what you are doing, that is!). The idea here is that maybe you could consider a cemented 'conductive' area. Get some ABS solvent, MEK / methyl ethyl ketone, and make up your own heavy, 20% or so, cement ... give it a try, anyhow.

CHEERS,

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

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Well, there is a special way to mold the conductive and non conductive ABS and there is a special process to plate it. The point is that although it is a conductive plastic you cannot attach an electrode to it and plate it as if it was a metal. There is a special process that makes it work. You will have to turn to suppliers for this process.

Sara Michaeli
Tel-Aviv-Yafo, Israel
2001

George,

You are going to have to add a lot of carbon or metal filler to the ABS to make it conductive, the big problem being the individual particles are surrounded by non conductive ABS effectively insulating them from each other. Also the amount you would need to add would change the physical properties of the ABS.

Have you thought about insert moulding ?. Mould and electroplate the first component then use it as an insert and mould the second component around it.

Tim Strickland
- Auckland, New Zealand
2001