The finishing.com Hotline: Serious Education ... plus the most fun you can have in metal finishing. Ted Mooney, Webmaster
Rotogravure maker has chrome plating / grinding troubles
I would like to know certain things regarding chrome finishing. I'm presently operating a Datwyler Finishstar I would like to know why does grinding stone tend to damage engraved cells even though the head press is minimal? How can I prevent such things from occurring? I would also like to know which is better to use grinding stone or polishing tape? How can I achieve constant roughness of RA.03-.05? Any ideas?
rotogravure cylinder making - Manila, Philippines
Grinding chrome must be done carefully; when you start the first cutting don't remove more than 2-4 µm per minute. The grinding stone shall be soft on hard material like chrome. Also scratch the grinding stone often. Because if the grinding stone contains chrome this will give the chrome deposit some fretting. After grinding operation you can lap the area with a diamond charged polish.
for 4th generation
Rotagravure: European & American Methods
January 27, 2010
I am facing certain problem of roughness and blocking of fine dots in rotogravure cylinder while printing and this was a very serious issue and because of that I am loosing customer.So, please suggest what are the parameter I have to maintain and how it can be done.
Presently we are maintaining roughness of 0.04-0.05 and chrome hardness is in between 850-880 hv and we are using band polish to create roughness and criss-cross with a 9 micron lapping film.
gravures - Noida, U.P., India
February 4, 2010
gravure cylinder maker - Evesham
Rotogravure and Flexographic Printing Presses
April 12, 2011
Q. Dear sir
We have a problem with plating chrome over copper in rotogravure cylinder. After the cylinder is going to press and after 1 ton or less the chrome is going weak and the doctor blade makes scratches on the cylinder surface
So what I can do for this?
rotogravure cylinder production - cairo, egypt
January 5, 2014
Q. What is the empirical relation between the current density and the cylinder rotation speed during the process of rotogravure chromium plating.Ahmed Awad
- Alex, Egypt
^- Privately contact this inquirer -^
February 4, 2014
A. Dear all,
The better value to determine roughness is the Rz and the Ra as a comparable value.
As a cylinder lifetime it is not helpful to talk about the weight of the printed substrate rather than the meters printed.
If the chrome wears out fast, then these questions should be answered by the cylinder manufacturer:
- Is my chrome solution within specification?
- Is my chrome deposition good enough?
- Are my cells prior to chrome plating clean?
- Where is my roughness?
- Are my engraved cells within specs?
As a printer following should be answered:
- How are my doctor blade settings?
- Do I have premature drying ink in the cells?
- Is the doctor blade oscillating?
- Which cylinder regarding to type of ink is being rejected?
- Which substrate is printed and what are the temperatures of substrate?
Etc., etc., etc.
- Chonburi, Thailand