Welcome to Eversharp's Manufacturing Section.

(1) Stainless Steel Importer Warehouse
A lot of attention is given to the raw material since it directly influences the subsequent processes and it is the main "ingredient" for the cutting functionality.

Rolls, Sheets and Strips of Stainless Steel
Broad sheets of stainless steel are imported from Japan, Germany, and other locations from around the world.  We deal in various grades of material each with their own composition, for example: 420J2, 1.4034, 440A, 440C, or AUS8. 



2) The Stamping Facility 

Single Stamp System
Large sheets of raw stainless steel are divided into manageable hand held strips. They test these sheets in 3-5 spots to ensure the thickness is consistent and the tolerance is acceptable. These smaller sheets are fed into a stamping machine that has a specific cutting die attached to it, which etches out the shape of the product a single stamp at a time. A separate machine is used to punch the screw hole, and yet another piece of equipment stamps the logo from a customized logo plate.

Automated Stamp System
The automated system uses large rolled sheets of stainless steel that are pressed out and fed into a larger stamping machine, where the shape is stamped, the screw hole is punched, and the logo is stamped simultaneously.
 

(3) The Heat Treatment Plant

Vacuum Heat Treatment 
Blades are secured in a special hanger, which is placed in a cleaning tank filled with a cleansing chemical that purifies the steel.  The blades are then put into large, electrically controlled, vacuum heat treatment tanks where all of the oxygen is extracted.  The heating process goes through has three levels before it gets to its maximum heat of 1200ºC plateau. The cooling or quenching process is done quickly and in a controlled environment. The rapid control of the cooling rate is extremely important for the interior consistency and Rockwell construction of the raw material. At this point the items go to a sub-zero freezing container where liquid nitrogen cools the container to -150ºC, which can eradicate any changes the material may have undergone during heat treatment. The items go into a computer controlled re-treatment tank that monitors the temperature gauge for stability, which lasts for 4 hours.

Traditional Heat Treatment
Although Eversharp does not typically use this method because of its lower qulity level there are a couple of things worth noting.  Stacked blades items travel by conveyor belt into a heat treatment furnace, which is fueled by ammonia, where the material is heated at about 1100ºC. After approximately an hour in the furnace the slow cool down process begins, which could take 3 - 5 hours.


(4) The Back & Side Grinding Operation

Back Blade Grinding
Blades are laid out in a row side-by-side on a conveyor belt and undergo five separate grinding belts of different degrees of coarseness (from roughest to smoothest).

Side Blade Grinding
A rack of 50-100 units are done simultaneously by being brought up to a grinding belt to clear away the blemishes on the sides of the blades.

(5) The Grinding & Polishing Operation

Inside Blade Grinding & Polishing
Blades are arranged on a metal shelf inside a large grinding machine. Water circulates around the system and a grinding stone rotates over the shelf for about 10 minutes to clear nicks and surface debris from the inside blades.

Bevel Grinding
A single blade is placed in its mold and when the machine is activated it shears off a beveled area from the outside of the blade. Water circulates to wash away particles of steel, reduce friction from extreme heat and prevent the shape from changing. The machine can be set to a certain degree or bevel angle.

Knife-Edging
This uses the same machine as bevel grinding but it uses a different shearing mold and setting for the cutting angle (a finely honed edge can be produced).

Hollow Grinding
Using a German grinding stone, a gentle indentation is made on the inside blade. This is designed so that only the knife edges come together for optimal cutting performance.

Serration
Single blades are inserted and then pressed forward onto a rotating grinding stone.




(6) Plastic Handle Injection Factory 

Standard Injection System
From a consumer point of view, it is often the handle that is the key aesthetic feature that attracts them to a certain product. This makes the handle injection process an important one.

Eversharp does PP, nylon, TPE, TPR, polycarbonate and various other plastic injection.  We also work with overmolding (the process of combining 2 different plastics together on 1 handle).

A vat above the injection equipment is filled with the ingredients for the proper plastic composition. The water is dried from the plastic to purify it and then it is released down into a set of tubes where it is heated at over 200ºC. The liquidified plastic enters the spout of the mold, so the operator places each blade into the handle cavities.  When the portal is closed and the injection is triggered the mold clamps together and the liquid plastic is released from the tube and goes through the channels until it fills the empty spaces of the handle mold.
 

(7) Assembly, Engineering and Final Quality Control

Eversharp - Adjustments and Enhancements (On the Floor) 


Eversharp - Assembly and Testing (On the Floor)
Single blades with handles arrive and are sent to a sloping machine that produces a slight bend in the blade - different products with different thickness' and lengths need different bends for optimal cutting performance. An operator aligns and connects any accessories and uses a hand drill to unite the screw and nut at the correct tension.

Re-workable pieces are sent to a grinding machine where a worker finds the problem spot and grinds off any hitches or impediments and then re-tests. This is also where any items that need additional inside, side or back grinding and polishing would be sent. A separate machine is used to polish, clean, and automatically even out the blades with a grinding brush and high- pressure water spray. There are also bevel grinding and knife-edging machines if any items need to be re-worked or adjusted. A drill operator can position finger rest holes and threading into the handles if necessary. The facility also houses a piece of equipment that does high-tech, micro-serration using a German grinding stone.


Eversharp Engineering - R&D and Quality Control
The engineering office uses CAD programs for creating graphic images and industrial drawings. Another system is especially for 3D SolidWorks designing.

The QC engineers choose random samplings (1%) from the beginning, middle and end of the production lot. They hand test the run, smoothness, and feel of the shears. They then extract a thin cross section of stainless steel from the test scissors.  The steel material undergoes  advanced scrutiny to tests the molecular consistency and hardness. If the sampling rate fails to meet a certain level the lot will be sent back to the sub-contractor to be re-done.

A steel grain tester makes use of a diamond head that scans across the grains of the steel and looks for unacceptable discrepancies, while a handle stress tester can judge the strength and durability of the plastics used in the handle.


Eversharp - Warehousing and Shipping
 

Eversharp - Project Management 

(8) Other Related Processes

There are various other stages that may or may not be intermingled in manufacturing. For example, the handle mold maker uses CNC technology to generate new molds, while a die cutter can produce dies for different blade shapes and sizes. Other operations could include: satin finish & vibration polish workstation, parts & accessories factory, rubber materials & accessories supplier, and the packaging operation.