How to cut gaskets quickly and easily: gasket scissors, machines, and other tools
Seals are essential in many applications—from automotive to construction. Choosing the right tool for cutting seals is critical to ensuring precise, clean cuts, which translates into the durability and effectiveness of the seal. In this article, we will discuss various methods for cutting seals — including seal-cutting shears, machines, and other tools — to help you choose the best solution for your needs.
We invite you to take advantage of Power Rubber’s precision cutting service for rubber and silicone seals — we fulfill orders based on technical drawings or customer‑specified dimensions. Contact us by phone at +48 22 292 40 24 or +48 505 16 03 03, by email (Power|PowerRubber.com| |Power|PowerRubber.com), or via our contact form.
Types of Seals
Seals come in many materials, shapes, and sizes, which makes it necessary to use the proper cutting tool. The choice of tool mainly depends on the material of the seal, as well as the precision of the cut you expect. Different tools are suitable for cutting rubber seals versus silicone ones. Let’s take a closer look at some common types of seals.
Silicone Seals
Silicone seals are characterized by high temperature resistance and flexibility. To cut silicone seals properly, you should use appropriate tools such as:
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A precision utility knife or scalpel made of high‑quality metal — ideal for thin sheets and small parts; allows precise cuts when using a very sharp blade.
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A cutting plotter or oscillating knife — used for series production or more complex shapes; yields clean, repeatable edges without deforming the material.
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Waterjet cutting — the most accurate method for thick or complex silicone seals. A high-pressure water jet provides an ideally smooth edge without affecting the silicone’s structure.
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Laser cutting — less common, mainly for thin sheets; requires an adequate filtration system, as fumes may be generated during the process.
When cutting silicone, avoid dull tools that can stretch or tear edges. Precise cutting ensures correct sealing fit and retains leak‑proof properties.
Rubber Seals
Rubber seals are widely used because of their flexibility and sealing ability. To cut a rubber seal, some commonly used tools include:
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A segment knife or utility knife — for simple shapes and thin rubber sheets (up to about 2–3 mm).
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Steel die (die cutter) — a popular solution for mass production; allows reproducible shapes quickly while maintaining high dimensional accuracy.
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CNC oscillating knife — enables computer‑controlled cutting of complex contours, removing the need for die molds.
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Waterjet cutting — recommended for thicker rubber or complex geometry; does not cause deformation and ensures perfectly clean edges without burns.
It is important to cut rubber seals carefully and at the proper angle to avoid uneven edges. For thicker rubber seals, a cutting machine may prove more efficient, ensuring uniform and accurate cuts.
Ordinary scissors or hacksaw blades are not recommended for cutting hard rubber, as they may cause jagged or deformed edges.
Assembly Seals
Assembly seals often require precise cutting to fit perfectly to a given surface. Depending on the seal’s material, you may use seal‑cutting shears, a knife, or a specialized machine. Before cutting, it’s important to measure and mark the cutting line precisely to ensure the seal fits ideally during assembly. A properly prepared surface and accurate measurements are key to success.
Tools for Cutting Seals (Silicone & Rubber)
Seal‑Cutting Shears
Seal‑cutting shears are indispensable tools in any technical workshop, service center, or production plant where precise trimming of rubber and silicone seals is needed. They allow quick, accurate adjustment of seal dimensions, which is critical during installation and maintenance of technical joints.
Professional seal‑cutting shears should have sharp blades and an ergonomic handle for comfort and full control over the cut. This allows you to achieve clean, even edges without fraying the material, which directly influences seal integrity and the aesthetics of the finished joint.
When choosing shears, pay attention to the blade material. Models made from high-quality stainless steel ensure durability, corrosion resistance, and long service life—even with frequent use. Such shears are ideal for cutting thinner rubber, silicone, EPDM, or NBR seals used in industry, automotive, hydraulics, and construction.
Due to their functionality, seal‑cutting shears are useful in installation, servicing, and workshop tasks where precision and speed matter. The right tool allows obtaining the exact shape and dimension of a seal without needing cutting machines, making them a practical and reliable solution in daily technical work.
Seal Cutting Machines — CNC Plotter, WaterJet Cutting
Seal-cutting machines are professional tools that ensure high-quality, precise seal components, especially in serial production. Such machines can cut seals from various rubber compounds with different thicknesses.
Using a seal‑cutting machine is essential when high precision and repeatability are required. Depending on the model, the machine can automatically trim seals at specified angles, which is helpful when installing complex seals. These machines are commonly found in specialized shops.
CNC Plotter Cutting
CNC plotter cutting is a modern method used in the production of rubber and silicone seals, offering utmost precision and repeatability of shapes. This technology uses digital control of an oscillating knife, enabling accurate reproduction of even the most complex contours without needing die molds. The process is fast, economical, and ideal for both prototype series and short production runs.
CNC plotters can cut materials such as NBR, EPDM, SBR, Viton® (FKM), or silicone VMQ, providing smooth, clean edges without damaging the structure of the material. This technology minimizes waste and shortens lead times. CNC plotter cutting is favored by industries that value accuracy, repeatability, and the ability to produce custom‑sized seals under demanding technical requirements.
WaterJet cutting is an advanced technology used in the manufacture of rubber and silicone seals. It delivers exceptionally clean and precise edges without affecting the material through heat. The process uses a high-pressure water jet that can cut thick and hard elastomer compounds—such as NBR, EPDM, SBR, Viton® (FKM), or silicone VMQ—with great accuracy.
The advantage of WaterJet cutting is its ability to handle materials of varying hardness and thickness without risk of distortion, scorching, or microfractures. This technology works particularly well for technical seals, flange gaskets, and prototype parts where maximum dimensional precision is required. Because the process is digitally controlled, it ensures repeatability and minimal material waste. WaterJet cutting is a preferred choice in industries where precision, quality, and seal reliability are paramount.
Seal Cutting Techniques
Hand Cutting Seals
Hand cutting is a basic method using simple tools like seal‑cutting shears or a utility knife. This technique suits trimming small quantities of seal where ultra-high precision is not required. It’s important that the cutting shears or knives be of high quality to ensure a clean result and avoid fraying the material. Manual cutting is commonly used in seal installation, where speed and ease of use matter. This method works especially well for rubber and silicone seals.
Cutting Seals from Sheet
Cutting seals from sheets requires specialized tools and techniques, often using die cutters or stamps to achieve precise cuts. This method is suitable for mass production of seals with repetitive shapes. The material from which the sheet is made is critical — it must be compatible with the chosen cutting tool. Sheet cutting is essential in many industries where high quality and consistency are required.
Electric Tools for Cutting Seals
Using electric tools such as jigsaws or band saws is an effective way to cut seals from various materials. Machines provide greater precision and speed when shaping seals, especially for thicker materials or complex shapes. The key is choosing the right blade for each type of seal — different blades are needed for rubber and for silicone. Electric tools are indispensable in professional workshops where productivity and accuracy are essential.
Material Selection and Its Impact on Cutting
Choosing the Seal Material
Selecting the appropriate material for a seal is crucial for its functionality and longevity. You must consider the operating conditions of the seal — such as temperature, pressure, and exposure to various chemicals. Rubber and silicone each possess their own specific properties and suitable use cases. A properly chosen material ensures a good seal and long-term performance. When selecting, it’s advisable to consult a specialty shop.
The Influence of Material on Cutting
The material of the seal directly influences the cutting process. Rubber and silicone require sharper tools to avoid frayed edges, while sheet materials may require a cutting machine. The type of material determines which method is most suitable—whether simple shears suffice or a more advanced tool is needed. Choosing the correct cutting technique is key to achieving an accurate end product.
Examples of Seal Applications
Seals are used across many industries and everyday life. In automotive applications, they are essential for sealing engines and other components. In construction, they are used for sealing windows and doors. In hydraulics and pneumatics, seals ensure the tightness of connections. The use of a seal depends on the properties of the rubber compound chosen and the operating conditions the seal must endure. Proper seal installation is pivotal for ensuring the correct functioning of any device or system.
Power Rubber’s Precision Seal Cutting Service (Rubber & Silicone)
Power Rubber specializes in professional cutting of rubber and silicone seals using modern technologies such as WaterJet and CNC plotters. Using precise processing methods, we ensure perfect reproduction of shapes and dimensional accuracy per the client’s technical documentation. Our technological capabilities allow the execution of single prototype orders as well as mass production for customers in machinery, automotive, food, and chemical industries.
We cut seals from various materials such as NBR, EPDM, SBR, Viton® (FKM), and VMQ silicone, adapting cutting parameters to the hardness and thickness of each material. We offer comprehensive service — from technical consulting and project setup to final delivery of high‑resistance, durable seal elements.
Feel free to contact us to discuss your project or request a quote: by phone +48 22 292 40 24 or +48 505 16 03 03, by email (Power|PowerRubber.com| |Power|PowerRubber.com), or via our contact form.