Thread: Blade Confusion

Hi all. I'm getting confused on all the type of straight razors blades. I understand some but have questions about like: What hollow ground means in its variations?, is spike point and square point the same?, can a wedge be a round point ? and how can you tell the difference between a wedge and a concave blade by a picture (it seems hard depending on lighting)?

Is there a document out there that has all about blades?

Thanks,
John

Originally Posted by mrcleanhead

What hollow ground means in its variations?

Simply means the sides are concave to some degree. The degree of concavity is expressed as half-hollow, quarter-hollow, full hollow. There are no real standards on the actual level of hollowness, this is only an approximation. There are also grinds like frameback grinds that are kind of their own separate level of grind.

There is a long-running debate here as to whether wedges must have flat sides or if a slight concavity (less than a quarter) is ok. Part of the nomenclature problem may be because some log-splitting wedges have slightly concave sides as well.

Originally Posted by mrcleanhead

can a wedge be a round point ?

Sure. The point shape is orthogonal to the grind.

Originally Posted by mrcleanhead

how can you tell the difference between a wedge and a concave blade by a picture (it seems hard depending on lighting)?

Well, this depends on how flexible your definition of wedge is :-) Hone wear can give you some clue, as can reflections if the blade is shiny and the photographic environment was kind.