Thread: Harshness and Final Bevel Shape

Originally Posted by JimmyHAD

So the question becomes, is the criticism of the arched bevel, from whichever source created it, justified ?

Not in my opinion. I did some experiments with pasted hangers and a slightly arched bevel is no problem as long as the final angle stays in a normalish range. I believe one of the members here kept a journal in a thread of his multi-month-long experiment using a pasted strop, and noticed no degradation or dulling over that period.

But then neither is the praise heaped on the multi-bevel technique justified. This is a fine way to reduce the time spent on your finishing hone - this is after all why the commercial razor blade manufacturers use multiple bevels. But the resulting edge isn't any better or worse than you get using a single bevel.

Just for giggles, I sharpened a Maher and Grosh up last night totally on BBW and Coti. After much diluting and finally a polish I looked(100x) at my work. all done with no tape, the far edge end of the bevel looked very shiny as if it had a micro bevel. Hmmmmmm
Just an observation...

Was it a clean transition to shiny or a gradual one? What was the grind on the M&G?

Originally Posted by Kingfish

Just for giggles, I sharpened a Maher and Grosh up last night totally on BBW and Coti. After much diluting and finally a polish I looked(100x) at my work. all done with no tape, the far edge end of the bevel looked very shiny as if it had a micro bevel. Hmmmmmm
Just an observation...

strop and see if its gone. Those continuous, sometimes less so, streaks of light at the extreme edge I have assumed to be a bur. my scope is likely not near as good as yours. I figure the light I am seeing is a good bit larger than the object actually reflecting it .The shines that I have seen disappear after a stropping.

Originally Posted by Kingfish

Also, supporting the importance of having some degree of convex shape are some of the best razor honers using diamond spray on felt to finish off their bevels. Some of the naturals may also be creating a degree of convex bevel do to their slurries.
It now makes some sense to me that a perfect edge with no convex shape interacts with the skin giving a harsh shave. A convex shape, by whatever means created, makes contact with the skin at the same time as the edge supporting it and giving a smooth shave. Does that make sense?

My last word on this just to restate, microbevels were not even the main point of the post. Very few people can create a perfectly flat bevel on a flat hone even if they wanted to. Here are some reasons why:
1. Slurries pile up in front of blade, create convex shape.
2. Nervous system and skeletal system do not move in perfect lines, meaning that sometimes there is more pressure on the hone than others causing flex in blade, create convex shape.
3. Softer stones by their very nature give and release abrasives quickly, create convex shape.
4. Small imperfections on the surface of the hone contact leading edge first making it wear faster than behind, create convex shape.

If all the above factors are not valid, then my knowledge of sharpening is very flawed.(it could be)

Other factors that honers indulge in frequently also create convex shapes after razor is honed by stropping. Please, for me this is all in good fun, I made an observation, reported it and still am not trying to draw an elaborate conclusion, and if it came off that way, shame on me.
Mike

Last word; ohhh. Never
Matte Surface Mystery « The Sharpening Blog

be sure to continue on to part 2.

Originally Posted by Kingfish

Some of the naturals may also be creating a degree of convex bevel do to their slurries.

So if I can shave comfortably off my Asagi finishing with only water & palm stropping, say 10x afterwards, how much convexity we talking here ?
Surely not the same as a layer of tape.

Originally Posted by kevint

Last word; ohhh. Never
Matte Surface Mystery « The Sharpening Blog

be sure to continue on to part 2.

Interesting read. So Harellson told Ron Hock that, “the very best natural waterstones top out at about 10,000 to 12,000 grit”. I am surprised at that having heard so much about the fabled J-nats going well beyond even the Shapton 30k. Of course that is only one man's opinion.

Edit, Kevin, I had to work to find part 2 here but glad I did. The natural edge looks 'better' to me at 3,000x. I wonder how the one will hold up as opposed to the other ?

Originally Posted by JimmyHAD

Interesting read. So Harellson told Ron Hock that, “the very best natural waterstones top out at about 10,000 to 12,000 grit”. I am surprised at that having heard so much about the fabled J-nats going well beyond even the Shapton 30k. Of course that is only one man's opinion.

Edit, Kevin, I had to work to find part 2 here but glad I did. The natural edge looks 'better' to me at 3,000x. I wonder how the one will hold up as opposed to the other ?

Are the stones used for woodworking tools the same as the stones used for razors? I am not convinced that a chisel needs to be finished on a razor quality stone to do its job properly, may be I am wrong

Originally Posted by mainaman

Are the stones used for woodworking tools the same as the stones used for razors? I am not convinced that a chisel needs to be finished on a razor quality stone to do its job properly, may be I am wrong

I know no more than you on the woodworking but the synthetic stones that we use to hone our razors, Shaptons, Nortons, Naniwas etcetera are made for woodworkers. We have adapted them to our pursuit and since steel is basically steel they work well..... IMO.