Thread: Line on Nakayama... Fix, or Ignore?

Forgive me if I am asking a silly question, but I have used synths up until about a month and a half ago, so I am still learning the world of JNats.

A couple of weeks back, I got a Nakayama Asagi Namito off etsy. I tried it on a couple of razors, and it created slurry very quickly, cut fast, and seemed to do a good job off the 1K to polish with a nagura progression to water.

But after that initial honing session with it, after lapping it flat again, I could feel a "line" coming down the stone diagonally. In bright light, I can actually see (though barely, and its quite thin) the line running almost the entire length of the stone, starting near one corner, making a sort of soft C shape out into the middle of the stone, and back down to the bottom where it vanishes. Repeated lapping with a DMT 8 (325 grit) got rid of a lot of the feel of the line, but there still seems to be a bit in the middle of the stone where it cuts out from the side in that "soft C" I mentioned.

I can still SEE the line under bright light, but that doesnt concern me much. The concern is the parts were I can feel it. If I can feel it, my blades will be able to feel it, and cause whatever damage it may.

So, as a newbie to JNats, should I be right to be concerned? And if so, should I just keep at it with the DMT? Or is there a better method to deal with this?

If it makes any difference, here is the line in the stone magnified to about 50x at a place where I can feel it:


And the stone showing where the line goes:



Thanks!

Does it affect the edge, how are the shaves?

It is a natural stone, and may have some inclusions or a hair line crack. Not all inclusions or cracks, will affect the stones ability to hone.

Does not look toxic. But proof of the pudding is in the honing. Does it feel scratchy when the razor glides over it? Does it leave deep striae on the cutting edge? If not: no worries.

I have been too afraid to hone anything on it since I discovered it!

Looks like I need to give it a run.

If it causes issues, I suppose I could get out the chisel and make some tomos out of it!

Thanks, guys! I will run a razor over it and see what happens.

It’s not like it will ruin your razor, possibly a small chip.

If you have honed on it already and did not feel it or have an issue, you are probably good.

You would have felt it if it was going to be a problem.

I have not done this but have read how some have cleaned toxic lines from stones.

You mention that at first it worked fine but then after lapping it got worse. Maybe the previous owner cleaned it and when you lapped it you brought it again to the surface?

Again I have not done this but it makes sense to me like with a strop that has been cut you can trim and smooth it to be not noticeable.

Get a fiberglass pen or a thin diamond coated dremel tool and you can scrape it out. Not to hard to do.

So, pulled out an FWE Special my dad's girlfriend gave me back in Feb for my birthday... dull as dishwater, so I ran it over the 1K, and then to the Nakayama in question with a yae-botan. The razor wasnt catching on the line, and the 1K striations were gone, with no oddities. I ran the FWE over the Nakayama with water only to see if that would make a difference... it didnt. I did not feel the blade catch on anything, and with a 40X loop, looked normal (with the yae-botan's striations, of course).

So I guess I freaked out over nothing. Odd that my finger can feel the line, but it doesnt effect the honing. Whatever... I know it's fine, and that is what counts.

Thanks for your suggestions, gents! I appreciate it, as I am going though this new JNat journey!

Originally Posted by Aldwyn

So I guess I freaked out over nothing. Odd that my finger can feel the line, but it doesnt effect the honing. Whatever... I know it's fine, and that is what counts.

Thanks for your suggestions, gents! I appreciate it, as I am going though this new JNat journey!

It must be an inclusion hard enough to feel by touch but too soft to have an effect on steel. Or it might be a hollow inclusion rather than a bump, possibly because it's softer than the rest of the hone and wore faster with lapping.

Good news, because inclusions suck, even though lines are generally fixable; unlike particle inclusions.

Regards,
Pieter