Best Practices: Die, Anvil and Cylinder Care and Maintenance

Some of the most important pieces of equipment package printers and converters use also happen to be some of the most fragile. Yet, when it comes to the care and maintenance of dies, anvils and cylinders, many print shops fall short of keeping these crucial pieces of equipment at their peak performance.

Among the key things to avoid are dings, dents, and dulling.

Wade Fouts, vice president of sales for Wilson Manufacturing frequently sees dies being run using too much pressure. Whether it’s a flexible die mounted on a magnetic cylinder or a solid rotary die, it should be run using the least amount of pressure possible, while still maintaining a quality cut and impression, says Fouts.

“One thing I often see is press operators putting the die on and just turning up the pressure, regardless of the material they’re cutting and the configuration of the die,” Fouts explains. “Every die requires a different amount of pressure.”

Once an operator has determined the lightest level of pressure that will keep the die working well, there will eventually come a time when that pressure needs to be turned up. Dies wear down over time, so when this occurs, increasing the pressure slightly to a “level 2” amount is expected.

Still, Fouts says, as the die is in motion and puts pressure on its bearers, heat is generated, which causes the steel to expand. This thermal expansion, Fouts says, also increases the pressure on the die.

“If that pressure that was initially set at 1,000 pounds, it might be up to 1,100 or 1,200 pounds, strictly due to thermal expansion,” he explains. “It’s not because they increased the force of the screws, but because of growth of the steel. When that happens—in a perfect world—the operator would back the screws off and take it back to the original 1,000 pounds and continue to run it.”

Properly lubricating the bearers on each end of the die helps minimize thermal expansion, he says.

Anvil Awareness

“Your anvil and your die work as a team,” Fouts continues. “So if you have a diecutting problem you have to determine which part of the team is causing the difficulty. They share equal responsibility.”

A Wilson Manufacturing anvil cylinder

Fouts recommends implementing a maintenance schedule to keep anvils in good shape. One of his customers keeps an extra set of anvils for each machine. Once an anvil has been in use for six months, it is swapped out for the backup and is resurfaced in preparation for the next rotation.

A Third Member of the Party

The widespread use of flexible dies adds a third component to the mix—the magnetic cylinder. Michael Wilks, product manager for printing products at Bunting Magnetics, explains the first step of keeping magnetic cylinders performing well is simply keeping them clean. And all you need are your bare hands and a piece of tape.

A magnetic cylinder from Bunting Magnetics

Wilks says the first step is to wipe the cylinder across its surface in one direction. He warns not to wipe back and forth because the goal is to get all of the debris located on one side. Then, a piece of masking tape or duct tape can be wrapped around the end of the cylinder with the debris to remove all the unwanted material.

Another essential element of cylinder maintenance, Wilks says, is keeping them properly stored. Magnetic cylinders should always be stored in their original boxes with a lid, he says. This way, no airborne debris will find its way to that cylinder.

“So many times I’ve gone into printing shops and pulled cylinders off of shelves and find they’re stored without the lids on them,” Wilks says. “If you put that cylinder on a table and you roll it upside down, it’s incredible how much stuff falls out!”

Storage solutions

Fouts says there are also certain procedures that must be adhered to for die storage. Of particular importance are the knife-edges on dies. Like many fine edges, these are very fragile and even the slightest nick can cause enough damage to affect the diecut.

For solid rotary dies, Fouts says, the end bearers should rest on wood or plastic V-blocks so the blades are suspended, not making contact with any surface. Fouts says all too often he finds dies in the field that are being stored on top of shop towels or another padded surface. This may seem like good enough protection, but Fouts says you never know if there’s anything in that towel that can cause damage. And, the die is free to move, which can also cause damage.

Flexible dies, much like magnetic cylinders, should be stored in their original boxes, Wilks says. But another best practice he has observed in the field is the use of large plastic bags. Dies are placed in these bags, which are then hung on a rack and can be categorized for easy identification.

“The plastic bag does a number of things,” Wilks says. “One, it protects the knife surface because the plastic itself is fairly thick, and second, it keeps moisture away. If it rains outside and the humidity inside the plant goes up, the dies are all packed inside plastic bags. They’re dry and not exposed to the air.”

Despite the importance of proper maintenance, Fouts says many print shops have a ways to go in improving their current practices. He says because it is so important, Wilson Manufacturing offers a complimentary die maintenance education service to its customers, helping ensure they are up to speed on how they can keep their equipment performing well.

“Everybody who comes into contact with the dies should be educated in the proper techniques for handling them.” pP

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