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Flash Gold Plating (50 Microns)

Hallo Sir,

I have been told that with flash gold plating solution there is a way to get 30-50 microns of gold onto jewelry Person who have told me he have looked in a history of plating book, he found that if you put about 5 times the normal amount of gold into your bath,lower the voltage and increase plating time, you can plate that thickness in an hour or so and have it come out bright. This will give a very thick and durable coating of gold. Is it possible or not please advise me?

I wanted to plate 30 to 50 microns of gold in watch. Note:I'm not talking about 30 to 50 microinchs.

Thank you,

Dipen Pattni
jeweler/goldsmith - Dar-Es-Salaam, Tanzania
2002

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First of two simultaneous responses --

Hello, Mr. Pattni. 30-50 microns is very thick, whereas the word "flash" usually means exceptionally thin. But layers much thicker than that are routinely plated to make electroformed hollow gold jewelry. If you are using your own "home brew" gold plating solution, it is hard for us to know whether it will work. Is it a cyanide flash, or a bright acid gold, or what?

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002

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Second of two simultaneous responses --

I have seen gold plated over 1/2 inch thick but we sure did not call it "flash". The term flash is not used in the USA for heavy deposits - flash usually means about 0.000 010 inches thick or 1/4 micron.

Several vendors have processes that will lay down 50 microns.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2002

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2002

Dear Ted,

I don't know the type of bath, but I'm buying solution from my supplier and I'm adding 68% GPC in the instagold flash bath 2grams per gallon.

My supplier is telling me you can plate but you have to add brightener and 1 oz of GPC per gallon and you will need lot of agitation then I can plate very thick.

I want to plate 50 micron on watch, base metal is brass and SS. Please advise me is it possible or not, or I need different they of bath?

Thanks,

Dipen Pattni
jeweler/goldsmith - Dar-Es-Salaam, Tanzania

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I'm not a hands-on gold plater, Dipen -- just a guy who reads and listens and watches. A cyanide strike bath is usually not considered the best basis for a high-speed gold plating bath, but I think your supplier is advising you correctly and that you can plate a heavy thickness by increasing the gold concentration, using agitation, and employing a proper brightener.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002

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Dear Ted,

:) I know you reads and listens and watches. I'm sure that my bath is not a cyanide strike bath. Anyway I'll spend 1 oz of GPC and brightener let see what happen ;(

My supplier is Gold Touch [a finishing.com supporting advertiser] they have advised me lot but they have never done heavy thickness like I want. So I think let me post the question in finishing.com, masters like Mr.Ted or others can help me. My english is not good please try to understand.

Thanks,

Dipen Pattni
jeweler/goldsmith - Dar-Es-Salaam, Tanzania
2002

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2002

It's not clear to me if you are running alkaline cyanide gold or acid gold cyanide. What is the pH? According to Weisberg's great article in the Metal Finishing Guidebook, you should have 4-8 g/L of gold for heavy deposits. This is much much higher than you previously had. He notes the use of either cobalt or nickel for alloying, agitation required, a current density of 10-20 A/ft2, and temperatures between 80 and 100 °F.

 
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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Dear Mr. Ted,

Solution powder itself does not contain the cyanide, type of bath is acid gold bath that is both electrolytic and immersion, pH is 4.4 to 4.8.

Thanks,

Dipen Pattni
jeweler/goldsmith - Dar-Es-Salaam, Tanzania
2002