Rotary Die Cutting vs. Flatbed Die Cutting: Which One to Choose?

Rotary finishing and flatbed die-cutting are both well-established processes with their own benefits, and certain projects will require a different finishing method. The more you know, the better equipped you will be to decide which process is best for your job.

Which process should you use?

The biggest factors to consider are, first and foremost, the material and its thickness. Usually, when cutting with rotary, you get a diagonal cut, depending on whether the material is very thick or not.

Servo-based machines can help you overcome some of the difficulties when cutting thicker substrates. With specialized rotary equipment, you can do speed ratios or you can time the entry and exit and vary the speed and control the tension very closely so that you can almost eliminate this problem and get a vertical cut on very thick material.

The thickness of the material is the main reason why people tend not to use rotary machines and have to do a particular job on a flatbed. The second major consideration is usually how long these runs take.

What is rotary die-cutting?

When you think of rotary die-cutting, think of high speed, high tolerances, and high precision. Depending on the complexity of the machine, rotary die-cutting can produce extremely complex multi-layer parts because it is able to perform multiple functions in the same processing cycle. As the material is pulled into the machine, the web is fed out of the unwind spindle.  From start to finish, the material can be laminated, cut, placed, and registered in a homogeneous process.  The roll goes in and the finished part comes out. Unlike flatbed die-cutters, there is no idling.  The material is cut and processed between the rotating cylinders. The cutting speed is measured in feet per minute as the material passes through the machine.

The most common rotary die-cutting machines use machined metal rotary dies.  These machines have precision machined cylindrical rolls called anvil holders.  The cutting is done through a matched gear precision machined die. Die cutting is achieved when the material is sandwiched between the sharp blade of the die and the smooth surface of the anvil base.  

The cutting action can be entirely through the material or something called a "Kiss Cut". Kiss cutting means that the die is machined to leave a small gap (literally the thickness of the paper) between the blade and the anvil.  This gap prevents the cutting paper or plastic lining from effectively 'kissing' rather than cutting the paper.  If you have ever seen a sticker, then you have seen a kiss cut. The rotary die cutter cuts the sticker form without cutting the release paper. That's why it's called a kiss cut.

Best for high-volume orders

Rotary die-cutting is a highly accurate cutting method that is very cost-effective when it comes to high volume orders and generates less waste than other methods.

What is flatbed die cutting?

Flatbed die-cutting machines use a flat fixed base and a movable head. The cutting dies are usually made from sharp metal strips called steel rulers, bent to match the contours of the parts to be produced.  The bent steel ruler is then embedded in a matching slot in the plywood cutting plate. The die can be fitted to the base or to the head.  When the machine cycles, hydraulic pressure is generated in the hydraulic cylinder which presses the head with the cutting die through the material.  Depending on the complexity, the base can be a plastic cutting plate, typically used to produce through-cut parts, or it can be steel in a precision flatbed die cutter.  

Precision flatbed presses can be cut through or kiss cut, similar to rotary cutters. Although slower than rotary die cutting, flatbed die cutters can open wide enough to handle material that is too thick to be cut by the rotary process.  The use of steel ruler dies makes flatbed die-cutting ideal for short-term orders where the cost of rotary dies is prohibitive. Finally, if the material is only available in sheets, flatbed die-cutting may be the only solution.

Ideal for: general cutting and small batch orders

With flatbed die-cutting, material shapes are stamped out using steel ruler dies and hydraulic presses. This method makes it easy to remove holes from parts and remove webs, while speeding up changeover times for greater efficiency.

Whether your cutting solution is rotary or flatbed, there are many variants and options available for both methods. A die cutter based on a good solution will be able to configure the most cost-effective process for your application. Remember, with advances in technology and automation, what was once considered impossible may well be a viable production process today.

Ultimately, you will need to work with your precision die-cutting specialist to decide which cutting method is best for your project.  IECHO is a rotary die cutter manufacturer. For more information and consultation, contact us here!