Edge Trailing or Edge Leading?

[ricklee4570]

I have been watching the Master, Murray Carter, put some fine edges on his blades. He uses the edge trailing technique. Anytime he uses his 6000 grit fine water stone, it is in the trailing (almost like stropping) motion.

Has anybody ever done any testing to see if it really matter which way you sharpen the blades as to edge retention?

 

[GrinderMcgee]

I work with my limitations as an intermediate level sharpener. That means experimentation but mostly my manual sharpening motions are edge leading.

It is recommended to use water stones edge trailing I believe to avoid cutting the softer medium.

 

[HeavyHanded]

I use a fore and aft motion with equal pressure when raising a burr. When getting rid of the burr I gradually decrease the edge trailing pressure and finish with just edge leading. They work about the same, but you'll raise a burr faster edge trailing and have a hard time getting rid of it without moving to an edge leading stroke. As you get to the finer abrasives it matters less and less (look at how popular convexing with sandpaper has become), but it still requires more diligence to completely remove the burr when edge trailing. Waterstones can be used either/both way(s).

 

[zyhano]

yes, experiments have been done by John D. Verhoeven,
Emeritus Professor Department of Materials Science and Engineering of Iowa state university.
You can download his paper for free: google his name and 'experiments on knife sharpening'

they have not been done specifically with edge retention in mind but it was found that edge leading actually produced a smaller burr..

 

[unit]

they have not been done specifically with edge retention in mind but it was found that edge leading actually produced a smaller burr..

I was going to post the same results...but they were based on my subjective observations and not scientific study. I could attempt to rationalize my findings (which seem intuitive to me) but why bother?

I would speculate that edge retention relative to leading vs trailing will be impossible to test given the variable in technique and ability to test edge retention for the average (or even above average) sharpener/user/tester. That is just a hunch though...but it seems logical that either method is removing metal through abrasive action to create an edge, and both should work quite well. As long as your technique is good, trailing or leading should both produce results good enough as to be indistinguishable from an edge holding POV.

 

[kelbro]

Just a hunch but I would guess that edge leading could possibly provide better edge retention. This hunch is based on pix that I have seen of steeled edges where it looks like the metal is 'pushed' back up the bevel. But like unit said, nearly impossible to test.