Where the
world gathers for metal finishing
Q&As since 1989


-----

Improper "cell geometry" in acid copper plated gravure cylinders

Hello,

I am vijay, managing a plating shop in Gujarat , India , manufacturing copper plated gravure cylinders for engraving. Off late, I received few OBSERVATIONS from our engravers pertaining to bad cell structure/GEOMETRY while during engraving on our copper plated cylinders.
Can anyone please answer as to what could be the possible reasons for improper cell geometry during engraving, in spite of having hardness in the range of 200 - 220H, is it due to contamination in the plating chemistry or is an engraving related issue.

Apart from ductility and hardness, what are the other factors that determines the formation of a good quality cell geometry in engraving?

Response to my query would help in resolving any ambiguity regarding this issue and help to overcome the same.

VIJAY KUMAR
MANAGER PLATING SHOP - GANDHINAGAR, GUJARAT, INDIA
January 18, 2011

---

google copper plating grain size.
Check your library or college library for good plating books.

James Watts
- Navarre, Florida
January 19, 2011

---

January 21, 2011

Hi there,

did you check your ductility by doing a ballard skin? Other influences which can lead to bad cell shape and reduced stylus life time can occur from high iron/nickel/hexchrome contamination. Also organic contamination could lead to these kind of problems. What's your DI-Water quality? Is it a chloride-free or chloride containing process, additives then can vary.

Best Regards,
Dominik

Dominik Michalek
- Melbourne, Australia

---

Hi Dominik,

Thanks for your reply, but from the feedbacks of our engravers, they are getting a good stylus life and no incidents of stylus break/chip while engraving on our cylinders, and most of the time they do get good cells during engraving.
Now coming onto your point regarding quality of DI water,we use only chloride free water and also our process contains no chloride, also, the basic issue of improper cell structure is not a common one but encountered occasionally and no two cylinders from the same tank has this issue, which is the most intriguing part of the whole issue.

Pls, do not treat this as a question, but would rather like this to be a discussion, wherein individuals who might have faced similar issues can pitch in with their observations.

Thanks.

VIJAY Kumar
- GANDHINAGAR, GUJARAT, INDIA
January 30, 2011

---

February 2, 2011

Hi,

which hardness do you have and did you carry out a ductility test? Is the shoe and the burr cutter on right position? Possible for you posting pictures here to have a closer look on this issue? Does the cell deformation occur all over the cylinder,....or does it vary between engraving start and engraving end? It is also important to know with which stylus angle, size and screen does it occur.

Thanks and receive the best wishes.

Dominik

Domink Michalek
- Melbourne, Australia