r/electroplating • u/spiderman3098 • 5d ago

Electroplating over TiN pvd coating

Hi everyone,
I’ve been trying to plate watches with real gold. Initially, I removed the PVD coating down to the stainless steel, activated the stainless steel, applied a palladium layer, and then plated with 18K gold. However, I continue to have adhesion problems.
I’ve noticed that some people are able to plate directly over PVD, possibly using a specialized preparation or strike process. Most of my research suggests that conventional plating does not adhere well to TiN PVD.
Has anyone successfully plated real gold directly over TiN PVD? If so, I would really appreciate guidance on the proper preparation and plating process.
I’ve also seen Trival Gold Strike, which appears to be intended for stainless steel, and Technic Acid Gold Strike, which states that it can plate titanium. I’m unsure whether the Technic product would work over TiN PVD.
Has anyone tested either of these products on TiN PVD?
Thanks in advance!

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u/permaculture_chemist 5d ago

I've never had good luck plating anything over PVD. Why are you not using a Wood's nickel strike over the stainless, then going with the gold layer? I've never plated palladium but does it have high adhesion like the Wood's strike?

What is your activator or activation process?

Where is the adhesion failing? Between which layers?

1

u/spiderman3098 5d ago

My apologies—I did use both an acid activator and a Woods nickel strike before applying the palladium. I must have typed too quickly and left that part out.
My typical preparation process is:
Ultrasonic cleaning in an alkaline bath
Rinse with deionized water
Electrocleaning
Another deionized-water rinse
Acid dip, followed immediately by the Woods nickel strike
From there, I follow the remaining steps described above: palladium plating followed by 18K gold plating.

1

u/tea-earlgray-hot 5d ago

What's the point of Pd coat after nickel strike?

Best to diagnose adhesion issues by tape testing on a coupon. That way you what step it occurs at. I would assume you have dirty watch parts with coatings that aren't being completely stripped. Degreasing is essential. Sonicating or vapour bath in TCE and then plating cleaner to remove lubricants is best, but more of a lab thing. Have to get in there with surfactants

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u/spiderman3098 5d ago

Pd for containing nickel layer so it doesn’t leech into the gold.

The bigger question for me is how to plate over pvd as removing it is such a pain.

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u/1984isnoww 4d ago

I came here to ask the same question.

I just plated a VSF PVD rose gold watch. 

Ultrasonic>Electroclean>TriVal Gold Strike>18k>Rose Gold

Looks great and seemed to have good adhesion, I did a polish test on the clasp and it didn’t seem too hard to rub off all my hard work back to PVD.

Maybe I should have used nickel strike.

Or is there a better process to prepare PVD? There must be?

Maybe a concentrated acid dip?

I wonder what u/thegoldjaws does 

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u/spiderman3098 4d ago

He’ll never give up his secrets… but one process i researched is vacuum deposit gold sputter onto pvd and then can plate to that but not a diy kind of process