How to sharpen convex grind by hand?

[Naphtali]

How do you sharpen a convex grind knife using Arkansas stones, and better yet, using a Lansky-type fixture sharpener?

Although I don't believe it matters, material is D2.

[Joel]

The proper way to sharpen a convex edge is to strop it backwards accross your stone, like you were stropping a razor.  I use an 800 grit Japanese water stone to touch up mine, just so I don't get too lazy and always do it on the grinder.  Never saw any need for a finer grit, though others use 1000, 1200 etc.  D-2 is a tough steel, and as such resists abrasion(in this case sharpening), which is what it's designed to do.  As such, you might start with your medium arkansas, using a goodly amount of pressure...depending on how bad the edge is,  and work up to the fine.  If it's quite dull, gentle stropping will take you the rest of your lifetime with a steel like that.  You have to start with the top of the convex grind on the stone, and then as you pull it toward you, rock to the edge.  I'm sure you've use a leather strop before....it's kinda like that  motion.  I've NO idea how you would do it on a Lansky.  I gave mine away years ago, and my picture of the process is now a trifle hazy.  Then again, Nothern Freight sells(or used to) a little 1" X 30" belt grinder for around $29.00........That and either a 600 or 700 grit belt will get the job done in about 2 minutes.  You use the slack part of the belt between the top of the platen and the top of the grinder wheel .  Then either buff off the wire edge on a leather stop(they also sell leather belts that fit that grinder at Knifmaking supply houses), a piece of damp cardboard, or a buffing wheel of some type, if you have one.   Good luck, and don't give up.  That convex edge is infinitely superior to the flat beveled sort.

[Naphtali]

Joel:

Many thanks for a clear, concise reply.

Sharpening is nearly impossible to mess up permanently. If my sharpening job is a poor one, do it again. And, from your reply, it appears that as the sharpening process wears away blade, the edge configuration remains constant -- that is, the edge DOES NOT become thicker and less efficient with use.

Okay, now for a difficult question: Is there available two listings for makers of knives with convex grind -- one for production or limited production makers, one for custom makers?
***
Parenthetically, interesting side effects of the grind appear to be:

1. If you're paranoid about corrosion, as I kind've am, the act of sharpening automatically removes it.

2. Paying extra for a mirror finish is a pointless expense. First resharpen and -- BEHOLD -- finish is gone.

[Will52100]

Like Joel said, sharpen backwards.  I use a Norton fine india stone for all my sharpening.  I sharpen backwards then remove the wire edge with a couple of light forwards strokes.  If I want scary sharp instead of a more agressive working edge then I make a couple of passes with a fine arkansaw stone.

If you've got a flat or convex blade, sharpening will make the edge get thicker over time.  The way to handle that is to decrease the sharpening angle so that you basicly thin the edge back down to about where it was new.  Unless you've realy battered the edge up and need to take nicks out it will take many many years of use to wear a knife down very far.  Most people over sharpen and wear a blade down.  Only take as much off as needed to get the blade sharp again.  On a steel like D-2 a fine cermanic hone would probably be a good idea to use to "freshen" the edge up lightly.  

A sharpener with a guid like the lansky is OK, but it limits your ability to sharpen and is like training wheels on a bike.  Keeps you from falling over but limits you too.

Best way to get pretty decent at sharpening is to get a cheap knife like Old Hickory and practise sharpening free hand.  It'll be a lot less frustraiting when you go to work on your good knives.

[Joel]

The proper way to sharpen a convex edge is to strop it backwards accross your stone, like you were stropping a razor.

You might have misunderstood that statement, Napthali.  I meant start at the top of the convex edge grind,not the top of the blade convex grind, if it has one.  I flatgrind and mirror polish all my blades. When I convex grind the edge, there is a definite demarcation noticiable between the blade and the edge; mainly in that the edge isn't as polished as the blade. About the only ones I know who grind the whole blade to sharpen are the Scandanavians who use a flat grind that ends in an edge with no bevel.  It's mostly used on those knives they use for working with wood.  It's also gotten popular with the "roughing it" set who use those style knives when in the woods.  They call it a Scandi grind.

As far as who uses a convex edge on their knives, the most obvious maker is Bill Moran and many of his students; the edge is known as a "Moran" edge by many folks.
There are a number of makers who use it, especially among the blade forgers; although to be honest I can recall reading about them, just can't remember all the names.  The most famous user of the convex blade/edge was William Scagel.  Marble's knives are convex ground as were/are Blackjack Knives.  I've heard they're getting back into business again.

You should realize that prior to the beginning of the "machine age" ALL implements that were sharpened used a convex grind and/or edge.  The exceptions being woodworking knives/chisels etc.  The trouble with that grind is that it can't really be done well by a machine; it requires a person sharpening by hand.  Factories found it much easier(cheaper) to just run the blade along a grinder and get the flat edge bevel.  No skill involved. The reason that it's not often used today is that it requires a certain amount of skill to maintain, and those factories who have tried using it received so many complaints that they switched back to a flat grind.  Marbles and Blackjack were the exception, as are some knifemakers(such as myself for one).  My whole concept of a knife revolves around the sharpest possible edge. Everything else I do when making a knife is secondary/supports that idea.  I will not put a flat edge on a knife, and any knife that I buy is immediately modifed to convex.  I've never had a knife returned to me,but then people who buy custom knives are usually willing to learn to properly sharpen them.  For those who can't ,I(and other makers) offer to re-sharpen the knife for free; charging only postage.  That seems to work.

[Karl B. Andersen]

I'm with you all the way on the convex edge!
I attended Ed Fowler's "Seminar of the High Performance Blade" last summer in Wyoming, and now all I do is the full convex blade. It's tested as being the toughest to compromise.
At the Chicago Custom Kife Show this past summer I bought a Warthog V-Sharp sharpener made in Africa with the "real" diamonds, not just industrial grade diamonds. That thing puts and edge on a knife that'll scare ya'! And does it quick, and is adjustable.
Anyway, I'm all about CONVEX!