How to educate the customers? (He doesn’t know it may be costing him more).

• Ask how cylinder is printing on press.
• Ask how is registration.
• Communicate with customer.
• Get data about cylinder history.
• Group meeting is good experience to discuss problems in the industry.
• Possibly have customers at this meeting to share experiences.
• Look at target areas – reduce variables to find problems before they happen.

cylinder wear

A. (Lannie) We would expect a million or better impressions before strip and rechrome.
Depends on the ink also. If you are engraving a lot of subtle tones, it will wear out
faster.
A. (Bill) If we have wear in the first 50,000 impressions, it usually is a press problem.
The majority of the time if it is a press condition, you will have it damage the cylinder
right away. 100,000 to 200,000 may indicate a cylinder problem.
A. (Bob) This problem has been going on since they first chrome plated a cylinder. It is
a frustrating problem and people don’t like to admit in front of a group that they have
problems. It is not just a prepress or press problem. Ink can be a big factor, also.
Q. Finish requirement: If a plant has multiple presses with different finish quality, are
they running the same RZ? This is one of the biggest problems I see in the field.
You can’t run the same RZ on different presses.
A. (Bill) RZ can change drastically from one plant to another. The product is the same,
but the presses print differently and carry the ink much differently. It is critical to
communicate that inter-plant. It is important to communicate as much information as
possible to eliminate that as a variable.

How Often Must I Do Analyses?

•As often as necessary
This means if you do an analysis and your result is outside the proper operating range, then you need to increase the frequency of analysis.
If your result is out of range you should have analyzed sooner
•Increase the frequency so that all corrections are made while still within operating range
•Better to do analysis and scheduled maintenance on an amp-hour basis instead of by the calendar
When Calculating to Make Adjustments
•First make sure that it’s necessary. Did you do the analysis correctly?
•Don’t round-off numbers until your final result.
•Check your math, it’s easier than trying to “fix” your bath because you’ve made an error in calculation.

•Eye should be level with the part of the burette that you plan to read
•Read the bottomof the meniscus
•Watch for the color change and make sure that it remainschanged
•Take at least 3 readings and average results

Analysis/Titration Depends on Consistency

•Color change may be different for different people.

It may be best to have only one person doing titrations.
•Test under the same lighting conditions.
•If a result is out of range, retest beforemaking any changes.
•Document everything!

Additive

IT’S A SECRET!!!
It refines the crystal structure, providing uniform fine grains.
Fine crystal structure is essential for good cell geometry.
It provides copper of a controlled brittleness.
The crystals must separate cleanly without being displaced.

Current Density

If the current density is too low, the additive will not co-deposit effectively.
If the current density is too high, too much additive and/or other impurities will co-deposit.
If there is not enough copper at the cylinder, it will continue to plate; ANYTHING!!!

temperature of the electrolyte

The temperature of the electrolyte has an effect on conductivity.
Low temperatures make the bath less conductive.
Temperature also has an impact on the carrying capacity of the solution.
More material can be dissolved in the bath at high temperature than can be at low temperature.
Temperature can change the additive;
high temperatures can cause a breakdown of the organic compounds in the additive.
If you change the compound, you change its effect.

ANODE TO CATHODE DISTANCE

This is the distance from copper nuggets to the cylinder.Is it important?ABSOLUTELY!
REMEMBER: your bath conducts electricity
As the length of the conductive material (your bath) increases, so does the resistance.
The resistance increases with the square of the distance

Sulfuric Acid

The Sulfuric Acid makes the bath electrically conductive
Higher concentrations increase the conductivity
Lower concentrations decrease the conductivity
Increases or decreases in conductivity will change the voltage required to maintain a specific current density

CuSO4 What does it do and why is the concentration important?

The copper sulfate dissociated in the bath is the source of the copper ions (Cu++) for plating
Too low a concentration and there’s not enough copper ions getting to the cylinder, this can allow co-deposition of impurities
Too high a concentration and the copper ions inhibit the co-deposition of the additive

Why is Process Control Why is Process Control Necessary

•Keeping everything under control makes your job easier.
•Controlling the process makes it more consistent.
•Consistent products with no make-overscost less to produce.
•Low production costs add to job security by making your company more competitive.

Know your goals!

•First I want to produce a consistent product (after I achieve consistency I can then work on improving it)
•To produce a consistent product, my process must be consistent. Any variation in my process willproduce varied results.
•Maintaining my process to remove variation is therefore essential.
•Knowing about variations is the first step in controlling them.
•Testing lets us identify changes.
•Testing must be consistent.
•DOCUMENT EVERYTHING!

Controlling Your Process

•Regular analysis of the bath
•Fix it before it breaks (like changing the oil in your car)
•Set up maintenance schedules based on amp-hours of use
•Keep the area very clean
•Watch for any changes

Voltage At Working

 6 Volts at working current. Higher Voltage will increase temperature of your electrolyte and, if chilling system at your company doesn't work properly, will negatively affect your hardening additive and therefore the microcrystaline structure of the deposited copper.

Process Control

Solving Problems Correctly Is Important


Not Having Problems Is Better

“Right!…So How Do I Do That?”

Process Control

GOAL OF CYLINDER MAKING

• Correctly engraved cylinders going to the press....WITH NO REMAKES!

–Engravable copper is essential

• Fine consistent grain structure for uniform cell geometry

• Cohesive deposit that won’t displace copper or allow collapsed cell walls

• Ductility that allows for acceptable diamond life


HOW DOES THAT HAPPEN?

Following Directions is Good

CuSO4(Copper Sulfate) concentration 210-230 g/l
H2SO4(Sulfuric Acid) concentration 55-65 g/l
Temperature 28°-32°C
Current Density 20-35 amps/dm2

HOW MANY DO WE HAVE TO REMAKE?!

It  stopped Working !!

•Now what can I do?
•Set up procedures to deal with problem solving (this is good to do before you have problems!)
•Then FOLLOW THEM



We dont have Enough Time
If you don’t have the time to do it right, now………
When will you have the time to do it over?

•Use a Troubleshooting Guide

Whew !!

•What that all means is “Look before you leap”.
•Study the situation
•Collect information
•Look it over
•Make an educated guess
•Test that and only that

What Can Go Wrong?
If we take a quick look at the statistical possibilities of things that can go wrong,
we don’t even want to think about
“Murphy’s Law”

Scientific Method

Begins with the gathering of data by the observation of phenomena. By inductive reasoning a hypothesis or preliminary generalization is drawn from the data. The validity of deductions that follow logically from a generalization is tested by further observations and experiments. A verified generalization is considered a scientific theory; if contradictory facts arise, the theory may be modified to include the new facts or it may be replaced by a new concept. The scientific method is an expression of the scientific which rests on rational impartiality and on strict regard for accuracy and controlled experiment.

Getting Copper Onto a Cylinder is Easy

•Plating engravable copper is more difficult
•Additives are necessary•High current density is required to codepositthe additives
•High current density will also cause; burning, nodules, holes, etc.

What's a Plater To Do?

First Remember It’s Controllable
•This is electrochemistry, science not an art
•The process is governed by..Faraday’s Laws of Electrolysis

for more about faraday's laws see this link

 http://rotogravurecylinder.blogspot.com/2011/04/gravure-cylinder-basics.html

catch

•You Can’t Plate Engravable Cylinders if you have impurities in your bath
•An essential component of your bath is an impurity….the additive
•You Have a System Designed to Codeposit Impurities

Achieving Engravable Copper

•Proprietary Additives are used
•Part of the additive refines the grain structure
•Part is responsible for “Bonding” the crystals
•Using additives presents new problems

What About Hardness??

•Hardness has been a standard means of measuring engravability
•When grain size is reduced, the length of slip-planes is shortened, this results in harder copper
•When the crystals are bonded with “Additive”, the copper becomes harder
•Impurities that distort slip-planes will also harden the copper

Some of the Problems With Hardness

•Impurities can distort slip planes (the copper will be harder)
•Atoms of different metals have different sizes
•Controlling impurities is essential

Cutting an Even Cell Is Only the First Part

•Fine grain structure will produce a uniform cell, but it can still collapse or smear
•Maintaining that even cell wall is essential
•It’s necessary to bond the discreet crystals
•The “Hardness” additive forms sulfide spheres that array themselves between crystals
 •Slippage is reduced
•But the crystals will separate easily

The Copper Crystal

•A “face-centered” cube with an atom at each corner and an atom at the center of each face.

Crystals Can Grow to Large Size
•Atoms are added to the basic lattice
•Straight lines within the crystal are called slip-planes
•Viewed from the side the pattern is very regular

•Large crystals have long slip-planes
Distortion can occur along the slip-planes.
The copper would be softer if tested
If slip-planes are shorter, there’s less distortion. The copper would test harder

The Need for Engravabilityis the Reason for the Additive

•We talk about “Hardness” but
•Engravabilityis more than that……
•Grain Structure
•Ductility
•Cohesiveness

When you have large crystals……..
What you want……..……..may be different than what you get!

With smaller crystals……....
What you want…..…..…….is closer to what you get

Without “additive”, copper can be displaced as well as cut ............This copper can be pushed back into the cell

High Current Density Plating

•High current density is needed for co-deposition of the additive, in effect co-depositing an impurity.
•If the system is speeded up to co-deposit controlled impurities then it can deposit others.
•Doing anythingat high speed means that more attention is required.
 •Driving a garden tractor is similar to driving a car but slower
•Driving a car at high speed requires a lot more attention….. put the cell phone away

Plating cylinders for electronic engraving

•Plating cylinders for electronic engraving adds a different dimension to the process
•To produce engravable cylinders, additives must be used
•The use of additives requires higher than “normal” current densities
•Most cylinder plating is done in the range of 20-35 amps/dm2

Basic Electrochemistry and Process Control for plating gravure cylinder

Acid Copper Electroplating
•The Sulfuric Acid, Copper Sulfate (H2SO4, CuSO4) plating bath is very efficient.
•It’s very easy to operate and maintain under most conditions
•A primary condition is the recommended current density of 3-6 amps/dm2 (this not for engraving this density just for plating)

A Quick Review of the Process
•The Anode is the positiveelectrode, it also replenishes the bath with metallic ions
•The Cathode is the negativeelectrode, at the cathode metallic ions are plated out of the bath
•The acid component of the bath provides conductivity
•The metallic salt is dissociated and is the source of metallic ions for the cathode

to be continued....

UPS Systems With Engraving Machines

Bill Gray, Quebecor Richmond, spoke on behalf of the Exide Power Generating Systems. His
company was experiencing problems with power outages, surges and spikes. They lost over
130 cylinders due to those problems. They decided to purchase a 160 KVA Exide system. In
fourteen month’s they have had no cylinder losses. Since then, they have added presses to
the unit.
The Exide Rep spoke in detail about the systems available and stressed the importance of
having a self supporting power system. He indicated that his company offered a variety of
systems.

Question – Can you give us an estimate on what a three-phase system would cost per KVA?
In addition, are the bigger units more cost efficient than the smaller ones?
Answer – Bill said, from the rotary system that we installed, was four times less. A 160 KVA
system would be less than $20,000.

Sand Paper and Stone Polishing

Panel consists of Doug Bowers, Mark Herrald, Bob Smith and Wally Clevenger.
Mark presented a slide show on micro finishing, He has the micro-finishing head installed in
his plant in Des Moines. He commented, there are some advantages to this process such as
the roller oscillates and the paper is indexed, always providing a fresh surface for polishing.
For copper polishing, we are using a 15- micron lapping film and a 9-micron micro-finishing
paper.
A lubricant is used to keep the paper from building up. Estimated cost is approximately $1.83
for an 84-inch cylinder. The head can be retrofitted to most any existing polishing machine.
Heads with wider paper can reduce polishing time significantly.
Question –How much material do you remove and do you have trouble at the ends of the
cylinders?
Answer – First we were concerned about the dog bone on the ends of the cylinder. We go
back and forth extra times on each end to remove the buildup of copper and then we continue
to polish the rest of the cylinder. The first pass we get rid of nodules the second we
achieve the finish.
Question –Are polishing scratches smaller or larger than with stone polishing?
Answer – About the same.

Question –What is the cylinder roughness?
Answer – .05 to .06 RA and .25 to .30 RZ. Variance from end to end was .02 RZ.
Question – Did you find that with the micro finishing paper film you have less streaking on
press?
Answer – We do not have scumming or toning. It appears that we have less streaking too.
Question –Do you have to change the 15 and 9 micron paper between polishers?
Answer – Yes, you would have to have two heads which would polish at the same time to
keep from having to change papers. This would reduce the time by 60 percen

Diamond Engraving Tools

Panel consisted of Hugh McAllister, Mike Hunter and Edwin from Chardon Tools.
Diamonds are used for engraving because they are the hardest materials on the planet.
However, they need to be set up properly. A diamond can be weak and break.
A slide show was presented with examples of different diamonds and their characteristics. A
tool management program has been put into place to monitor tools in the process. To help
correlate problems with copper and how that relates to diamond tools.
Question – Is there a way to tell if the Styli is close to the end of its life?
Answer – One suggestion is to measure the last row of cells every fifty hours and visually
monitor the cell. Some customers get 800 hours on a tool, another with similar work may only
get 200. It is suggested to form your own individual method.
Question – What has the better life? Man made or natural diamonds?
Answer – It is hard to say that one gets better than the other does. It depends on material
you are cutting and other factors.
Question – What are the average running hours on a natural diamond?
Answer – 250 hours. However, depending on individual circumstances the hours may vary.

 

Cylinder Finishing Machine

Bob Speiss, K-Walter, gave a talk on the CFM (Cylinder Finishing Machine). This is a one step
process machine. It cuts the sides, face, and radius in one step. The next generation CFM3
will also eliminate de-chroming, as it will cut off chrome.
Panel Discussion – Joe Mezenski, Quad, Bill Gray, Quebecor, Bob Hopp, Quebecor, Paul
Gaddy, Southern Graphics.
Comments by the panel, CFM is about twice as fast as other machines and produces a nice
radius. Some of the first installations experienced some minor problems with the collar system
but K-Walter helped with these problems. The machine is fully programmable meaning numerous
cylinder sizes may be customized individually.
Quebecor, Richmond, was a beta site for the CFM and after some problems early on, they are
satisfied with the results of the machine. They are cuffing strictly chrome. For a one hundred
and thirty-one by forty-nine-inch circumference cylinder was obtained. By adjusting pressures
on the stone smoother, RZ’s were obtained. They were continuing to make minor modifications
to enhance the performance of the machine.
The packaging group uses 2,000 and 3,000 stones to produce a smoother finish. They also
are cutting to steel and following up with a 600 grit stone.
Bill Gray said they had experienced a problem with peeling. They determined that this was a
process problem and started to reverse polarity before copper plating. This allowed the newly
plated copper to adhere better to the base.
Question – What factors drove you to choose the CFM?
Answer – Bill Gray said, they were installing a new line and they wanted to automate and
have a quick turnaround, which the CFM provided. Other panel members commented that
automation and a quick turnaround were a high priority and the CFM worked well with a solid
base or a minimum plate process.
Question – Has anyone done any cost comparisons on the Polishmasters verses the CFM?
Answer – The tools are cheaper but, there are some consumables such as stones etc., which
are not used on the Polishmaster. On the other hand, if you use the machine to cut chrome
you do not have to purchase de-chrome solution.
Question – Would you expand some more on cutting steel?
Answer – An additive must be put in the water for cooling. Speeds should be adjusted and
specific and tools are used for steel.

Laser Engraving Update

Walter Siegenthaler, Daetwyler, gave an update on the laser engraving process. Laser
engraver has no mechanical moving parts. It operates off a light beam, which will engrave
approximately 35,000 cells per second verses a conventional engraver, which engraves 4,000
per second. The cells are round with flat bottoms with a similar look to an etched cell.
Different cell shapes are possible.
We are testing some alternatives for de-plating. Currently we are de-plating chrome and zinc
down to the copper base. We do no longer have to polish, we simply go into a standard degreaser.
We have increased the efficiency by using a 1 00 percent immersion. Only adding a
special exhaust to remove the zinc fumes we can use a standard polishmaster.
Before chroming, we clean with a paste. We are not totally happy with that and are working to
improve that process. The chrome itself-we was unable to achieve the results with cold
chrome that we desired so we have now switched to conventional hot chrome. There are
some modifications to the process we have to make for this to happen. Chrome polishing
remains unchanged.
Laser Engraving update We currently have three installations. The first is in Belgium, a packaging
printer. To date they have produced over I 0,000 cylinders with laser. They went straight
from a etching process to laser. They were using cold chrome with acceptable results. We did
change them over in late September to hot chrome. The second installation is MDC, which is
a publication printer. They were the first to have the hot chrome installed. We are testing a
dual head system
for them which should produce a 140,000 cells per second. The third installation is at Keating
Gravure. We experienced problems with the cold chrome there so we have switched to hot
chrome.
Question – You cannot repair the zinc-plated cylinder because when you de- chrome the zinc
comes off. Are there any plans to find a way to fix this problem?
Answer – Yes, we are looking into ways to be able to de-chrome cylinders.
Question – At the installation in Belgium, are they still doing some chemical etch?
Answer – They are still using some chemical etching.
Question – Is it possible to chemical etch zinc?
Answer – Walter – He’s unsure and has no intentions of going in that direction.
Question – Do you have any way of measuring cells, mainly in depth?
Answer – Walter – Of course you can measure the depth but the way we do the test cut we
don’t measure the depth. We need to be able to measure the power it needs to melt the surface.
Once we know that, we adjust the power accordingly.
Question – Can you engrave the zinc?
Answer – Walter says, we are testing now and the results look pretty nice. The hardness can
vary in the zinc by 20 to 30 Vickers with no problems.

Laser Engraving Update (cont.)
Question – How many cylinders have been engraved on the laser engravers?
Answer – Walter said, I 0,000 plus.
Question – What effect does hardness have on the durability of the cylinder?
Answer – Hardness is about 140 to 150 Vickers. The hardness is not the durability of the
cylinder.
Eliminating the Proof Press
Gary Wiff – Here, we have two of the publication people. I would appreciate it if you would
come up. Bob Hopp from Quebecor and Mark Herraid from RR Donnelley. I would like to talk
to you a little bit about the elimination of the proof press. Why do we proof? Sometimes we
have customer contracts that require it. Certain ob mixes require the proof press. We look at
the quality assurance. It’s a process check to make sure everything to that point has been
done properly. Sometimes prints are used to make color corrections. Sometimes we get different
paper styles that could influence the way a proof is marked up. We want to make sure
we have cylinders that will run in the process (runnability). We want to eliminate the lays and
get the ink formulations that we want to work with. Check the ribbon imbalance. Sometimes
Helio tends to have a ribbon imbalance in the process. Make sure we have the proper color
and proper text. One of the main things we want to do is to eliminate the press down time. A
proof readers job is affected down the line. This will give them something to do. Its time consuming
and job deadlines are getting shorter and shorter. Speed differences from most of the
proof presses run a lot slower. These presses don’t have the capability the production presses
have at running higher speed. Sometimes there is a difference in humidity and temperature
throughout the year from one area of the room to the proof press. Many times, we put on corrections
that have to be taken off the production press. I think that is a problem. The setup
can be hectic to change if only you have only one proof press.
A question is are you proofing in copper or chrome? Which way do you go? If you do proof in
copper, sometimes you end up with cylinder damage. Sometimes different cylinder circumferences
can be a challenge. Light conditions make a difference depending where you look at
the proofs. There is a lot of paper and ink waste associated with proofing. What happens is it
ends up blowing up with you because it cannot match the press?
Some of the steps of eliminating the proof press are that we can use standard inks. We have
done that in RR Donnelley by setting up the Bureau of Standard Specifications. We try to
setup and recommend ink varnish ratios that we can all work with. We have a standard digital
proof that we have adopted from our Kodak approval. I think it is a big step in involving the
customer. We want to make sure they understand what we are doing. There is a learning
cycle. We want to get everyone educated in the process.
We recommend using SPC (Statistical Process Control) to implement process checks. Driving
corrections back to Graphics is a big step. Instead of doing corrections on the cylinder now
we do them back in Photo Prep. That allows us to gain confidence in the process. L*a*b* factors
are instant checks.

Gravure Cylinder Basics

The Universe is Governed

by Natural Laws
Gravity
Motion
Mass
Energy
Etc.

Your plating process is governed by
Faraday’s Laws of Electrolysis

1. The amount of chemical change produced by an electric current is proportional to the quantity of electricity that passes.

2. The amounts of different substances liberated by a given quantity of electricity are
proportional to their chemical equivalent weights.

Faraday’s Laws can be expressed as a formula

g = I e t /96,500

Current in Amperes
Chemical Equivalent
Weight Time in Seconds
Faraday’s Constant (coulombs)
Weight in Grams
g = (I e t/96,500)?

How can this be important

The entire electroplating process is governed by these laws Any problem solving must keep Faraday’s Laws as reference This carries through to all plated results If the engraving  characteristics are other than predicted it can be explained through Faraday’s Laws. If the thickness is other than predicted it can be explained through Faraday’s Laws.

In order to co-deposit additive, the deposition of copper must be limited.This is done through:

1. regulating the current density
2. controlling the concentration of copper ions
3. controlling the acid concentration
4. controlling the concentration of additive Not enough copper?
Either something other than copper is depositing. § Hydrogen § Garbage Or you’re missing something in your calculation. What can you do if your cylinder plating goes BAD? Go Back to Basics! Sulfuric Acid concentration Copper Sulfate concentration Current Density Anode to Cathode Distance Temperature Additive Dosing Filters Cleaners Sulfuric Acid Sulfuric Acid provides the conductivity to the bath.

Controlling the current controls the plating deposition at the cathode.The amounts of anything  plated vary according to Faraday’s Laws of Electrolysis. Controlling the current controls the deposition of copper and additive. Copper Sulfate Copper Sulfate (CuSO4) is dissociated in the bath as Cu++ [SO4]=.The concentration of the Copper Sulfate is in fact the concentration of Copper ions available to the cathode. Copper will tend to plate preferentially. Too high a concentration and deposition of the additive is blocked. Too low a concentration and too much
additive can be co-deposited. Current Density Current Density is a measure of total current
and the area to which it’s applied. The current determines the rate of deposition. Low current density…. Slow deposition. High current density…. Fast deposition. Higher current enables the deposition of additive.Too high…. Too much additive.Too Low…. Not enough additive.Anode to Cathode Distance

Resistance of the bath varies with the square of the distance.

The distance is also critical to even deposition Too close can cause banding, too far and
the voltage requirement is too high. Temperature Temperature also has multiple affects.
Higher temperature decreases resistance in the bath. Temperature affects solubility, low
temperature can cause precipitation or crystallization of bath components. The additive is an organic compound that can be damaged by high temperature. Additive Dosing The  concentration of the additive in the bath will affect the amount of additive codeposited.
If the bath is over-dosed with additive it will cause problems with brittleness also
additive that remains in the bath will breakdown and lead to organic contamination.
Filters It’s important to remember that the function of the filters is to keep the bath clean.
Elevated current density forces the codeposition of things other than copper.
A dirty bath has lots of things in it that can get on the cylinder and be the cause of
problems. Cleaners Cleaners are used to clean. If the cleaner becomes dirty and tired then
instead of cleaning it dirties.

Attention to the Basics Is Attention to the Process