Cutting is the process of cutting large format paper or cardboard in sheets into smaller pieces to obtain printed products of the required size. For this, most printing houses use guillotine-type machines. The special beveled design of the knife and its high degree of sharpening allow you to work with large volumes of paper without losing ground in terms of productivity. A subspecies of cutting is flattening (English flat – flat, even) – this is a transverse cutting of roll paper or cardboard into sheets of the required format. At the output, the sheets are stacked on pallets of the required size and then transported either to the printing machine or sent to the warehouse.
Let’s talk a little about cutting. This is a process in which a finished product is separated from a rectangular printed sheet of paper using a wooden stamp with metal knives. The die-cut contour of the finished product can be given absolutely any shape, everything is limited only by the imagination of the client or designer.
Features of cutting in the printing industry
In all printing houses of the world, cutting takes place in exactly the same way) First, a program is set according to which the machine will cut the sheet. Then paper or cardboard is put into the machine. The machine is equipped with photocells that prevent the knife from dropping when the paper is leveled under it. Next, the paper is pressed with a press (so that the foot does not go and the squint does not turn out on the last sheet) and the knife is lowered.
It is worth noting that the table in the car has special holes with metal balls in them. This is done so that when moving the paper on the table, it does not break and get damaged. The knife in the machine moves along a curved line, which provides a perfectly even cut, without crease of the paper fibers.
What is the difference between cutting and punching?
Most customers do not see the difference between punching and punching. The bottom line is that punching paper or cardboard down to the substrate is die cutting, and cutting through is punching. To make it easier to understand the difference between these processes, imagine a beautiful curly holiday card with holes made in it. Represented? So, the contour of the postcard is die-cut, and the holes in it are a die-cut.
Die Cutting Types
There are few types of carving, only three. Let’s dwell on each of them in detail.
Die-cutting with tie-downs (batch cutting, batch cutting)
A fold-over is a small pack of sheet-prints of one small format. With such a die-cutting, a stack of sheets of the same size is forced through a steel sharp cutting ruler with a complex closed contour, and the cut products come out from the back side. It is used for die-cutting labels and envelopes. This is a fast and fairly efficient method of production. Its advantage is that after such a procedure, no burrs remain on the edges of the product.
Rotary Cutting
Often used in narrow web printing presses. Die-cutting cylinders are made of solid steel by machine or manual processing. Exactly the same steel is used to make knives for cutting paper. The starting material (paper, cardboard or film) passes between the cutting cylinder and a smooth, heavy cylinder, which is called the support cylinder in the printing industry. The cutting cylinder carves, cutting through the material. This type of cutting is good for printing labels using the roll-to-roll technique.
Laser Cutting
This cut is used in digital printing. The programmable unit of the device contains a laser that cuts through the printed material along a predetermined contour. Laser cutting usually comes after the printing process, but there are large format machines that can combine it. Great for making inscriptions from colored films, postcards, exclusive calendars, clothing labels.
Die-Cutting (Punching)
Die-cutting is a process necessary for giving a figured shape to a flat sheet material. Produced using punching dies , which are used to punch holes and slots of various shapes in printed sheets (blanks).
For high-speed die-cutting on rotary equipment in automatic lines, rotary dies are often used. Their cost is much higher. Than the cost of flat ones, since their manufacture is more laborious, but this is compensated by the fact that they can operate at higher speeds (tens of thousands of products per hour) and withstand up to several million cycles.
Before shapeless sheets of cardboard suddenly become convenient and economical packaging, they must go through several more stages of processing. One of these stages is cutting.
In other words, die-cutting is a process that gives a figured shape to a flat sheet material. All this happens with the use of punching dies . They are used for making holes and slots of various shapes in the lined blanks ( sheets of cardboard ).
At the same time, cutting means cutting holes on any material, whether it be paper, cardboard or plastic sheets.
The speed of the dance machine depends on the type of die. It is plywood, where holes are made in the right place.
To date, high-speed die-cutting on rotary equipment uses rotary punches. They allow you to work at higher speeds (about tens of thousands of products per hour), and their service life is longer than that of their predecessors. However, the cost of such a form will be noticeably higher, which, in other matters, pays off when working with this type of die.
Give a Shape to Finished Element
With the help of a punching machine, you can not only cut out certain shapes from the workpiece, but also give shape to an already finished element. For example, cutting along the outer or inner edge of the product, applying to crease (pressure on the cardboard to produce a more convenient fold along already given lines), scoring (cutting on the surface of the cardboard / scratching the fold line in order to facilitate folding the cardboard into the box), etc. .
The very process of preparing directly for the manufacture of the form takes place in several stages:
- Preparation of the material from which the form will be made.
- Installation of the die.
- Material application.
- Directly the process of cutting the desired shape from the workpiece.
- Evaluation of the result obtained (in this case, the product is either sent further or rejected and recycled).
At the same time, the possibilities of modern die-cutting provide a large field for imagination in the manufacture of molds. Now the most demanded on the market are original packaging products, especially with regard to festive packaging. At the same time, those custom packaging manufacturers who are not afraid to experiment with the shapes and sizes of the packages produced show imagination and an original approach in manufacturing packaging boxes noticeably benefit.