Question about using the worksharp knife sharpener

[joeyza]

I just got the worksharp and have to say I think its amazin for its price! 1 question I had tho is I don't understand how it is meant to give a knife a convex edge? I have sharpened a few knives already and they have turned out razor sharp but dont seem to have a convex edge like the blackjack neck knife I have that came with a factory convex edge. The belt on the worksharp revolves around 3 wheels and the portion of the belt where you put the knife is flat. So if the belt is flat at the point where it comes into contact with the knife, how is this supposed to give a convex edge? I have tried thinking about it but just cant picture how its meant to work. Any ideas about this would be appreciated!

 

[Brisket]

It is the slack in the belt that forms a curvature around the edge that creates the convex edge. It can be minimized or maximized depending upon the belt grit progression and pressure applied. A knife with a full convex grind is convex from the edge to the spine and you aren't going to duplicate that on the little 1/2" x 12 belt, but you can convex the primary edge. I know the Blackjack 155 isn't full convex, I just used the full convex example to illustrate the limitation of the Worksharp.

 

[OHALLUM]

+ 1 on what Brisket said. The belt is spring loaded so there is slack in it. There is no platen to work off of so any pressure on the belt results in some wrapping around the blade edge. If you freehand it without the blade guide, and sharpen up close with the blade edge trailing near the top roller, you can reduce the amount of blade wrap if you apply very light pressure. This will give you a more V grind and less of a convex edge.

Blessings,

Omar