[GUIDE] 5 Ways to Improve Your Slitting and Cutting
How to improve slitting and cutting processes
The basic blade design for slitting or cutting any material, film or foil is essential. We are often asked to improve an existing blade design only to find that something is not optimal from the start. This text explains how to improve your slitting and cutting and the different methods we use to increase blade performance and durability. There are five ways to improve blade performance: design, coatings, materials, polishing and oil.
- Blade design to avoid dust, heat, flakes, chips and burrs
- Coated blades for longer durability and performance when slitting and cutting
- Materials - Solid Ceramics & Solid Tungsten Carbide
- Polished coated dished top and bottom knives for slitting metallic foil
- A small amount of oil for converters when slitting and cutting
- How can Sollex help you?
1. Blade design to avoid dust, heat, flakes, chips and burrs
The absolute first step in cutting any type of material is to determine the basic design of the blade. Dust formation is a sign that the knife has lost its sharpness. For a finer cut that removes dust, you need something sharper. Razor blades will give you the finest and most precise cut you can get. A dished circular upper knife that cuts against a bottom knife when shear slitting gives good durability but not very nice cuts. Try a circular dished top knife against the bottom machine knife. On the other hand, flakes, chips and burrs can be a sign of over-sharpened blades. If you get flakes, chips or burrs when cutting metal foil, try a larger grinding angle, or in other words, a duller knife.
Basically, having the right size, thickness, design and sharpening is the first way to improve your slitting or cutting process. Once you have found a good performing solution, it is time to think about how to improve the durability of your slitting or cutting process. Read more in blog post "Industrial Blade Maintenance: Extending Cutting Performance".
2. Coated blades for longer durability and performance when slitting and cutting
The use of coating techniques on the blade is Sollex's second step in improving a slitting process. A coating protects the blade edge and is much harder than steel. Rather than wearing down the blade design, the coating maintains the original design longer. In addition, coating changes the surface properties of the blade, its thermal conductivity and the cutting process.
Slitting aluminium foil with a ceramic-coated top blade appears to work as well as a steel blade. However, the true benefits of the coating on the cutting edge will only become apparent after prolonged use. By its nature, the circular top knife distributes the cut over a long cutting edge, giving it a long service life. A less sharp cutting edge will wear out at a much slower rate than the sharp top knife. Therefore, it is not certain that the coating will make the blunt blade last much longer than a circular top knife without a coating. However, if the circular blade is sharper, the coating will have a much greater effect on the durability of the blade.
On the other hand, coatings have a profound effect on the performance and durability of razor blades. A basic slitter blade may last 20 minutes when cutting tough abrasive film with white additives. The same blade with a ceramic coated edge, such as Slitter Blade Ceramic Coating 5K, will last two weeks. If the same film contains a lot of ink and printing, the fully coated blade Slitter Blade Full Ceramic Coating 5X will perform much better. For a completely different, thin, stretched film at high speeds, the durability of the edge is not as important as the friction of the blade. In this case, the Slitter blade zero-friction 5Z offers such low friction and cutting performance that it will last for weeks.
3. Materials - Solid Ceramics & Solid Tungsten Carbide
Coatings can really prolong performance and durability for a razor blade. However, the manufacture of the same design in solid ceramic or solid carbide can have a profound effect on durability. The hardness of solid ceramic and solid carbide will last much longer. However, it is not all about hardness. There is hard carbon of up to 6000 Vickers which is useless as a coating or solid carbide because of the way it reacts on a production line. Nor is it certain that the hard metal or ceramic will perform better than a coating. But, for example, when cutting hard, abrasive plastics such as PP, we know that the Slitter Blade Solid Tungsten Carbide 5V works wonders.
On the other hand, the Slitter blade solid ceramic 5C is designed for extreme performance and durability when cutting soft plastic film with very degradable properties. The blades are fragile and require careful handling. They are self-sharpening during use.
4. Polished coated dished top and bottom knives for slitting metallic foil
Coatings and materials change the topography of the ground edge, making the blade perform differently than when ground in plain steel.
In a test with a customer, we specially polished two top dished upper knives with ceramic coating to see the difference in how the even finer surface properties affect the cutting process.
We found that the mirror polishing of machine knives and blades worked really well when cutting thin metal foil. We have had similar results with the use of plotter knives and circular top knives in the medical technology sector. Polishing the coated edge gives an extremely fine topography which further improves the slitting and reduces flakes, burrs and dust.
5. A small amount of oil for converters when slitting and cutting
Sometimes rough edges, burrs and flakes can be avoided by adding a small amount of oil. When slitting or cutting a shiny metal foil such as aluminium or copper, or when you want a very fine topography of your material, oil can help.
We can ensure that the material stays smooth and doesn't get all messy when we cut it by putting a tiny bit of special oil on the cutting tool. It's like oiling a squeaky door to make it work better. This is because the organic solvent reduces friction at the point of contact between the slitting blade and the metal foil. This prevents the metal foil from stretching, which in turn prevents the formation of burrs and chips. In addition, the frictional heat generated during the slitting process due to the volatilization of the organic solvent is quickly radiated from the metal foil and the blade, and the heating of the metal foil is prevented, which is also considered to suppress the generation of burrs and chips. It also makes the material more rigid, resulting in a finer cut.
This trick is very useful when cutting metals that can easily become rough and messy. It helps to get nice, clean cuts without any burrs or mess. So, in simple words, we can use a special oil, silicone or lubricant to make sure the cut is smooth and clean.
This text is about how to improve the performance and durability of blades and machine knives. It emphasises the importance of correct blade design, the use of coatings to increase durability, the choice of appropriate materials and the occasional use of polish and oil for smoother cuts. The text also highlights that the choice of blade material can have a significant impact on performance. In summary, it's all about optimising knives and blades for better results and longer life.
How can Sollex help you?
If you are in need of blades or machine knives with performance and durability, Sollex is a good supplier. We have an extensive range of knives and blades in stock. Take a look at all our slotted slitter blades and other industrial razor blades like blades with 3 holes and small injector blades. We can also help our customers with blade design, coatings, materials, polishing and oils for improved durability and performance. Drop us a line or give us a call and we will try to help as best we can.