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Gold flash vs. plate


Q. I'm wondering whether there are any standards regarding what thickness of gold constitutes "flash" and what constitutes "plating". In particular for the terminals/pins on connectors.

Thank you.

Bruce Jdeleted
cables - Santa Ana, California, USA


Those terms are meaningless.

jeffrey holmes Jeffrey Holmes, CEF
- Spartanburg, South Carolina


A. In the jewelry industry there are distinctions for "flash", gold plate and heavy gold electroplate.
"Flash" refers to thicknesses less than 7 millionths; gold plate, above 7 millionths; and heavy gold electroplate, 100 millionths of an inch. All measurements are expressed in terms of 24 karat gold.
In electronics plating these terms are not recognized.

John Carlotto
Innovative Coatings, LLC

E. Providence, Rhode Island


A. G'day, The term flash means to just cover the job with enough gold to give it a uniform color. Usually a cyanide gold. The term plating is short for electroplating... Connectors have varied uses. Some require more gold than others. Most mobile phone connectors have a thickness of 1.25 microns near the tip. Most connectors are electroplated in an acid hard gold first. This gold is an alloy and offers better mechanical wear protection. Then a flash of 24 kt cyanide gold to give it an even color.

Richard Bancroft
- Carrum, Vic, Australia


A. Flash gold plating is less than 0.25 Microns and usually not done on connectors. For this purpose, Cobalt or Nickel hardened additives are used in the Acid gold bath and usually a thickness of >1.0 Micron gold is deposited and is subjected to tests such as contact resistance, wear resistance, porosity etc.
In this case Mr. Bruce J has to set his requirement first.

T.K. Mohan
    plating process supplier 
Mumbai, India

December 20, 2012

A. Bruce:MIL-DTL-45204, Paragraph 6.3.1 defines a strike/flash as any plated material under 10 micro-inches or .000010. Depending on your application, we see 30 micro-inches of gold commonly on commercial connector applications. Mil-specs such as 39029 are 50 micro-inches min but also allow localized finishing. We routinely process size 16-22 gauge pc tail contacts and sockets with copper flash, nickel 50 min, gold flash/strike overall then selective plating mating end of socket or contact.

Foresight Finishing Casey Weizel
Foresight Finishing LLC

- Tempe, Arizona


Q. Is there a Standard that defines gold flash?
IPC J-STD-001D [link is to spec at TechStreet]3.9.3 calls for gold removal on parts with >2.5 microns of gold on through-hole components and terminals. Spec sheets don't give the gold thickness, some do refer to gold flash. We use HASL in our Class 3 process, so this is an issue.

IPC calls for gold removal from 95% of all surfaces of surface mount devices regardless of gold thickness.So we have to double tin.

Thanks in advance for any input received.

Carol Sdeleted
aerospace - Lindsay, Ontario, Canada

May 23, 2008

Q. Thanks for above explanations.
Then, can anyone teach me what is the difference between coating and plating (using on connectors)?

Golo Wu
- Taipei, Taiwan.

May , 2008

A. Hi, Golo. These are imprecise terms, and context dependent, and people don't always use them consistently -- so it is not a good idea to try to put too fine a point on it. A "plating" is often applied by electroplating whereas a "coating" does not imply what technology was used.


pic of Ted Mooney Teds signature
Ted Mooney, P.E. RET
Brick, New Jersey

December 13, 2012

Q. Can anybody tell me if the bath/machine used for micron plating is different than a flash plating bath? If so, could you tell me the difference?

Thank you in advance

Steve Fisher
- New Zealand
  ^- Privately contact this inquirer -^

December 14, 2012

A. Hi Steve. The problem is that these terms have no accepted meaning at all. How can we put a fine point on them? :-)

To many people, "micron plating" means gold plating to a thickness of approximately 1 micron thickness (i.e., 40 millionths of an inch) for high quality costume jewelry or gold plated sterling jewelry. I would consider this thickness to be greater than a flash plating, which would be more like 10 millionths of an inch -- just enough to give color. And I would use the term micron plating only to describe gold plating, not other plating.

But, yes, you can easily deposit either 10 millionths or 40 millionths from the same bath and same machine. Good luck.


pic of Ted Mooney Teds signature
Ted Mooney, P.E. RET
Brick, New Jersey

February 10, 2013 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. Good evening

I am Interested in a Chain of Stainless steel with VERY thick Gold Plating (more than 20 microns) that supports scratches without going all the gold of the Surface.

So I contacted a Jeweler's shop in China and they tell me that they can do with 50 Microns gold plating but it will be Expensive.

My questionis, is normal gold plating 2-3 microns but 50 is too much right for one Chain?

And do you think it's really possible to make that Thickness?


Martin Martinez
Student - Montevideo, Uruguay
  ^- Privately contact this inquirer -^

February 12, 2013

A. Hi Martin,

50 microns of gold is certainly possible, even thicker coatings can be obtained. The platers in China are correct though, that is going to be very expensive.

Thickness is dependent on what you want it to do, but a thick coating for jewellery chain is more like 5 microns rather than 20 microns.

Brian Terry
aerospace - Yeovil, Somerset, United Kingdom

March 9, 2013

A. Normally I am used to have open calculations when talking gold plating, but I would certainly check if 50 microns actually was applied.

Bo Konig
- Aalborg Denmark

March 11, 2013

A. I will agree with the other respondents and say 50 microns of gold is very possible. I once worked for a company that plated more than 127 microns of gold on electrical contacts. One thing I will tell you is that it will not be shiny gold when you are done. Also when plating those thicknesses of gold the bath has the strange and inexplicable ability to keep drawing current while the metal deposition stops completely. We never figured out how this was done. We just knew that every 5 microns or so (.0002") we would have to pull the rack and run it through an acid reactivation cycle and then continue plating. A real pain in the derriere.

Tim Hamlett, CEF
      Quality/Laboratory Supervisor -
Ft. Lauderdale, Florida
Tim Hamlett
Anodizing - Pompano Beach, Florida, USA

April 22, 2013

Q. Hi, what is the difference if I will use 30 microns of gold instead of 50 microns? Do you think any problem would occur? Anyone please answer.

Jayson Pamienta
- Naic, Cavite, Philippines
  ^- Privately contact this inquirer -^

April 25, 2013

A. Hi Jayson,

You really need to give us a lot more detail about what you are using the gold for, rather than asking an abstract question. All I can tell you at the moment is that your gold will be 20 microns thinner!

Brian Terry
aerospace - Yeovil, Somerset, United Kingdom

October 9, 2013

Q. Just a question for all talking about plating with gold --
If this process does not last long and is expensive, will you consider plating with titanium oxide using the ipg, or pvd coating process (vapor deposition system)?
Looks to me the same (gold color) and lasts longer and also you can do different thickness (for jewelry mainly).
I will appreciate any comments regarding this matter.
I do really need to know what people with more experience think.

Jorge Sepulveda
- Huntington Park, California, USA
  ^- Privately contact this inquirer -^

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