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So What's the "Brubacher Edge Sharpness Scale" (BESS)?
Here Comes the BESS
And it's about time. For centuries folks have been dragging their thumbs across sharpened edges and shaving hair off their arms in an effort to determine if an edge was sharp or not. While it's certainly debatable whether or not these kinds of anecdotal tests produce accurate and useful data one thing is certainly not in question and that's the difficulty in transmitting this kind of sharpness information to another individual in a meaningful way. With the advent of modern photography we could at least see evidence of the bald spot on the guys forearm but this is hardly enough information to come to any hard and fast conclusions regarding how sharp the edge was that fomented the localized alopecia. Even proponents and practitioners of the "hanging hair test" recognize that each individual's hair is likely to behave differently in a given test so if the results of such a test were to be reported, they must be accompanied by a hank of the author's hair in order to make the results relevant to others.
The BESS (Brubacher Edge Sharpness Scale) 0 -2000 gram pressure scale was designed to function as a clear and concise means of easily conveying sharpness data from one individual to another. This edge sharpness data has the same relevance to users whether they own sharpness testing instrumentation or not because the scale has been made relevant to all. Just as we know that ice is cold we know that razor blades are sharp and on the BESS "A" scale the sharpness level represented by a standard double edge razor is "0" value. The BESS "C" scale exists for electronic sharpness testers and for measuring edges that are actually sharper than a standard razor blade. Pictured below is a graphical representation of the BESS "C".
The graphic above is designed to give relevance to any user of the BESS. After, perhaps, thirty seconds of study one can gain insight into the quantifiable aspects of the BESS and then find relevance in those numbers. For example; you now know that the sharpness level (score) of a DE razor blade is 50 on the "C" scale and that a new cutlery knife is in the range of 275-375. If I tell you that I have two knives, one with a BESS score of 200 and the other with a BESS score of 800, you know that I am describing one very sharp knife and one quite dull knife.
Users and practitioners of the BESS are no longer constrained by the limits of physical and visual descriptions of sharpness. These users now describe sharpness levels with numbers. One could say that it is very, very cold outside or that the garden hose is frozen stiff. Or you could simply say that your thermometer indicated that the temperature is 17 degrees F. Which description do you find to be more informative and reliable? The BESS may be used for both internal and external purposes. Here is an example of internal usage; If a user who owned sharpness testing instrumentation were to find themselves with a knife edge that was imminently satisfactory to them with regard to sharpness (let's say it shaved hair from their arm quite readily) they could measure the edge of that knife and obtain a BESS score. For illustrative purposes let's say that score was 180. If he subsequently sharpened every knife to 180 then it would no longer be necessary for him to shave additional hair from his arm. If he were to then transmit his precise sharpening procedures and sequences to a friend who also desired knife edges in the 180 range then that would be one form of external use. Many industrial users now specify to their suppliers a BESS number for cutting and shearing blade sharpness levels then spot check those blades when they are delivered.. An example of external use.and then internal use.
BESS is administered by BESSU a non-profit organization which establishes standards and protocols for test media and instrumentation. Use of the BESS is free.