Blade geometry

[jazzrabbi]

Can anyone explain to me the difference in cutting ability between flat ground and hollow ground blades? Are they intended for diferent types of cutting?


thanks

 

[Buzzbait]

The cutting differences between these two grinds are not a big deal. Both have secondary edge bevels, which can be sharpened at similar angles, thus negating much possible difference in cutting efficiency. The thickness of the blade behind the edge bevel can also be very similar.

The flat ground blades tend to handle lateral torque much better, because the steel is thicker across the blade. Flat ground knives are very popular for tasks where prying and other non-knife duties are called for.

Hollow ground knives, tend to retain their good cutting efficiency over repeated sharpenings, since the thickness behind the edge bevel does not change significantly. Flat grinds cut worse and worse over time, as you repeatedly sharpen them.

 

[jazzrabbi]

Good explaination. Thanks.

 

[AlphalphaPB]

Wait, if there's no secondary bevel on the flat ground, it should retain the same amount of steel behind the edge, right?

I mean if you keep the edge of the blade like this: \/ then any amount of sharpening won't thicken the edge.

If you grind in a secondary, then repeated sharpening will lead to an increased amount of metal behind the edge.

For a hollow ground knife, depending on how large the grinding diameter is, you'll see some thickening, but I agree with BuzzBait, the hollow nature of the grind will save you from some thickening.

I'd like to ask, does anyone *not* sharpen with a secondary bevel on hollow ground blades? Sharpening would be a big pain that way. "Time to break out the ol' grinding wheel!"