This is a laser cutting die which is used for die cutting and die scoring. If you look around your kitchen or bathroom at the products you buy - almost all labels cartons and wrappers involve die cutting with a die that looks very much like the one above. This one is for a small cosmetic carton we produce for a client. What is so amazing about the die is that despite being made of wood and steel - it is the digital file incarnate. In a process invented about 25 years ago - the electronic dieline in Adobe Illustrator is used to guide a powerful laser beam that cuts a channel through the a special board material. Usually 8 ply marine plywood - this is an extremely flat and dimensionally stable material. The hi power laser burns all the way through at the exact width of the laser.
Although the laser could of course trace a very intricate pattern - steel rules (for scoring and steel knives (for cutting) need to be bent to the shape of the channel and thus are mostly limited to gentle curves and squarish joints. Even the bending of the rules are done with a CNC machine (computer controlled) but the end result is all analog goodness. The last step is old world - a craftsman hammers the rules into the channels, seating them against a steel counter and then carefully glues in blocks of "ejection foam" which is the red material in the upper photo. A die like this would be good for hundreds of thousands of impressions. On very high volume die (think beer carton!) where the units needed are in the millions, the die is pretty much the same although the base may be a special fiberglass board and the knives will be seated in channels that have a quick release - allowing the die to be "re-knived" quickly and easily.
The die cutting operation is straightforward: the sheet is pulled into the machine and the paper is cut or scored as the cutting plate (the base) comes into contact with the die. The make ready involves getting everything lined up as intended and then "spotting up" or putting down strips of thin tape to bring the cutting plate up to the correct height to cut through the material.
All the machines are heavy steel and often weigh several tons or much more depending on the size. Two popular designs are used by most of them: either it operates like a gigantic clam shell closing on a hinge or the two plates are brought together in parallel with the force of an enormous eccentric providing the power.
For the graphic arts geeks among us or the curious there is a very good explanation at the following website of a Swiss company called Bobst which has long been one of the premier die cutting equipment manufacturers in the world. Started in 1890 by Joseph Bobst they make die cutting and gluing machines used the world over to produce packaging.
If for some reason the link below is broken due to the company making updates - you could just explore the site! You can read about the process and see what the machines look like. What is amazing is that you can go into a printing or packaging shop in LA, Chicago, London, Paris or Beijing and you will likely find a Bobst die cutting machine at work!
www.bobst.com
Our carton production serves mostly health and beauty companies although we do some specialty food and beverage work as well. The work is often intricate and demanding but we love helping our customers put the final product on the shelf.
-Sean
