The authoritative public forum
  for Metal Finishing since 1989

Charcoal filtering Nickel Sulfamate?

-----
2006

I would like to know if its ok to use a charcoal water filter to filter my sulfamate bath?
If so, is there a particular one to use?
Can I just use this filter for regular filtering?

Ed Schuster
Hobby - Los Angeles, California

---

Yes you can mainly to remove organics from your solution ,but it will remove your anti-pit as well.

Khair Shishani
aircraft maintenance - Al Ain, UAE
2006

So I guess this should be done once in a while not every time. I am only plating silver painted fiberglass parts, what would happen without the anti pit agent, would it act the same as plating steel parts?

Ed Schuster
- LA, California
2006

---

Although there are certainly many different types of pits and other potential defects, the type of pits that "anti-pit" deters is 'gas pits' or 'hydrogen pits'. As the plating process proceeds, a certain amount of the electricity applied generates hydrogen bubbles on the surface of the part instead of depositing nickel. If the nickel deposits around the hydrogen bubble, you will be left with a small hemispherical depression. An "anti-pit" is a wetting agent that dislodges the bubbles.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

Charcoal filtering is good in reduction of impurities but it can also reduce some organic additives so that it is not advisable as continuous.

Teody Delgado
- Manila, Philippines
2006