By Team Technifold USA
As users increase the speed on a saddlestitcher (or any piece of bindery equipment,) they’re likely to see more and more defects as the speed increases. There are many components that make up an automatic inserting, stitching and trimming line, each designed with operating specifications and limits. If any single component is slightly worn or not set correctly, it will prevent the machine from running at its maximum designed speed. Lots of little defects and weaknesses can add up to big losses in productivity.
The stitching head is one especially critical area for proper operation of a saddlestitcher at any speed. Even the simplest of newer stitching heads is a complex piece of equipment which, if not properly handled, will cause slowdowns, poor-quality stitched books and machine downtime.
In a conversation with Dave Double of Double Equipment, which specializes in bindery equipment repairs, including servicing of stitcher heads, it was brought to light the seven common but costly mistakes that stitcher operators and bindery managers make with their stitcher heads.
1) Using the wrong lubricant. Several common heads use a one-way bearing in their wire-advance system. Operators often use the wrong grease which, at higher speeds, results in varying leg lengths in the stitch. This leads to a frustrating troubleshooting expedition where the operator is trying to ‘fix’ a head that simply requires the correct grease.
Also, stitcher manufacturers usually recommend light machine oil and not the automotive oil which often is used. Be sure to use precisely what is recommended.
2) Using the wrong amount of lubricant. Any stitcher operator who’s been around a while has made this mistake – put too much oil somewhere on the stitcher head and the next few thousand books are a nightmare! Excess oil makes its way through the head and through the rest of the machine. In extreme cases the only solution is to remove the head for disassembly, cleaning and proper oiling.
All that typically is required is ONE drop at the proper location and at the proper interval. If the recommendations say one drop per eight hours of running, make sure that it’s not two.
3) Using the wrong wire gauge for the job at hand. Two of the most commonly used wires are 24 and 25 gauge round stitching wire. They are good all-around wires for most commercial bookbinding and print finishing applications. But if the operator stitching a 3/16″-thick book, or slightly heavier, the 25 gauge is approaching its limit. Problems can arise when near the limit and running at high speed. If the operator goes beyond the thickness limit, he or she is almost certain to encounter new problems.
When stitching an extra-heavy or extra-thin job, be sure to use the best size of wire for the job at hand. It is not common to saddlestitch books beyond 1/4″ thick, but if an operator does and runs into problems, don’t forget to check wire gauge.
4) Using the wrong wire gauge for the stitcher head. Each stitcher head has its own suggested limits on wire gauge. Be sure to check the limitations of the wire gauge for each particular saddlestitcher.
5) Using inferior wire. Wire quality varies considerably among manufacturers. Some factors that affect stitching wire performance are tensile strength, consistency of wire size, cleanliness, resistance to flaking, type of coating and type of alloy.
For instance, an inexpensive galvanized wire may start to flake and/or leave excess wire shavings when cut inside the stitcher head. This, in turn, will clog the head and cause premature wear on numerous internal parts. It also can make it difficult to get a properly formed stitch at higher speeds. Generally speaking, a tinned wire or a premium galvanized wire will run better, with less flaking and a more consistent coating, cleanliness and strength. If a facility does enough stitching, consider the larger 70# spools equipped with a de-reeler. These are not wound as tight as the smaller spools, so there is less variation due to changes in the wire curl.
6) Lack of regular servicing. Stitcher heads need regular maintenance, lubrication and service. If a finisher or binder doesn’t have someone on staff who is qualified to rebuild and repair stitcher heads, send them out regularly to someone who can. It is money well spent that will keep the stitcher running smoothly.
7) Instruction manuals that never get opened. Each model has its own special requirements and peculiarities. It’s been said a person can learn either through wisdom or suffering. There is wisdom gleaned from reading the manual.
There have been instances when operators have transitioned to a different saddlestitcher, needed to install a new stitcher head and simply didn’t consider the differences in the saddlestitcher. This can cause enormous damage to the machine and head. Installing the wrong head can turn into hundreds or thousands of dollars in repairs.
No matter which stitcher head is being used, be sure it’s set correctly to give a good cut, consistent wire draw, equal leg lengths, proper clincher and clincher alignment, and correct compression.
Most bindery equipment operators like to have a performance edge available to them when they need it, especially if they want to go home early! Although running at maximum speed is not always the best way to get maximum yield, it sometimes is both possible and necessary. On those occasions when a bindery must run at maximum speed, it’s nice to be able to do it without gremlins like those mentioned above slowing operations down. The good news is that these stitcher head tips are simple to follow.
Thank you to Technifold USA for its assistance with this article. For more information, visit www.technifoldusa.com.
