The Offset Pressman

Ink is Only a Fraction of Offset Costs Ink is only a fraction of the actual cost of offset printing , but can be the root cause of a myriad of problems.  This makes troubleshooting offset printing ink a daunting task at times.  There are so many demands on ink to print good quality in a complicated process.  Let's examine how you can troubleshoot just a few problems with your offset printing ink . 1.  High Dot Gain Ink is not the only factor to consider in this case.  There are many other factors to consider relating to your plates, pressure settings and chemistry.  Let's just consider a couple possibilities that may involve the ink itself that is causing high dot gain . Cause:   Ink viscosity too low.  Solution:   Consult your ink manufacturer and request change.  Increasing your viscosity may make an improvement, but cause problems in other areas.  Ask your supplier for help to understand all the underlying issues. Cause: Improper ink and water balance.  Sol

  by Frank Drazan   Few Question It's Importance It is doubtful that you could find anyone who would not agree that preventative maintenance is a necessity.  Many will claim that you will die in terms of profitability if you don't do it.  It's like motherhood - everybody loves it.  But realistically, with the possible exception of lubrication, preventative maintenance is only a gleam in the manager's eye.  Rarely does anyone practice what they preach.  As a matter of fact, even breakdown or slowdown maintenance is rarely performed .  Patch-ups are the norm. Control and Administration Nothing we decide on here will change that.  It comes with the territory.  The real question is how much maintenance do you need and how do you control and administer it?  With regard to how much do you need, there is no answer.  Actually it's a lousy question.  The real question is, how much maintenance can you handle, and what type of equipment and manpower do you need

A flying paster follows a sequence of events that are timed in such a way as to allow an expiring roll to splice onto another roll that is travelling at exactly the same speed.  Below is a video showing how it works: flying pasters usually have two or three roll mounts they require precise timing to splice properly have other functions such as roll alignment and tension control are used on high speed web offset heatset presses Here are the steps a flying paster goes through to change an expiring roll: Flying Paster Arm 1.  A prepped roll is sped up by a belt or servo driven motor to the exact speed of the running paper.  This is usually accomplished by a laser reading a mark put on the prepared roll. 2.  The splicing arm comes down to a position that puts the running roll in very close proximity to the new running roll. 3.  A signal is given when the expiring roll is down to the minimum diameter. 4.  The splicing arm quickly presses the running roll against the new rol

When examining digital and offset printing , it is important to have an unbiased viewpoint. As someone who offers both services to customers in a high volume print shop, I would like to tell you the advantages and disadvantages of both. While many will tout that offset printing is vastly superior in quality, I can assure you that the latest digital printers make the difference virtually negligible. Unless you're corporate identity is critical to a specific pantone color, which many digital printers today now offer, digital printing comes very close to offset. So to simplify, this leaves two main criteria to evaluate both offset and digital printing - quantity and turnaround. Let's look at each process. Digital Printing This medium lends itself to shorter runs and quicker turn around for several reasons. Digital printing is not much different than clicking "print" on your home computer. It's easy to print off a few copies. It's quick and conven

Flying Paster A flying paster is a splicer for a web press that is used for continuous production.  It works by "pasting" an expiring roll onto the next so that the press does not have to stop.  The "flying" aspect of it indicates that it accelerates the roll to the same speed of the press and then quickly performs the splice. Almost all large presses have either a flying paster or a zero speed splicer.  Both accomplish the same task for the pressman: allowing the web press to continue running without stopping or slowing down.  Flying pasters are generally used on higher speeds presses. Most modern flying pasters are equipped with a roll stand, dancer roller, metering roller, splicer and web guide.  While some of these systems are used to operate as a separate part of the press, press manufacturers are integrating these into one unit.  Here is a breakdown of each component. 1.  Roll Stand This part of the flying paster cares for mounting and holding the r

Ink and water can and do mix to balance properly.  But why does it work?  Read on. Conventional ink and water balance concepts of lithography make the observation that ink and water are delivered to the plate by two different delivery systems, based on the supposition that ink and water do not mix.  It wasn't too long ago that ink train dampening was viewed with horror by the experts in the industry.  These experts insisted that direct to the plate dampener was the only proper dampening system.   A Proven Concept Ink and water can and do mix. Then evidence was provided showing that these earlier concepts were wrong.   Ink and water do mix (must mix) and that water is also delivered to the plate by the ink, not only by the water train.  Scientific tests proved the new concepts without any doubt.  But there may be some purists who will resist science, so let's examine some practical observations to illustrate the concept. All Areas Get the Same Amount of In

One of the most frustrating problems with the dampening solution that a pressman faces today in offset printing is edge-to-edge dampening .  Drying up on both ends of his product causes constant printing problems.  To explain the problem we must examine the structure of our roller configurations and the dampeners that are in use today. The Role of Exposure to Air Briefly, rollers rotate at very high revolutions per minute and are exposed to the press room atmosphere.  The centers of the rollers are sheltered from ambient air, while the ends of the rollers are exposed to this ambient air from outside of the roller train.  If you drew a curve of exposure to atmosphere it would show high atmospheric exposure on the roller ends and low exposure in the center.  One must realize that this exposure has a drying up effect on the rollers.  The higher the exposure the more we dry up.  One example is the recent innovation which uses air bars to blow air into the ink train to reduce exces

Managers Must Control Wasted Time and Materials   Controlling waste time and resources should be one of the skills that a manager must have to survive in our competitive world. From what I have seen recently, I am not too sure that managers really have a handle on that real world of cost allocations. What I have seen is a very intensive effort to reduce labor costs without understanding of cause and effect.   This effort starts with faster presses, which is normal, and thus continues into the crewing of those faster machines. In one recent press room change-over to higher speed presses crewing went from crews of over ten to a crew of six. Currently there is a drive to reduce the crew to five.   This concentration of effort to reduce crewing is typical in the industry today. It has the appearance of searching for the Holy Grail. The real kicker in this story is that this managerial focus is a throwback to the concepts of the early ‘40s when materials were cheap and the off