The purpose of the grinding machine is to sharpen the edges while the polishing machine cleans up the edges by removing any imperfections. Both the grinding and polishing procedures are incredibly important. Grinding the edges is what makes the edges sharp so it will cut the hairs right off.
The polishing step smooths out the edges by removing any burrs or stray fragments from the cutting edges. DE blades need to have sharp but smooth edges to ensure they can cut the hairs without cutting the skin. One feature without the other renders a blade unusable and possibly dangerous. At this point in the manufacturing process, the product that started as a long, dull strip of soft metal is now thousands of sharp individual DE razor blades. They are not done yet though!
Now they need to be coated and treated with a variety of lubricants and finishes. The first coating applied is typically a chromium based coating. It is applied to the entire blade but is intended to ensure that the cutting edges stay hard and resistant.
Next, a non-stick coating is sprayed on. The last thing you want is for the blade to cause a lot of friction, you want the blade to just glide across your face. The non-stick coating helps reduce the amount of friction between your face and the blade which helps prevent skin irritation and razor burn. Lastly, the blades are submerged into an oil-based solution that helps give it some added protection from corrosion. Cave painting even show that Neanderthal men practiced shaving by scraping hair off with rough implements likes stones, flint and clam shells.
But in , a Frenchman named Jean-Jacques Perret invented the first ever safety razor. His company, Gillette, began selling these disposable blades in Though they only sold a modest 51 razors and blades in their first year, by , sales rose to 90, razors and 2. Razor blades are periodically exposed to high levels of moisture and that means they need to be made from a specially-made, non-corrosive steel alloy.
The grade of steel must be hard enough to allow the blade to hold its shape, but it also need to be malleable enough to be processed. The preferred type of steel is therefore called carbide steel.
The first process in razor blade manufacturing is therefore the mixing and melting of the components in the steel. One patented combination of elements used in stainless steel blade construction includes carbon 0. The plastic portions of a safety razor include the handle and blade cartridge, or portions thereof, depending on the razor design. These parts are typically molded from a number of different plastic resins including polystyrene, polypropylene, and phenyleneoxide based resins as well as elastomeric compounds.
These resins are taken in pellet form and are melted and molded into the razor components through a combination of extrusion and injection molding techniques.
For example, in making the handle for their advanced shaving systems, Gillette uses a coextrusion process which simultaneously molds an elastomer molded over polypropylene to create a surface that is easy to grip. Razors may contain a variety of miscellaneous parts which help hold the blade in place, guards which cover the blade during shipping, or springs or other release mechanisms which facilitate changing of the blades.
These pieces are molded by similar processes. The more sophisticated brands include a lubricating strip made of polyurethane, or other similar materials, that is impregnated with acrylic polymers. These strips are mounted on the head of the razor, in front of the blades. The polymer film absorbs water and becomes very slippery, thus creating a lubricating surface that helps the blade glide across the surface of the face without snagging or cutting the skin.
All finished razor components must conform to tight specifications before they are released. For example, blades must meet a designated hardness rating and contain a certain amount of steel.
Gillette blades must meet a standard knows as Vickers hardness of at least and a carbide density of particles per square microns to avoid rejection. The equipment itself operates so precisely that Gillette measures its reject rate in parts per million. Similarly, molded plastic parts are closely inspected by operators with lighted magnifying glasses to check for loose flashing or rough edges; they alert technicians when problems are discovered.
In addition, razor components are checked by a computerized vision system which compares a critical dimension to a reference. Razor manufacturers like Gillette are constantly designing new and improved shaving systems. Their commitment to improved materials science continues to produce blades of increased hardness that are capable of sustaining sharp edge for more shaves. Advanced head design allows the blades to contact the face without cuts or nicks. They are also constantly updating their manufacturing equipment.
The future manufacturing techniques also improve efficiency in molding and stamping operations. Gillette claims they are twice as fast as they were 10 years ago and have fewer defects. Panati, Charles. Extraordinary Origins of Everyday Things. New York: Perennial Library, Gillette Company.
Toggle navigation. The plastic portions of a safety razor include the handle and blade cartridge. These parts are typically molded from a number of different plastic resins, including polystyrene, polypropylene, and phenylene-oxide based resins as well as elastomeric compounds. Razor blades are made from a special corrosion resistant blend of steel called carbide steel because it is made using a tungsten-carbon compound.
The manufacture of safety razors involves First making the blade cartridge by die stamping the carbide steel and then welding the blades to steel support members. Simultaneously, the plastic components are extruded or injection molded and readied for assembly. The blade cartridge and plastic ports are automatically assembled at workstations that use vacuum lines to orient and hold the small blade ports in place during transport and insertion.
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