Maximizing Yields in the Bindery

by: Kevin Rickard

In our highly competitive graphic arts industry, labor costs, raw material costs, the bottom line and most importantly, client goodwill are on the firing line every time a job is produced. An effective quality assurance program and reducing spoilage are vital in maximizing yields.

Let’s first look at quality assurance from a bindery’s perspective. Suppose a printing company sends a $10,000 print job to a bindery for $1,000 of bindery services. If the bindery expects to net a 10 percent profit, it is accepting $10,000 of risk for only $100 potential profit. Since printers hold binderies accountable for their performance, the reality of the bindery business is that only a few bad jobs will destroy the financial performance of the company. In short, binderies, as well as printers, must do their work right the first time, every time.

Get Correct Information

Quality assurance begins by obtaining the right information about what needs to be done, how it should be done, and what acceptable quality standards are. All the parameters of the job should be precisely and completely defined. Binderies use the term “preflighting” to mean the process of obtaining and reviewing reliable and detailed information about every aspect of a job before setting up any manufacturing operations. Without proper information, the scheduler can’t plan the job and department leaders won’t know what is required.

Every bindery has produced jobs that it is embarrassed to admit came in its front door, let alone went out the back – yet the customer was delighted. Similarly, every bindery has produced what it thought would be award-winning work – but for some reason, the customer was disappointed. What can we conclude from this? Quality is whatever the customer needs it to be. On a job-by-job basis, binderies should make every effort to discover how customers define quality and adapt their internal standards to meet customer expectations. To accomplish this, at the very least, binderies need detailed purchase orders with written instructions and pre-production samples, bluelines or samples of prior jobs.

Setup

When a bindery has compiled all the information necessary to begin a job, the internal job order must be clearly written up in straightforward language so that every operator and supervisor understands what is required. After the job order is approved, but before production begins, a progressive series of approvals and signoffs should be collected. The operator who sets up a machine must be satisfied that it will produce what the customer wants, according to the job order and provided samples. Good standard practice is to have the operator run a small quantity of material, take it to a supervisor and ask for written approval. This supervisor should measures the pieces, examines them for imperfections such as blemishes, smudged ink, scratching and folding sequencing problems, and then verifies that all parts of the machine are functioning correctly. If applicable, bundle counts should be checked as well. When the supervisor is satisfied that everything is correct, this information should be sent to others involved with the job, including the customer service representative and quality assurance manager (if one exists) for final signoffs.

Production

It must be the primary responsibility of the machine operator to maintain quality control. Managers approve setups, but once jobs are running, operators are the ones with their hands on the throttle. The operator must carefully read job orders and understand all instructions pertaining to their particular function before loading the machine, producing product and packing pallets. Operators should constantly monitor their jobs and check their output lift-by-lift and bundle-by-bundle. In the unlikely event of post-production issues surfacing, a time-stamping process is recommended to create a relevant production history and allows any problems to be isolated.

It also is recommended to provide employees full authority and responsibility to stop production if they have any doubts about quality. Operators should have a comfort level to go to their supervisor at any time to request a second opinion. If a supervisor instructs an operator to proceed with the job, the supervisor should then assume responsibility by signing and time-stamping a sample. Operators then keep at least one signed sample as proof that they have been instructed to proceed. Then, production continues as long as quality doesn’t further deteriorate.

Reducing Spoilage

Good spoilage planning is the second thing we are going to look at to maximize yields. Every significant printing job will incur some spoilage. Since spoilage rates aren’t consistent, it’s impossible to predict exactly how many sheets will be wasted during any given production run.

Many things cause bindery spoilage. Paper characteristics such as thickness, curl, brittleness, grade and coatings are very important. In general, thin sheets are more easily damaged than thicker ones. For example, when planning saddle stitched jobs, 4-page signatures should be given twice the spoilage allowance of 16-pagers, if the paper is the same weight. Exposure to too much heat can make paper and ink brittle, resulting in excessive cracking and increased spoilage. As the job runs, accumulating press powder and varnish buildup will gradually change the grip of the fold rollers, changing the fold position. Humidity will make paper limp, but excessive dryness can cause static. Either condition might hinder sheets from moving squarely into plate sections – again increasing spoilage.

Common Causes of Bindery Spoilage

Varnish. Varnish is one of the bindery’s worst enemies and best friends. On the one hand, it generally doubles the amount of spoilage during folding, but on the other, it certainly reduces marking problems. Varnish buildup changes the coefficient of friction of the fold rollers. Inexperienced operators tend to change fold settings instead of cleaning the rollers. In most cases, cleaning will cause the fold position to return to its original setting.

Shipping. A lot of “bindery” spoilage occurs during transportation from the pressroom to the bindery. When shipping printed material between facilities, some damage is inevitable. Not surprisingly, the amount of damage is directly proportionate to the care given during shipping preparation and the skill levels of those involved. Sometimes packing choices comes down to the lesser of two evils. Applied improperly, banding wire can cut into and damage sheets. Stretch wrapping without corner boards will bend corners of the sheets, causing downstream machine-feeding problems. The key to minimizing transit damage is carefully and tightly containing product so it won’t vibrate during transit or slip off the pallet.

Wood pallets and tops. Many wood pallets and tops are made from new, or “green,” wood with very high moisture content. Without a barrier, moisture will migrate from the wood to the paper. This moisture migration can destroy up to ½-inch of otherwise perfectly good printed material.

Mixing paper stock: Mixing brands, grades or even different lots of the same paper will increase spoilage. If a pressman runs out of stock and substitutes a similar sheet, expect different performance levels in the bindery. Paper lot changes should be clearly marked on skids and kept separate as the job transfers between departments. For example, if a cutting operator finishes cutting a job and mixes different papers without identifying which is which, a folding operator will have no idea why a fold position suddenly moved and why the crossover, which was perfect ten sheets ago, is now 1/8” out of alignment. If the operator doesn’t waste a lot a sheets making the necessary adjustments, a lot of time will be wasted – or very likely both. Even worse, if an unmarked skid from the first lot remains, the machine will have to be adjusted back to the original settings. In general, whenever different stock is used on a job, plan for 1½-percent additional spoilage allowance.

Quality assurance is an excellent way to maximize yields in a bindery, however, you have to reduce your spoilage in order to reduce waste and save money. These two things are very important items to consider for every job. Don’t waste more than you need to and provide customers with a job that is of great quality and done right the first time. Your company will stand out and it will show in your bottom line.