3 Tips For Doctor Blade Care and Chamber Maintenance

Although they're a crucial part of flexographic and gravure printing, the importance of doctor blades and their chambers is often overlooked. With proper care and maintenance, damage to the anilox roll can be prevented and, money lost to ink and substrate waste will be reduced. By following a few simple rules for doctor blade care, it's possible to get the most out of both the blades and chambers, which will save time, money and headaches.

We spoke with four experts who gave great advice for doctor blade and chamber care. Johnny Stamey of Daetwyler; Marion Bobo of Performance Design; and Ken Theriot and John Hirko of Flexo Concepts offered key tips for converters to get the most out of their blades.

1. Talk to the Manufacturer

One of the best ways to prevent damage to the doctor blade or its chamber is to communicate with the manufacturer about the guidelines for care. First and foremost, Stamey says it's important to make sure that the correct amount of pressure is being applied, which can be monitored by a gauge on the chamber. Bobo suggests checking with the manufacturer to determine the end of life of the blade tip, which is different for each printer.

Some other aspects that Bobo points out are:

• Making sure the ink deck is kept clean
• Using an ink filter
• Installing a strong neodymium-type magnet to attract blade particles

2. Out With the Old

Although it may be tempting to clean blades, it is not advised. Theriot explains that doctor blades are a low cost consumable, they are easy to replace and optimal print quality can be achieved if they are replaced with each new job.

Steel blades in particular should not be cleaned, since they can become very sharp and ultimately dangerous, Stamey says. He also says that since every print shop is different, a method should be determined for replacing blades, and whether it's daily or weekly, it should be consistent. Stamey goes on to explain that if an anilox is changed "plus or minus more than 100 line screen," the doctor blade should always be replaced.

3. Choose The Chamber Wisely

It's not enough to choose the proper doctor blade, and pressure, and when to change the blade … the proper chamber needs to be chosen to ensure that the system is running optimally.

"The doctor blade material is only as good as the holder," Bobo says.

Again, it's important to talk to the manufacturer to understand the best chamber for the blade needed, but it's also important to optimize the system by using the chamber designed for the type of blade material: steel vs. plastic.

Chambers also need to be replaced — albeit much more infrequently than blades, from five to 10 years — and they need to be cleaned. Hirko says that if the chamber isn't cleaned and the blade doesn't fit properly as a result, the blade will wear unevenly.

Care and Maintenance of Doctor Blades and Chambers was originally published in the April issue of packagePRINTING.