Re: Problem with E-coating over Zinc Non-Chromate Plating [ Started by barbkopko in General Discussion : 3 replies ]

Automotive industry uses a phospate layer to improve adhesion.

Re: problems with adhesion [ Started by sk8 in Forum Announcements : 6 replies ]

What type of bath are you using?

Re: NICKEL BUILD UP [ Started by Daniel in Electroplating : 2 replies ]

Thanks !

Topic: problem on small anode area [ Started by Daniel in Electroplating : 1 replies ]

What are the problems related to small anode area ?

For example nickel solution is depleted more fast and the coating is brittle because the oxide formed?

where this oxide come from?

Thanks



Re: Blisters on electrocleaning [ Started by Daniel in Electroplating : 3 replies ]

thanks, sorry for the delay



Re: Copper plated pillars are looking dome shaped instead flat [ Started by sathish.y in Electroplating : 3 replies ]

A picture could be useful


Re: Mild Steel with Zinc Chromate & black Passivated [ Started by ivanteo in General Discussion : 1 replies ]


Zinc chromate is a chemical conversion coating applied over zinc

Ranging fron clear(blue) , yellow , green and black

in that order is the protective value

Black passivated could be the black oxide coating wich is not so good in terms of protective value

for example firearms are mostly coaated this way



Topic: NICKEL BUILD UP [ Started by Daniel in Electroplating : 2 replies ]

What are the problems related to nickel build up (metal content )on the solution  on a watts type bath?

Thanks

Re: Mirror polish stainless steel scratch and finger print protection?? [ Started by Almajoja in General Discussion : 4 replies ]

PVD is the solution

Topic: Nickel peels off [ Started by Daniel in Electroplating : 2 replies ]

I'm facing trouble with a copper part (phospor bronze)Nickel peels off after one day or two the treatment is nickel plate in watts bath, part made of sae65 copper alloy. It rusts in the same place on all the parts and when the nickel is removed you can see the bronze.

Need help!

Thanks

<img src="user-uploads/SFA/pieza (Large).JPG" />


pieza (Large).JPG

Topic: Blisters on electrocleaning [ Started by Daniel in Electroplating : 3 replies ]

Hi everybody!

I am plating high polished brass parts and when i electroclean them if i use too much time i see blisters during or after the plate (nickel watts)


does anybody know the reason (nochromium present en electroclener)

Re: Cast iron plating [ Started by Daniel in Electroplating : 2 replies ]

Yes Ultrasonic cleaner can work as the imploding bubbles can clean the part, but

in the case of the acid electrocleaner  how it work?

In the electrolitic alkaline cleaner the bubbles formed can clean the part without attacking the iron.

where is sand involved Fluoride must be used, fluoride removes silica from the sand used on casting.

Iin what other ways the flouride helps to clean the part?

I dont have an ultrasonic cleaner yet, but i can try a electrocleaner.


Thanks!!!

Topic: Cast iron plating [ Started by Daniel in Electroplating : 2 replies ]

When there is very rusted part and i use acid the part becomes covered with a dark smut, that dark areas dont allow the plating operation.

I imagine, that  is  due to the high content of carbon, and then when you apply acid the metal is removed and the carbon is exposed.

What i do is to try to avoid the use of acid, instead of that i use abrasive methods.

Sometimes is expensive.

Is there any other method ?

For example if the black smut appears is there any method to remove it?

Topic: Voltage on acid chloride zinc bath [ Started by Daniel in Electroplating : 1 replies ]

I have read an article that says that the voltage used on acid chloride zinc bath must not be over 8 beacuse anode baskets corrode

two questions

1 it is the same for nickel?

2 it does apply for barrel plating ?

Topic: Copper thickness [ Started by Daniel in Electroplating : 1 replies ]

Why does de the strike bath, rochelle and acid copper have different layer thickness?

Strike up to 2.5 microns

Rochelle up to 8 microns

Acid or High efficiency:  any


It is because beyond this thickness the coating is spongy?

Topic: Asking about copper strike bath [ Started by Daniel in Electroplating : 3 replies ]

Im dealing with a copper strike bath, i dont know the exact composition, i believe thet is not a rochelle type it is a plain cyanide type one.

I am surprised how difficult is to control the bath without a chemical analisis.  because the can be done each month, and the bath became unstable between thet period of time.

We proccess zamak parts, it is a zinc alloy, and the parts sometimes become qith a brassy appereance.

how can i know the reason of why is the bath attacking the zinc?

Maybe pH too high, if that is the reason how i can lower this value?

Maybe free cyanide too high?


it is best to change to a rochelle cyanide

 …

Re: Zinc Plating bath control ? [ Started by asad.ilyas in Zinc Plating : 5 replies ]

Cyanide zinc baths are among those with less control, they can operate with huge amounts of grease and if they are contaminated with copper  the deposits are not white, they became yelowish some book reports operating to 60% of oil(i cant believe it) so usually the operators just add zinc oxide, brigthener and purifier. and remove the sludge from the bottom of the tank often.

Chemical analisys is left to the supplier, how is your bath do you use zinc anodes?, steel anodes?.

Re: Anode/Cathode Reversed Definitions in Plating [ Started by mark robison in Electroplating : 1 replies ]

By definition anode is the place where oxidation occurs.
Oxidation is not only the combination with oxygen, oxidation is the change of the valence of the atom.

If it is raised it is called oxidation is it is reduced it is called reduction, so calling the anode as the negative pole is ok for plating, because it is there where the oxidation occurs.

In the cathode the metal it is reduced, it pass from valence to zero from +1 +2 etc. and in the anode it pass from zero to +1 +2 etc.

Re: Nickel Chloride Too high [ Started by Daniel in Decorative Plating : 13 replies ]

The fluoboric acid did it well, no pits allowed to appear this time!!

But now i see small little etching maybe known as "StarDust"

Any ideas?

Thanks

Re: Nickel Common Ion Effect [ Started by DustinGebhardt in Electroplating : 1 replies ]

Common ions sulfate from nickel sulfate and sulfuric acid and nickel sulfate and nickel chloride?.

too much chloride or sulfate can create a less soluble salt? so the one of the nickel salts precipitate, for example nickel chloride?

i have never seen that......

Re: Trivalent chromium removal from hexavalent chromium bath [ Started by Daniel in Decorative Plating : 3 replies ]

Thanks!

is there a way to know when the treatment is done, for example cathodes not spongy at certain current density, anodes blue and shiny etc.?

Topic: Trivalent chromium removal from hexavalent chromium bath [ Started by Daniel in Decorative Plating : 3 replies ]

Actually i´m doing the old school  method to convert some trivalent chromium to hexavalent chromium.

Using small cathodes and large anode area to achive  high CD on cathodes low CD on anodes.

what is the correct appereance of the cathodes after the procces is done what is supposed to be seen on the cathodes ?

what is the correct amount of time or how many times i have to do this treatment if my bath is highly contaminated?


Thanks

yes i know i have to practice more with my cell phone about the pictures i take. sorry


Attachments:


Imagen0053.jpg
Imagen0055.jpg …

Re: Nickel Chloride Too high [ Started by Daniel in Decorative Plating : 13 replies ]

Thank you for all of the great advice!  I have not done the test yet but I'll let the forum know as soon as I have the results.

Re: Nickel Chloride Too high [ Started by Daniel in Decorative Plating : 13 replies ]

what about fluoboric acid, it is good? and what could be the correct amout of it for the acid dip?

Re: Nickel Chloride Too high [ Started by Daniel in Decorative Plating : 13 replies ]

Thanks for your time

i must run the samples next week and then i will contact the forum again.

But by the way , why and /or where the lead could come from

Could it be that they are using brass for machining that has Pb?