David, work shap convex sharpening are made on a slack belt. The pressure you use decide how the belt grind away material from the edge.
If your knife have a convex edge in for example 4 degrees and your pressure against the belt if just as hard that the belt follow the 4 degree sphere it will be grinded perfectly in 4 degrees.
If your pressure are just a little harder the belt will grind hard on the cutting edge and the backbevel and the cutting edge will get a big change in angle very fast. The cutting edge will be sharp, you cannot see the change, you will probebly dont feel the change in edge angle.
Over time this will make your edge angle so high that the knife do not penetrate material - and you must regrind the edge back to its starting point.
My tool Chef can meassure the convex sphere, with the help of the built in protractor you can meassure how many degrees the convex sphere holds.
Thomas
If your knife have a convex edge in for example 4 degrees and your pressure against the belt if just as hard that the belt follow the 4 degree sphere it will be grinded perfectly in 4 degrees.
If your pressure are just a little harder the belt will grind hard on the cutting edge and the backbevel and the cutting edge will get a big change in angle very fast. The cutting edge will be sharp, you cannot see the change, you will probebly dont feel the change in edge angle.
Over time this will make your edge angle so high that the knife do not penetrate material - and you must regrind the edge back to its starting point.
My tool Chef can meassure the convex sphere, with the help of the built in protractor you can meassure how many degrees the convex sphere holds.
Thomas
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