A modern design provides the smallest and lightest utility knife using ceramic blades. Ideal for everyday carry on keychain, wallet, zipper pull, or as part of emergency kit. 100% rust proof in salt water makes this ideal for boating or fishing activities.
Improved version of Kickstarter campaign that sold 1,500 Micro Knives. Now with better blade retention and using Black Ceramic Blade.
Ceramic Box Cutter Smallest EDC Knife Corrosion Proof Blade
EDC Ceramic Micro Knife $11.95 + Free Shipping to USA/CDA + $1.50 Extra for Shipping World Wide
Starting with an existing utility blade design the intent was to make it as small and light as possible. Pre-Production prototypes with a ceramic blade actually weigh less than 3 pennies or 6.5 gms. Length was determined by blade size and thickness of this cutting tool is only 3.5 mm. The blade needs to be held so that it would not accidentally become exposed, and ideally should be adjustable in terms of the length of blade opened for cutting.
I have been involved with the design and production of ceramic blades and knives for the past five years before passing the company into younger hands. It is exciting to design unique and expensive knives and when selling price is not important this is a relatively simple task. It has been much more difficult to create a low cost practical knife using a ceramic blade.
The design and production of an inexpensive practical knife to introduce the benefits of a ceramic blade to the general public has been a two year process. I did try to use bronze, titanium and carbon fiber, all non-corrosive materials, but these materials were not compatible with my design requirements of simple, durable and inexpensive construction. Precise metal forming or even extrusion molding could not maintain the required blade tension. 3D printing models were extensively used in developing parameters for an injection molding process where appropriate plastics could be used. It turned out that a two part molding process with ultrasonic welding could meet tolerances and durability in use.
The trapezoidal utility blade is one of the most commonly used blades in the world. In North America it is estimated that 40% of all homes have one or more blades and over 60% of businesses use them. Obviously a micro ceramic knife cannot serve in all general purpose tasks due to size and the brittleness of the super hard blade. The long lasting sharpness of a ceramic blade and 100% corrosion resistance does make this a better tool over time for small tasks and exposure to moisture.
A ceramic edge will not curl as a steel edge will when cutting tough material such as kevlar or the new ultra high density polyethylene ropes and lines now in use. The overall size and lightness makes it possible to have the micro knife available where a full sized utility knife would not.
While the standard white Zirconium Dioxide blades offer great improvements over steel blades we have found that the more expensive “carbonized” ceramic is worth the extra production costs due to increase hardness, strength and sharpness!
- The ceramic blade is the same size as the universally used Stanley blades with the exception that it is slightly thicker. (.8mm compared with .6mm for steel blades) Yes a steel utility blade will fit. The black ceramic blade is made by carbonizing the white blade in a second sintering operation. 50% higher production cost BUT results in a harder and sharper blade.
- Testing has shown that in cutting abrasive materials such as cardboard the ceramic blade will retain it’s edge about 20 times longer.
- The Zirconium Dioxide ceramic blade will cut Kevlar, and other tough materials such as the new “super ropes” and fishing lines better than steel as the edge does not curl and create burrs like steel blades.
- The ceramic micro knife body is injection molded in two parts. These are electrosonic welded to create the proper tension to hold blade in place during carry but permits in and out movement through thumb pressure. (We tried but were unsuccessful in creating a holder of bronze or titanium materials as the correct tension and sliding resistance could not be controlled.)
- Weight of tool with ceramic blade is 6.5 gms or .23 oz (= 3 pennies)
- Thickness is 3.5 mm. under ¼”
- Total length 2.5” with ceramic blade inside.
Moving Blade and Holding knife
While it seems obvious to me, someone is not going to visualize the forces to be employed. The blade is held inside the holder by spring tension from front and back sides AND a small wedge shaped area at the very front of the opening. It may be stiff the first few times and blade might catch on an imperfection inside the channel.
Moving back and forth a few times should loosen things up. Holding the rear of the ceramic utility knife, place your thumb at upper back of blade (not sharp) you can apply forward pressure to move blade out the front. Using a string, key ring, lanyard in hole at rear of knife makes this a lot easier.
This micro knife is too small to hold the way you would a full sized knife. Using a pinch grip, thumb and forefingers on opposite sides exerts extra tension on the blade so that it will not pull out when cutting things.
*Very little force in the pinch is needed to hold blade in open position. A 72 years old with minor arthritis has no problem with grip.
In addition to the tension on sides, once the blade starts cutting that force will make the blade try to tip upwards inside the channel and this again helps to hold the blade inside the holder. Same principle as holding a pen or scalpel blade the pinch grip provides the best fine control of the blade. Even with large chef’s knives the preferred grip is to have thumb and forefinger on blade just in front of the handle.