Thread: the correlation between stone's surface polishing degree and the honing it offers

I use one of my phig's to lap most of my stones. Leaves them nice and smooth.

Originally Posted by Vasilis

Do you use the stone without the 0.5μm diamond slurry? If yes, do you think it's finer than before? I usually lap my C12k with 600 grit diamond plate, and regardless how fine it gets after with honing, I don't see noticeable difference.

i used it before with plain water... i tried it with the little slurry stone but it always seemed to leave debris that a. scratched the stone... or b. assed up the edge of the razor.....

now i will make ~20ish passes with water... then i put 3 or 4 drops of the diamond slurry and make ~50-100 passes or till the edge looks polished sufficiently... i honestly believe the diamond slurry is the reason the stone looks so polished now..... i was looking at it a minute ago and you can see a very good reflection in it....

I used the C12k with a C12k slurry stone, with or without slurry it still gives a polished marvel like reflection. But it becomes even slower.

Just some points to ponder, any media with use will get polished and shiny. A strop will develop a shine over use but I don't think that affects the job it does. In theory a rock has a certain hardness and whether it is polished or not will not change that hardness. I know with my hones I lap them to a shine and they work better in the sense that they seem to almost have a lubed surface but I have never noticed them to work differently as in a better edge whether they are polished or not. Now when I say polished as opposed to not polished I don't mean a hone that comes from the factory with a really rough surface I mean a good working surface and a truly polished one.

Originally Posted by thebigspendur

Just some points to ponder, any media with use will get polished and shiny. A strop will develop a shine over use but I don't think that affects the job it does. In theory a rock has a certain hardness and whether it is polished or not will not change that hardness. I know with my hones I lap them to a shine and they work better in the sense that they seem to almost have a lubed surface but I have never noticed them to work differently as in a better edge whether they are polished or not. Now when I say polished as opposed to not polished I don't mean a hone that comes from the factory with a really rough surface I mean a good working surface and a truly polished one.

but a polished surface is much less abrasive.... therefore... as the stone becomes shinier it slows its cutting and is able to polish the steel leaving less scratches.....

There's more to it than the surface. The abrasive grit is usually suspended in a media, and it is how easily this media releases the abrasive particles, and what those particles do when released, that determines things like cutting speed and polishing ability. Sure, if you are talking about a tightly bound grit, then surface texture can play a role, but in my experience most stones release grit into the water.

James.

I've given this some thought in the realm of eschers particularly. I've always used a 325 diamond plate to lap all of my hones. Actually on some real tough synthetics I've also used a DMTXX which ,IIRC, is 120 but I always finish up with the 325. I have one honing friend and mentor, Randy, who likes to lap to 1k with wet and dry sandpaper. Speaking of finishers, I don't recall if he does so with a 4k/8k. TBH I'm just too lazy to go to that extreme. Oddly enough I know another really good razor honer who likes a rough surface on his hones and prefers a Norton lapping plate from the old days. I'm told they were rougher than the current one.

I asked Lynn and Tim Zowada if they used slurry on their eschers. They both said no. Tim said he didn't see any point in dragging his edge "through mud." He added a smiley when he said it BTW. I, OTOH, do like to use a slurry on my eschers. The escher label has instructions on it which specify using the rubbing stone to create a 'lather' and that is why I kept with it. I do dilute as I go and I seem to get better results that way. Not better than if Lynn or Tim honed it, but better when I hone with slurry than with out it.

I prefer the feedback (or lack thereof) of a glassy smooth surface. I get that from lapping with a softer stone.
IME it doesn't make a difference to the cutting ability.

From the photos I have seen under a microscope for the escher stone specifically, the polishing it offers doesn't change weather it's used with or without slurry. From what I know, a stone without slurry gives a finer finish, so, it's use depends on how dull a razor is.
The way I'm thinking, about the polishing degree the surface of a stone has is, when the stone is been lapped with a low grit sandpaper or lapping stone, the surface of the stone appears to have "mountains and valleys" in a micro-scale. For the softer stones, I imagine that it doesn't really worsen their polishing abilities, but for the harder ones like novaculite, where quartz particles are bonded together by quartz, this type of surface might act as a different grit stone, scratching the steel. From my experience, the coarser I leave my hones (around 600grit) the faster they are. The glassy surface seems to work slower, but minimizes the chance of a scratch.
I'm not sure, Llyn Idwal and Charnley forest stones are a slate type of stone or novaculite? I have the impression they re the later.

I've used an Escher for years. For the longest time, I used it with just water, I have a few, and I did rub two of them together to create a slurry. I remember not being too impressed with the results. A few of my Escher's have instructions, some say use water to create a "Slime" and others say to use a rubbing stone. Now, the y/g I use now does benefit from a slurry. I use it, and make two dilutions, the last lap is plain water, and I always get great results. It's never disappointed me. Kind of my go to hone. Short of bevel setting, it's all I use these days.

Stones can glaze over causing a shiny surface and imparing your results. I had a J nat, a Nakayama Maruichi Asagi. (I think it has a few other titles, can't remember) oh yeah, "Nihon Kamisori" I think...TBH, these J nats drive me crazy. Anyway, it's surface had become glazed, A good lapping was all it needed to become a good finisher again. Now, I don't think that's what the op is talking about. I have a few stones w/ shiny surfaces that do fine the way they are. YMMV.