Wednesday, November 21, 2018

Figuring The Angles!


If you use a knife there comes a time, regardless of the steel, that the edge needs touching up.  Many of us return our knives the company for resharpening or take them to a professional sharpener.

Even thinking of this brings to mind a childhood memory of an itinerant knife sharpener on the south side of Chicago.

He had a push cart that he walked behind and sang out “knife … scissor sharpening” as he traveled down the street.  It had little bells that tinkled and jingled as the cart rolled.  He would sit at the stone which was powered by a foot treadle and sharpen.  I remember my mother with a pair of scissors that needed sharpening as well as all the women in the neighborhood coming out to see this old man and his grind stone.



Not the same one, but similar


I always wondered where he came from and how he got into the business. 

Companies make all kind of sharpening aids.  I had a guide that clipped on the blade of a Buck knife and held it at constant angle.  I didn’t say correct, just constant.  Both sides are worn down from years of use.  I have a Lansky that also clips on the blade and lets you select one of several predetermined angles.  The Spyderco Sharpmaker currently has two predetermined angles, one for back beveling the blade (30 degrees) as you sharpen into thicker and thicker steel and their standard (40 degrees) for sharpening.  Of course you can use either angle for your sharpening your knife.

Some of us can hold a constant angle on a flat stone and simply select an angle based on their experience.  I’m not one of those, but I can free-hand a dull edge into something significantly less dull.

The Work Sharp sharpener comes with several different grit belts but the really attractive part is the dial-an-angle feature.  Simply turn a knob to a predetermined value and you have your angle.  It’s up to you to hold the knife against the supports to get that angle, but it’s not that hard.

powered sharpening
The numbers are the angle and you can swap different grit belts.  The system produces what people call an appleseed or hamaguri grind
Sharpening connoisseurs claim you should find a specific angle for the steel and hardness of your blade and your applications.  I remember a fellow collector, who had the resources of a world class lab at his bidding who addressed this question.  He purchased throwing knives from a single vendor to get the same steel and hardness, and sharpened them with many different angles and types of abrasive grits to determine the “best” angle and method.  Then he had to establish a reproducible cutting test that measured the friction through leather.  Scanning electron photomicrographs were taken of edges before and after testing.

 
I suspect he determined the best way to sharpen that particular knife and not the one in your or my pocket.

Still it’s the angle you need to know.  Audacious Concept, located in Lappeenranta, Finland has the solution for you.  It’s a little dog tag that has precision cut angles from 5 to 45 degrees by fives.  Simply slip your edge into each slit until you find the best fit.  Best fit seems to be when the edge wiggles the least in an angle.

And you get a beer bottle opener!
You can estimate values in between if two adjacent angles both seem to have the same wiggle.

This lets you set your sharpening system to the factory angle or what you have discovered for your knife and use. 

Sure, you could just select any angle, or you could engrave the factory angle somewhere on each blade.  You could keep a notebook with the name and description of each knife with the factory angle and your sharpening angle.  You could do a lot of things.

Or you could just buy one of these little dog tags and keep it with your sharpening supplies.






No comments: