A Probably Stupid Q...

[cotedupy]

In the picture below showing the spectrum of grinds in a SR, the sharpening angle of your bevel/edge is going to be the same. So what differences does it make in use? Is it just about the weight of the blade, or are there other things? Do people have a general preference for how hollow they like, or do you to mix it up?

Also - does a 'full wedge' still have some concavity to the grind? Or does the bevel extend all the way to the spine, so you'd be sharpening it with the whole side of the blade touching the stone?

 

[Legion]

The difference in shaving comes down to feedback and feel. A heavier grind cuts the hair with less noise and vibration than a hollow. Some people prefer one over the other, or something in the middle.

A true wedge has flat sides (or very close to). So unless you are using tape, there is a big contact patch on the hone.

That was the main selling point of the hollow grind, back in the day. They are generally easier to hone.

 

[Gamma]

Some 'true' wedges are a little convex. Some have a miniscule hollow that is probably the result of being made by hand and not by outright design.
I have to assume 'full' wedges were intended to be honed with the 'spine' up off the stone. Almost every one I've had that wasn't worked on by a 'honemeister' showed zero or super minimal signs of having been 'on' the stone.

 

[azwetshaver]

As mentioned, the heavier grinds lack feedback. When they have a great edge, these razors seems to wipe off the whiskers. I also feel the difference in weight similar to the difference in an aluminum DE and a stainless steel DE.

Full hollow or heavier grinds are mostly personal preference. Those with thick beards tend to enjoy heavier grinds.

 

[Legion]

Some 'true' wedges are a little convex. Some have a miniscule hollow that is probably the result of being made by hand and not by outright design.
I have to assume 'full' wedges were intended to be honed with the 'spine' up off the stone. Almost every one I've had that wasn't worked on by a 'honemeister' showed zero or super minimal signs of having been 'on' the stone.

This has always been my assumption. Honed like a knife, with the spine just a tiny bit off the hone.

 

[HazMat Shaver]

I dont think a full wedge could be a razor. I could be wrong. I slways thought in those diagrams they show a full wedge just for reference. Id hate to try and hone one of them.

Im more in the middle ground. S like an extreme hollow blade but half is good too.

 

[Darth Scandalous]

It may be technique, but I've never gotten along with any quarter hollows I've tried, and only a couple half hollows. My beard isn't particularly tough except on my chin (and mustache, but I don't shave that). Unfortunately my chin is also quite sensitive. Full hollows seem to be best for me although I get along well with my framebacks, which while relatively thin, are pretty stiff.

 

[global_dev]

Anecdotally, i feel like the razors that often feel like i am more going to get a kiss from the edge are the flexible super hollows. Dont know why or if its even true, just feel that they do. Maybe its the way i hone them compared to the 1/2 and quarters.

 

[cotedupy]

This has always been my assumption. Honed like a knife, with the spine just a tiny bit off the hone.

Thinking aloud here...

If one did have a completely flat-sided true wedge SR, then the best way to sharpen it should theoretically be with the entire bevel flat against the stone (I would have thought). In the way that you sharpen the wide bevel on a single-bevel knife.

If you always sharpened it with the spine slightly raised then you're going at some point need to thin it, as your sharpening angle will continue to increase as you abrade metal over time. Whereas having the full width of the bevel on the stone abrades metal at the spine area and maintains geometry, as with hollow grinds.

The difficulty with that though would be the potential to create quite fragile wire edges, though the edge-leading motions of razor sharpening would help to a large degree. The other things that would obviate that problem would be a kind of 'hamaguri' sharpening involving a small amount more pressure applied at the edge - you could do this just at the end of your honing run. Or simply one or two strokes, again right at the end, with the spine marginally lifted, after doing the large majority flat against the stone. Both of which strike me as far easier than trying to maintain an exact angle for a whole progression while freehand sharpening a razor.

I imagine I'm missing some glaringly obvious reason why you couldn't sharpen a wedge SR like that. But the theory is sound I think.

 

[Gamma]

A wedge or near wedge can be honed 'flat' on the stone, I've done it. it's a difficult experience.
Lotsa 1st hand evidence suggesting wedges were honed off the stone. Almost every one I have owned (many) showed zero stone wear above the bevel.
Agreed that this makes for a steeper angle and less cutting efficiency, but it seems to be how things were done. It is, I believe, one reason why the 'hollow' became standard, although to varying degrees.
Yes, there are 'real' and 'full' wedges out there. They do exist, they are not just a reference on a grind guide. They are, usually, not 'perfect' like the drawing might suggest though. Lotsa waves, miniscule hollows, etc.
And those wedges can be quite a fine razor, although they can be difficult to hone at first, especially if the steel is heavily pitted. Geometry matters - if the angle is stout then it won't cut as easily as one with a more acute angle. 200+ yr old razors have had their geometry changed significantly most of the time.

 

[cotedupy]

A wedge or near wedge can be honed 'flat' on the stone, I've done it. it's a difficult experience.
Lotsa 1st hand evidence suggesting wedges were honed off the stone. Almost every one I have owned (many) showed zero stone wear above the bevel.
Agreed that this makes for a steeper angle and less cutting efficiency, but it seems to be how things were done. It is, I believe, one reason why the 'hollow' became standard, although to varying degrees.
Yes, there are 'real' and 'full' wedges out there. They do exist, they are not just a reference on a grind guide. They are, usually, not 'perfect' like the drawing might suggest though. Lotsa waves, miniscule hollows, etc.
And those wedges can be quite a fine razor, although they can be difficult to hone at first, especially if the steel is heavily pitted. Geometry matters - if the angle is stout then it won't cut as easily as one with a more acute angle. 200+ yr old razors have had their geometry changed significantly most of the time.

Interesting, ta!

Your description of it as 'a difficult experience' made me think... probably something I hadn't taken into account is that when you sharpen a zero-grind single-bevel knife it's almost always going to be clad, whereas a razor is going to be hardened most (all?) the way up. I imagine that probably makes a big a difference.

Good point also re hollows and waves in the grind - I don't think I've ever seen the main bevel of any knife (however posh) without at least one 'low spot' revealed when you put it on stones. But that's less of an issue with san-mai construction than it would be for a razor I suspect. Or at least easier to rectify on jigane.

Pitting though is still a nightmare when trying to restore old yanagi &c. That takes a long time!

 

[johnmrson]

I like them all. They just shave differently. If really pushed I'd probably admit to preferring a stiffer grind. Something like a 1/4 hollow.

 

[2bit_collie]

I only have 2 true wedge razors, both early 1800s Sheffields. Both have relatively narrow angles on the wedge, so even with the edge off the stone, the bevel angle will be in the right range. In one case I honed the razor with 3 layers of tape and still measured the bevel angle at 15 degrees. I can’t even get the edge on my strop unless I lift the spine a touch.