Silicone Die Cutting

What is silicone die cutting?

Silicone die cutting is a process and technique for forming silicone. Usually, when using a silicone die cutting machine, the material needs to be placed under the die, and the machine will run to obtain the silicone product of the shape you need.Machines can continue to produce after operation, so most are used for large-scale production.

Types of Die Cutting

Flatbed Die Cutting

The operation process of flatbed die-cutting can usually be divided into several steps: feeding, advance, die cutting, waste stripping and laminating. 

Operational Process

Place the silicone raw materials on the unwind shaft of the die cutting machine. The material is pulled to the die cutting area by the conveyor belt, and the machine positions it by identifying the edge of the material to guarantee the accuracy of the cutting position. Then, the material is sent to the flatbed, and the die is vertically downward to cut the silicone into the preset shape. After the die cutting is completed, it is also necessary to remove the excess waste outside the product contour. Finally, the die-cut products are adhered to the carrier film.

Scope of Application

Generally speaking, this die cutting method is mainly suitable for solid silicone materials in sheet or roll form. Most of the products produced are of uniform thickness and relatively simple structure. These products are more suitable for processing by die cutting, such as silicone sealing rings, silicone gaskets, silicone insulating sheets, etc.

Characteristics

This die cutting method offers higher processing accuracy, lower mold costs and stronger production flexibility. For medium and small batch orders, flatbed die cutting reduces the cost per piece and improves the overall cost-effectiveness. Meanwhile, high-precision cutting guarantees the consistency of the products and also leads to higher product quality. If you want to produce products quickly, flatbed die cutting can rapidly create samples and accelerate the production cycle of the products. It can well meet your needs.

Rotary Die Cutting

Operational Process

Rotary cutters are suitable for cutting out the same linear silicone products.It is first drawn from the unwind shaft, through the die cylinder and the anvil roller, and then the raw material into the die cutting area of the machine. The core component of machine cutting is a cylindrical steel roller with many sharp blades on its surface. When the machine is running, the high-speed rotating die cylinder and anvil roller work together continuously to cut the material into the predesigned shape. After cutting, the fertilizer on the outside contour of the product is separated from the body of the product with the help of the machine.The formed products are covered on the carrier film and then collected again on the material roll shaft.

Scope of Application

Through the operation of the rotary die cutting, rotary die cutting is more suitable for large-scale, continuous production. For instance, it is used to produce a large quantity of silicone sealing strips, silicone sheets with uniform thickness, and a large number of silicone sealing rings and other products. These products are usually not complex in shape and have a relatively large single production volume. Moreover, this die cutting method has a higher production efficiency and can better meet your needs for large-scale and efficient production.

Characteristics

The advantages of rotary die cutting are mainly reflected in its high efficiency and continuity. Extremely high production efficiency is the core advantage of rotary die cutting.Rotary die cutting machine for continuous rotation, production speed is really fast, suitable for mass order production use. Compared with flatbed die cutting, rotary die cutting equipment has a lower degree of wear, generates less noise during production, and has less material waste. Most importantly, rotary die cutting can achieve stable control of materials, greatly reducing tensile deformation of materials and ensuring the stability of product dimensions. It can also achieve fully automatic continuous production, greatly reducing labor costs.

Laser Die Cutting

Laser die cutting is different from other die cutting methods.Strictly speaking, laser die cutting does not belong to the type of die cutting. Because laser die cutting mainly relies on laser beams to cut materials into different shapes rather than using blades.

Operational Process

To use laser die cutting, it is first necessary to draw the shape outline of your product on a computer using professional software. Of course, the manufacturer will set appropriate cutting parameters such as cutting speed and frequency based on the type, thickness, and color of the silicone in your customized product. The laser machine will scan the material surface along the predesigned shape. The silicone material evaporates or melts instantly in contact with the laser beam, thereby separating the product from the raw material.

Scope of Application

Laser die cutting is suitable for complex, soft and easily deformed silicone products, such as the production of complex cut-out products or extremely thin sealing layers in electronic products. If you want to customize silicone products with extremely high precision and flexible design shapes, laser die cutting is a very good choice for you.

Characteristics

Because laser die cutting does not generate pressure, it can better maintain the original shape and performance of the raw material, and will not deform or damage the silicone material. Moreover, laser die cutting can flexibly cut out the shape you want, without being limited by the complexity of the graphic. Compared with the cutting method using a blade, the products cut by laser die cutting have smoother edges, and it does not need to consider the wear and dullness of the blade. It can also be connected to the system to achieve a fully automated processing flow.

CNC Die Cutting

Operational Process

The operation process of CNC die cutting has achieved a high degree of automation and digitalization. CNC die cutting requires instructions to be passed into the CNC processor.Then the process starts, and the production equipment will gradually cut off the excess parts in a preset path, preserving the exact shape of the product.

Scope of Application

CNC die cutting is a supplement to traditional die cutting and laser die cutting. CNC die cutting is highly suitable for processing silicone products with large thickness, large size or three-dimensional processing. If the material of the product you customize cannot be cut by laser die cutting, you may also consider using laser die cutting. For example, some thickness of tens of millimeters of silicone pad, processing can use the CNC die cutting method, because laser and flatbed die cutting are difficult to deal with. If you want to customize a large gasket, the cost of using a flatbed die-cutting custom mold is high, while CNC die cutting can be directly engraved at a low cost and fast speed.

Characteristics

CNC die cutting does not require custom die-cutting tools, making it particularly suitable for small-batch production. It can also process materials of different hardness and thickness. Compared with laser die cutting, CNC die cutting is not restricted by material thickness and color. Moreover, this die cutting method does not generate heat during the processing, so it does not change the inherent properties of the material.

However, this die cutting method has low production efficiency and wastes more materials. During the die cutting process, the precision requirements for the die are high, so dull dies need to be replaced regularly.

Digital Slitter Die Cutting

Operational Process

Firstly, the silicone material is installed on the unwind shaft of the machine, which can make sure that the material enters the cutting area to remain flat and stable. After that, the material enters the slitting knife seat, on which there are multiple circular blades. The distance between the blades can be automatically adjusted according to the preset value. Then the material is continuously cut into multiple narrow strips of predesigned width through the cutting area. If the product you customize has a specific length, the device will precisely calculate the length of the material. Once the preset length value is reached, the device will cut the material, thereby obtaining a neat sheet.

Scope of Application

Digital slitting machines are suitable for processing large-width rolled materials into strip or sheet products, such as silicone tapes, silicone buffer strips, sealing strips, etc. Most of these products have simple shapes and do not require complex processing procedures such as drilling holes.

Characteristics

Digital slitting machines are often used for large-scale production of simple shapes. The slitting process of the equipment is continuous, with a very fast running speed and high operating efficiency, making it suitable for large-scale operations. A highly digitalized and automated production system can control the precision of your products within ±0.1mm or even higher, which can keep the consistency and high quality of products. Besides, digital production can shorten the line changing time and is suitable for small-batch and multi-specification production.

Steps of Silicone Die Cutting

Pre-production

Engineering Review

First of all, the engineer carefully studies the drawings of your customized product.They mainly focus on the key dimensions, tolerances, material structure, etc. of your customized product, such as which layer of material should be kept, which layer should be cut off, how to avoid material deformation, etc.

Secondly, which die cutting method is more economical and efficient should also be taken into consideration. If you are customizing a large quantity of standard parts, rotary die cutting is more suitable. If the product you customize is a small batch of complex parts, you may adopt flatbed die-cutting. If thinner products are needed, laser die cutting should be adopted.

Finally, according to the material size, use professional application software to wake up the product tight and reasonable typesetting. This can achieve the maximum utilization of materials, effectively control costs and reduce material waste.

Tooling Preparation

At this stage, the manufacturer needs to produce the corresponding dies according to the determined process. The new die must be tested on the equipment. Test whether the dimensions of the products cut out by the new die meet the production standards and customization requirements. Only when they reach the production specifications can they be used in formal production.

Raw Material Preparation

Prepare the raw materials for production. Before production, check the color, model, thickness and other aspects of the silicone material.All requirements of materials should be consistent with customer requirements. Place the material on the unwind shaft and set the operating parameters of the equipment properly.

Core Die Cutting Process

Unwinding and Tension Control

The material is led out from the unwind shaft. At this time, the tension control system of the equipment is very important, which controls the state of the material introduction. Neither loose nor too tight is the most stable state. Otherwise, the material is prone to problems such as inaccurate movement or tensile deformation.

Some devices are also equipped with an automatic web guide system. This device can detect the edge or center position of the material. If the equipment detects that the material position has shifted, it will adjust the position of the material to guarantee that it accurately enters the die-cutting area.

Precision Die Cutting

This stage is the most crucial part of the entire die cutting process.When the material is accurately fed into the die cutting area, the material is die cut into your custom shape under the action of the die cutting equipment.

Die cutting usually allows for either kiss cutting or through cutting. The difference between them lies in that kiss cutting can retain the protective film at the bottom of the material, which is convenient for product mounting and transportation. While through cutting requires all the materials to be cut through, it is more suitable for individual products that do not need a carrier film.

Waste Stripping and Lamitation

After the product cutting is completed, the material outside the main body of the product needs to be stripped. The waste material will be pulled up by the equipment, causing it to be separated from the product.These waste materials will be wrapped around a special waste rewind shaft.

Some products also need to have a new material attached after die cutting. For example, a layer of double-sided tape is laminated on the other side of the silicone gasket. In addition, for more complex products, it also requires secondary waste stripping or secondary die cutting.

Rewinding/Sheeting

In the end, the product will be neatly winding on the rewind shaft, ready to transport for the next procedure. For some products, the equipment will also cut continuous products into sheets, facilitating packaging and transportation.

Quality Control

On advanced die-cutting production lines, in-line visual inspection equipment is usually equipped. This kind of equipment can automatically detect defects such as the size, dirt and burrs of the products, and can automatically mark or remove defective products.

Moreover, quality inspectors will also take samples from the production line and use tools such as tensiometers and measuring instruments to test the dimensions and functions of the products, and finally generate inspection reports.

Post-production

If you have any packaging requirements for the customized products, the merchant will specially package the products according to your requirements, affix labels, and finally transport them.

Advantages of Silicone Die Cutting

High precision and consistency. Die cutting can achieve high-precision production. This high precision is crucial for the application of some precision electronic products. Moreover, once the parameters of the equipment are set properly, the die-cut products have a high degree of consistency, which greatly guarantees the quality of the products.

High efficiency and high production capacity. Highly automated and digitalized die-cutting can achieve ultra-high-efficiency production. This high efficiency also means high production capacity, which can meet the fulfillment requirements of your large-scale orders.

High-difficulty die cutting and forming capabilities. Die cutting can achieve complex shapes, sharp corners and fine cut-out patterns.Some products through the registered die cutting, it can also realize the production of complex composite parts in a process.

Kiss cutting process. This is the unique advantage of die cutting. The equipment can precisely control the cutting depth of the die, allowing it to penetrate only the silicone layer and other functional layers of the product while retaining the protective film at the bottom. At this point, the products are more convenient for automated transportation, packaging and subsequent mounting processes.

High production flexibility. Especially for flatbed die cutting, if the product needs to be changed, the manufacturer only needs to change the die and adjust the production program, and the line changing speed is fast. This is often used for the manufacturing demands of multiple varieties and small batches.

Limitations of Silicone Die Cutting

The initial investment cost for dies is high.For dies with complex shapes, huge sizes or special requirements, customization costs are high. Especially for rotary die-cutting, changing the die requires replacing the entire die cylinder. Making a precise die cylinder is costly and takes a long time. If you want to customize small batches of products, this production method will lead to high costs for individual items.

Limited design flexibility. Once the die is completed, the shape of the product is fixed. If there are any minor modifications to the design, the die will have to be remade. Modifying or remaking die not only delays the delivery time but also has additional costs.

Process risks and defects. When the die is worn or the parameters are inappropriate, burrs will appear on the edges of the product, affecting its appearance and usability. Especially for products with high sealing performance requirements, burrs may lead to the failure of the product seal. Besides, the initially sharp die will produce tiny dust during the production process. This is a problem that needs to be strictly controlled in the optical or medical industries.

Material waste. Even though optimizing product layout can improve the utilization rate of raw materials, die-cutting is essentially subtractive manufacturing. Wasted materials cannot be recycled. For expensive silicone materials, the wasted raw materials will undoubtedly increase the cost.

Effect Factors of Silicone Die Cutting

Material

The hardness and resilience of the material directly affect the difficulty of die cutting.Materials that are too soft will easily deform or tear. Materials with poor resilience may not be able to strip waste. The thickness of the material will directly affect the die cutting stability, leading to problems such as failure to cut partial material or damage to the bottom film. What’s more, the viscosity of the material will also affect the speed of die-cutting and the quality of the product.

Die Molds

The sharpness of the die is the most important influencing factor. Dull dies are the main cause of burrs and unbreakable cuts. Therefore, it is necessary to regularly inspect and maintain the die to keep it sharp. Secondly, the material of the die is also very important. When cutting sticky materials, a die that prevents sticking should be selected.Besides, the blade angle, the depth of die cutting and so on are influence factors.

Process Parameters

The pressure and tension control in die cutting will affect the quality and consistency of the product. The production speed also needs to be matched with the characteristics of the materials of your customized products, the state of the dies, etc. How to carry out waste stripping is also a difficult point. Unreasonable stripping of waste materials can cause the product to deform or tear.

Final Thoughts

Successful silicone die-cutting is a perfect combination of materials science and mechanical engineering. As a veteran, Legensilico has specialized in silicone products for many years and can provide you with the best customized silicone products. If you have any customization needs, please feel free to contact us.