Thread: Is there a coating...

...on these Naniwa stones?

I've been working at honing, but only dulling my razor, when I got the idea in my head that I hadn't lapped my hones enough -- On one of them, the 12k, I figure I did lap it sufficiently -- after which the even coloured surface gave way to a speckled consistency underneath. That stone didn't seem to do any damage. It's when I went back to the 8k that things got worse.

I hadn't assumed that all the stones are the same as the 12k -- with the speckled consistency, but after slaving at the kitchen sink for half an hour last night (a woman's work is never done... [don't quote me on that]), I found the same thing on my 5k stone. There's a speckled consistency beneath the even colour that seems to come off (with much effort) in a fine silt that gums up the DMT.

Hopefully I've described this well enough. Does this sound right to everyone?

Thanks

Brenton

I'm not sure if we're talking about the same thing but mine have speckles so I guess it must be the same ? Seems to me that is a normal state of affairs. When I lap any stone I draw a pencil grid and lap under running water in the kitchen sink so the swarf ,,,of silt as you call it runs off. Sounds normal to me.

pics please.
If I understand what you are talking about , the Superstones are resin bound abrasive, I think that gives the speckle like appearance?

My Naniwas also have a speckled look to them.

The speckles are not evenly distributed.

Ok, I think I'm beginning to bark up the right tree.

I'd touched up my razor with the assistance of a local honemeister on the 12K, but after I shaved with it, I thought I'd try to do some more touching up at home. When I went down to the 8k stone, which I hadn't lapped down to the speckle finish, I made the razor dull. I thought I was careful. So, then I went down to the 5k, and only made it worse.

So, the way I figure it, this coating on the stones is probably not abrasive, so gives no sharpening benefit, but is also soft, so the edge is perhaps digging in and or folding back on itself.

If this sounds right, well, I just have a lot more "woman's work" to do over the kitchen sink, lapping the crap off my 8 and 5k hones.

Phew. This feels like relief is insight for me. I was getting pretty frustrated that my careful, though inexperienced honing was doing nothing at all to help.

What a helpful lot you fellows are. Many thanks.

Brenton

IME I drew a pencil grid on my Naniwa stones and lapped that grid off. No more no less. Once flat the stones performed just fine. I don't see the need to lap them beyond that. I would perhaps look to your stroke, pressure ..... honing technique before I found fault with the hones.

When I first lapped my Naniwa 8k/3k stone it produced a slurry alarmingly fast. It felt just like chalk so I was afraid to lap it too much. For this reason I only lapped it flat.

As for the coating on the stone, I have found that I can get the blade to pop hairs off the 1k, but then when I go to the 3k it dulls again. For some reason I can't get the 3k side to make the razor pop hairs. Giving up in frustration I go to the 8k and in not many strokes it easily pops hairs. So I am starting to think that when the hone is made there is a surface which forms on top which needs to be lapped off.

Thanks for your feedback guys.

I thought I had cracked the mystery with lapping off the coating on the hone, so with much elbow grease, I got the 5k down to it's speckled finish (removing the sludgy goop that seemed to coat its surface), then made it flat.

Then lapped it 5 times, 10 times, 20 times, 50 times.

It won't pop hair, but if I hold a few leg hairs firmly at the end, I can saw through it.

We may be back to technique here, though I tried to be oh so careful.

It seems something of a black art to me. I'll keep trying. Mean time I have a USB microscope coming.

I think maybe we are having a semantics problem here....


The Naniwa's are a pain in the butt the lap the first time out...

Here is what seems to work lap, lap, lap, hone, lap, hone, lap, THEY ARE READY !!!!

When we say "lap the hone" we usually mean draw a pencil grid on the top of the stone and rub that off with a lapping stone... ONCE

If you are using a DMT you have to do this in the sink with running water on the stones or they will gum up and wipe the pencil off the stone before you are done...

Lap all the stones hone a razor, lap again, hone a razor, lap again.. this is when the stones start to act right...

The Naniwa's can deceive you on the normal sharp tests from 3k-10k They act pretty much normal at the 1k level and at 10k and above.. But starting at 3k they can fail the tests that you have grown used to on other stones.. They are just really smooth and the edges don't have that toothy sharp feel... Just hone through this and keep going one time, and see if you are actually on the right track, go though the finishing on 10k or 12k and just try a test shave.. First few times I used them I thought the same thing, until I finally honed through and found an incredibly smooth shave at the end...

Mine has a speckly appearance, too. It also goes out of true quite quickly for a fine grade stone, so I am forced to believe that the resin matrix is not that dimensionally stable. I lap all my stones with a DMT during use, about once a week or more. Once every 3 or 4 weeks I use the grid test along with wet and dry paper on a thick plate of glass. The naniwa always has hollows and humps in areas that you wouldn't expect, and always behave much better after proper flattening.

IME Glen is right about the smoothness of the edge contributing to the "hair popping" - the relatively ragged edge straight off a 1k stone always pops hairs for me, then the increasing smoothness of the edge with each succesive stone grabs the hair less and less.

I reckon you will easily see how each higher grit stone removes the marks from the stone before it when you get your scope.

Regards,
Neil.