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Rinsing time before electroplating

adv.    

March 24, 2008

Dear Sir

We do ID hard chrome electroplating on cylinder sleeves. Before the process we do alba washing and then soft water rinsing & Etching.

How much time should be given to workpieces before the electroplating or after rinsing so that no rust appear on it?

Mohsin Siddiqui
- Karachi, Pakistan

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There should be no delay at all between any steps, Mohsin. The parts should be rinsed for the minimum time which allows good rinsing (probably something like 30 seconds, depending on the part and the amount of agitation available), and allowed to drain for the minimum time that does not cause excessive dragout and pollution. In no case should they be allowed to dry. Good luck. P.S.: I don't know the meaning of "alba". Thanks.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 25, 2008

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Dear Sir Ted

Alba-788 is a chemical that we are using for cleaning the workpiece (any impurity, oil etc) than workpiece go to rinsing tank and than to etching followed by hard chrome electroplating.

what is the probability of getting rust after rinsing, when we left the part for 10 mins after rinsing / before etching it gets rust so quickly, what could be the reasons for getting rust on workpiece?

please help

Mohsin Siddiqui
- Karachi, Pakistan
March 25, 2008

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The answer is: don't do that, Mohsin. It is improper processing to take a part out of the line after cleaning. Clean parts are susceptible to flash rusting; it is no surprise that they rust in 10 minutes.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 26, 2008

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Dear Sir Ted

Thank you for your answer, I was really worried about the case that why do the parts get rusted so quickly after cleaning.

Mohsin Siddiqui
- Karachi, Pakistan
April 8, 2008

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June 5, 2008

hello Mr. MOHSIN,

YOU FIRST MAKE READY YOUR HARD CHROME PLATING TANK,

THEN START FROM CLEANING PROCESS,ETCHING,RINSING,AND HARD CHROME .

NO STAY BETWEEN ANY STEP.

ENJOY PLATING,

BYE,

AFTAB

KARACHI

Aftab Jahangir
chemist - Karachi, Pakistan

They flash rust because they are clean, chemically active,wet and exposed to oxygen.

James Watts
- Navarre, Florida
June 7, 2008

adv.