Sharpening directions

[TobyB]

Idle thought occurred to me as I walked home from the butchers ... which direction is right or the best for the blade against a stone, steel or whatever?

I watched 3 butchers each with their own technique for sharpening a knife ... one held the knife still pointing away from him and pulled the steel along its blade ... one held the steel vertically and pushed the blade down onto it ... a third held the steel vertically point down on the table and pulled the blade ...

Which got me thinking about how we sharpen all of our tools - knives, chisels, plane irons, etc. I think when most people use stones (oil or water), "scarey-sharp" films/paper, etc they "pull" the blade, with the sharp edge trailing. And it's the same with using a leather strop. But with most power grinders, wet or dry wheels, or belts like the Sorby ProEdge, the cutting edge leads into the grinding medium. But I remember seeing an Asley Isles demo of a grinder running "in reverse" bringing up a very sharp edge on their carving tools ...

So ... does it matter which way the abrasive moves ... towards or away from the cutting edge ... and if it does ... which is better?

 

[Harbo]

I do not think it matters - it's keeping a consistent angle that is important.
Grindstones normally grind away from you to prevent dig-in and there is less chance of cutting into abrasive films if you pull towards you.

Rod

 

[mtt.tr]

It actually does make a diffrence.

A) leaves a sharper edge byt weaker and can snap.

B) leaves a not so sharp edge as it makes it saw tooth like.

I use and angle on the stone in between about 20degrees from A. A is also a good method for getting a good edge on very coarse stones not fine enough to shave but good enough to pair pine with out it smashing out i know this as my college only stone is a 400g hmm.