PROFESSIONAL BINDERY EQUIPMENT SERVICE

NOTICE:  KNIFE SAFETY! Knives are DANGEROUS!!!

They are heavy and very sharp, even after use.  Keep the edge away from your body and keep the area clear of other persons when handling knives.  Never touch the cutting edge!  To prevent personal injury and damage to the knife, always keep knives in their holders with screws tightened.  You are aware of the dangers, but others may not be.  Never attempt to hone, polish, or service the knife in any way, always send your knife to a professional knife sharpening company for service.  Failure to follow safety procedures may result in severe lacerations or dismemberment. REFER TO THE OWNERS MANUAL THAT CAME WITH YOUR MACHINE FOR INSTRUCTIONS ON HOW TO INSTALL OR CHANGE THE KNIFE BLADE IN YOU CUTTER. If you are not comfortable changing the knife, have a qualified field service technician change the knife for you.

Call toll free for service: 877-416-5550

Knife Blade Life

Knife blade life, or the time between sharpening, can be affected by many factors.  One important factor is the type of paper being cut.  Abrasive paper, such as recycled paper, soft paper such as newsprint paper, and bound books can all significantly shorten knife blade life.  Also, if the knife depth is set too deep, the knife will cut too deep into the cutting stick and can dull the knife blade.

A standard knife can last anywhere between 2,000 and 5,000 cuts before it needs to be sharpened.  Cutting soft paper (such as newsprint paper) or paper with high post-consumer recycled content can cause the knife to need sharpening after only 2,000 to 3,000 cuts.  Cutting pure paper, such as bond paper with no recycled content, or hard paper can allow the knife to be used for as many as 5,000 cuts before it needs to be sharpened.  In all cases, the operator should continually check the quality of the cut to determine when the knife blade needs to be sharpened.  Some characteristics that indicate a blade needs sharpening are: 

• The knife hesitates or stalls while making a cut.

• The sheets are not all cut to the same length (usually the top few sheets are longer than the rest of the sheets - this is sometimes called “draw”).

• Cut marks appear on the cut face of the paper.

• The profile of the cut (side view) is not perpendicular to the table.

• The cut does not appear straight when viewed from the top.

• The knife makes a “rougher” sound as it passes through paper.

• Nicks are visible on the cutting edge of the knife.

KNIFE BLADE STEEL

Generally there are (3) kinds of knife blades available.

STANDARD STEEL: this blade is the cheapest blade and may only be heat treated to harden the edge. They generally last about 8 hours before they need sharpened.

HHS: this blade has an HSS (HIGH SPEED STEEL) in-lay build into the blade, this give a sharp cutting edge that will last (2) to (3) times longer then the standard steel blade. This blade cost more then the standard steel blade and is the most popular blade in production in most binderies.

CARBIDE: this blade is the most expensive blade and has a carbide in-lay. This blade may last (20) time longer then the standard blade. It is more expensive to have sharpened but the lost lasting characteristics out weigh the cost of the blade. The carbide is very strong but brittle, it cuts very clean for a long time but chips easily when handled roughly.   

Cutting Stick

A worn cutting stick can affect the cut quality of the bottom sheets.  When this happens, the cut stick can be rotated.  Usually, the stick should be rotated one or two times between knife sharpening.

Bevel Angle

Most problems encounter with cutting are mostly due to operators using a dull knife, most shops do not replace the knife soon enough. But…the bevel angle ground will greatly affect the performance of the cutter and the quality of the job being cut. 

Generally speaking most shops use a “General Purpose” angle and fight it when cutting materials that need special knife blades. The following information is a general idea of the differences in angles and pressures. Most cutter manufactures have specific information for there particular machines, refer to your owners manual for this information.

Most cutters come with some type of clamp pressure control. It may be a little confusing when you read the dial or pressure gauge, try to think of it in terms of LOW – MEDIUM – HIGH. Make a note of what setting the job cut good at for the next time. Don’t forget dull knifes will also affect what pressure you need to get satisfactory results.

STANDARD BEVEL KNIVES

DOUBLE BEVEL KNIVES

Knife Care

• To prevent corrosion, knives are coated with light oil.  It should be REMOVED WITH CARE.

• While removing or installing a knife, be careful not to allow the sharp edge bump against the machine.  Nicks will result.

• If a knife bolt is damaged, replace it.

• Always keep knife bolts securely tightened.

• Always use the heavy-duty knife bolts and washers provided by the manufacture.  Failure to do so could result in scratching or marring of the clamp face.

• Store knives in a dry environment to prevent corrosion.

• Never attempt to service a knife in any way, send it to your "knife grinder".

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