Thread: Japanese Razor Profiles

Originally Posted by kevint

Sort of as precaution against shorting any on the wire edge. vs. (true one sided sharpening) I think there is still a reason for having a small microbevel on the ura.

please explain further...
touching the flat at all is a no-no in Japan on ikebana hasami, but we do it here anyway. we drill rivets, back bevel, micro-bevel, etc all in the name of edge endurance, (don't let that get out). could simply be that our steel isn't what swedish steel or tamahagane is so we need these mechanations.

you chisel guys get to do whatever you please though, so if anyone can give sound justification for beveling the ura it must be a chisel guy. please elaborate.

Is that based on the traditional beveled Japanese razors?
Thanks,
Rick

Originally Posted by OLD_SCHOOL

I beg to differ here. Japanese razors are made at a certain angle, and once you screw that angle up with improper honing that's it. You can't fix lost metal with more honing, you'd need to find a way to add new metal.

Originally Posted by CraigJ

OTOH I am just a gaijin that uses both the concave and wedge side of the blade against my face when I shave. The wedge side gives me a very nice shave I just have to drasticaly change the angle of the razor.

Isn't the "wedge" side what is used to shave with?

Originally Posted by tracr

please explain further...
touching the flat at all is a no-no in Japan on ikebana hasami, but we do it here anyway. we drill rivets, back bevel, micro-bevel, etc all in the name of edge endurance, (don't let that get out). could simply be that our steel isn't what swedish steel or tamahagane is so we need these mechanations.

you chisel guys get to do whatever you please though, so if anyone can give sound justification for beveling the ura it must be a chisel guy. please elaborate.

The reason, I think, is as I said: The ura is not ground true- the few I have are all ground very nicely, but it is still a rough grind. A chisel, kogatana, plane(all single bevel instruments) backs are rough ground at first but the user polishes the ura to flat, finish grit polish, then hones the other side; only touching the back on the finish stone to remove the bur. basic sharpening right?

Both aspects are important to ultimate sharpness and a strong edge: flat and fine polish. The only way to get that on the wa is to hone a microbevel on the ura.

And since it must be there, honing to a true precepticle bur with the omote on the stone is not as necessary as when doing true one sided sharpening. Thinking: I will cut past where the bur would be by doing several strokes. (probably a justification for being lazy) But once it is there all you may need is a single pass ( I do several for the reason above )to clean up until it becomes honed away -then refresh it.

What is hasami, a scissor or type of knife?

Originally Posted by OLD_SCHOOL

I beg to differ here. Japanese razors are made at a certain angle, and once you screw that angle up with improper honing that's it. You can't fix lost metal with more honing, you'd need to find a way to add new metal.

Couldn't you tape one face as needed?

Or the under worked face could be ground down the reestablish the proper proportion of asymmetry. (I don't like that idea either)

I think we are honing in on what a proper shape is by defining the limits of the ura bevel. Does it need be a full 1/3 the size of the main bevel or is only a glint required. What happens if it is 1/2 as wide?

You have had a bunch of them OS what is the most common error found on old abused specimens?

based off of the info that i have gotten here, i took mine to the hones tonight. mine is close to shave ready, so i started on the chinese 12k with a 3/2 pattern. then to .5 micron, then .25 micron, then cro-ox.

i don't use the HHT for anything more than a parlor trick, however i must say armhairs were running away screaming. i may just have to shave in the morning and be late to work.

vgod

Originally Posted by kevint

The reason, I think, is as I said: The ura is not ground true- the few I have are all ground very nicely, but it is still a rough grind. A chisel, kogatana, plane(all single bevel instruments) backs are rough ground at first but the user polishes the ura to flat, finish grit polish, then hones the other side; only touching the back on the finish stone to remove the bur. basic sharpening right?

Both aspects are important to ultimate sharpness and a strong edge: flat and fine polish. The only way to get that on the wa is to hone a microbevel on the ura.

And since it must be there, honing to a true precepticle bur with the omote on the stone is not as necessary as when doing true one sided sharpening. Thinking: I will cut past where the bur would be by doing several strokes. (probably a justification for being lazy) But once it is there all you may need is a single pass ( I do several for the reason above )to clean up until it becomes honed away -then refresh it.

What is hasami, a scissor or type of knife?

thanks kevin. yes, i'm with you. a lot is unnecessary in my view. these are simple, and we should enjoy their ease.

yes, hasami is single-bevel scissor and the same issue exists. it tends to come down to the steel type, with microbevels accepted for poor steel and japanese blue steel, but not for say, japanese white steel, swedish.

I'm a little confused now . Am I to understand from all these posts , that the flat on the convex side gets the honing , and the concave side is only honed 1 or 2 strokes ? I always thought the concave side got the most strokes .

Originally Posted by dave5225

I'm a little confused now . Am I to understand from all these posts , that the flat on the convex side gets the honing , and the concave side is only honed 1 or 2 strokes ? I always thought the concave side got the most strokes .

no, we've been debating how much attention if any, should be devoted to the back of the razor (also called the reverse, or ura) and speaking veery loosely in calling it the "flat". you were fine as you were, honing the concave side which is the front of the razor or "omote".

old school is working up a very nice diagram already (http://straightrazorpalace.com/razor...art-names.html) to make this clear and it is our fault for confusing you. don't be put off if you see only japanese terms in the future, i think the japanese straight users here prefer that everyone stick to the japanese so as to prevent exactly this sort of confusion. apologies~

Let me clarify.

If you have one that is so worn the whole profile is gone then yes the only thing to do is trash the thing. Some of the vintage ones floating around out there have been improperly honed and the blade profile is off a bit and those cases you can bring them back. Now I'm not talking anything drastic here.

it seems to me if you basically hone one side to the exclusion of the other the angle will change over time no different than if you honed a western razor on only one side. You need to hone in the proper ratio to maintain the edge.