Just got a 16K Shapton hone which is leaving stria on a polished 12K. What am I missing here?
Bob
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Just got a 16K Shapton hone which is leaving stria on a polished 12K. What am I missing here?
Bob
Bummer Bob! I wouldnt think that would happen.
Lap it some
Had the same with mine
Will do.Quote:
Originally Posted by rolodave
Bob
I had the same issue with 2 16K Shapton Glass stones - lapping didn't help and I was concerned enough at the time (a few years ago) to contact Hap Stanley who at the time was head of Shapton USA. He gave me a few suggestions but none really resolved how the scratch pattern looked under a microscope. If you compare the scratch pattern between an 8k Shapton glass and a 16K there's a markable difference. After going round and round with this Hap suggested he would take it to the factory and see if there had been any issues with the binder they were using on the 16k. I do not know what ever happened with that and Hap has since broken his ties with Shapton.
At that time I was into synthetics and ultimately solved the problem by purchasing a Suehiro 20K - no such issues with that stone. I've since abandoned high grit synthetics in favor of naturals.
I hope that you'll post your results - I'm interested in what others find. As an aside this is not an uncommon problem with the 16K - I've heard of several folks with the same issue.....
Good luck
I know it must be disconcerting to find ugly stria after using the 16K, but the real question is “how did it shave?”
Here’s a quote from Keith Johnson on scratch patterns left by a Vermio hone that might be appropriate here:
The scratch pattern off the Greek stone appear to be similar to what I get from a high-end 8k, or a regular 10k synthetic JIS. I have seen notably finer striations from other slates - my Ark, and Eschers. That is not indicative of much but it’s something to think about. Lunes leave the ugliest scratches, they’re horrible to look at actually, and the edges from those stones can be ridiculously keen. Coticules too – ugliest damn bevels but they can still be super smooth as well as very keen. So I don’t put much stock into striations and how they look most of the time.
For me, the shave was underwhelming which is what led to looking at it under the scope
I did not need a microscope to see the stria, just a 10X loupe. The disconcerting part was not seeing stria but how they looked like they came from a lower grit Naniwa hone. I took Dave's advice and lapped the Shapton 16K and took it to the edge again. Still stria there but really civilised ones. I then gave the blade a good stropping on a Crox sprayed felt hanging strop, 40 or so strokes plus the usual linen and leather. The shave was perfectly fine and possibly a bit keener than the 12K Naniwa followed by the Croxed felt strop.Quote:
Originally Posted by DZEC
Like your quoted section, I normally don't put much stock in how the bevel looks. I have found that, on more than one occasion, after a good shave a quick look at the edge with a loupe showed something I hardly would have expected a good shave from. Sometimes we worry too much.
I think I will play with the Shapton some more though. I will say that the Shapton 16K removes metal fast and Dave may be right that you could do the whole job from bevel reset to finish with it.
Bob
I do remember when my 16k was new that it had a gritty feeling and was leaving deep scratches.
Time passed and I learnt to hone and lap. It is fine now..
They have that "skin" on them that has to go. For their price, you would think it would be silky smooth. You get it properly lapped and you will be fine. I've been a shapton guy for most of my honing experience as no other stone is as efficient. If you wish, I could send you mine as a reference. I typically use mine as a "barber stone", when a razor starts to feel off.
Thank you very much for your generous offer but I think after lapping my hone we are starting to see some potential. I'll just carry on with it. Yes, you would think at the price they want for those hones they'd be silky smooth and flatter than pee on a plate but they aren't in either respect.Quote:
Originally Posted by ScottGoodman
Bob
I used either 1K or 1.5K wet/dry to lap mine super smooth. Never saw stria like you are describing. Never needed many laps following a thuringian or coticule to get incredibly sharp edges.
My 16K will also produce those coarser looking stria, especially noticeable after the mirror polish left by the 10K. I've only used the DGLP on it. Definitely removes metal quickly.
I just bought a 16k. Mine too is leaving deeper stria, especially noticeable on back of a chisel. In use for wood I notice just a slight less amount of sharp compared to the dmt 1micron diamond paste I normally use. For shaving the edge is not as comfortable as my naniwa 12k but could be due to my inexperience with the hone or the fact that I’ve only had a chance to do one blade on it. It definitely makes a straight sharp and the shave I got may not of been the most comfortable but it wasn’t unpleasant. Post shave my skin felt good, which is saying something as I have fairly sensitive skin. This hone will live in my woodworking kit but will definitely come inside for the occasional razor. It cuts fast in spite of its grit rating and the feed back for both ww tools and razors I find quite satisfying.
Shapton doesn't recommend using the glass 16k on razors or chisels. They recommend it for knives and scissors. The 16k has a less dense particle distribution than the 10k and therefore leaves a chippier edge than the 10k. Shapton recommends going from 10k to 30k for razors
Yes, and exactly why new users of the 16K Glass Shapton are surprised at the size stria it leaves and a slightly harsh shave that produces. It is really noticeable for me coming from a 12K Naniwa finisher. A toothy edge may be good on knives/scissors but not so much on razors/chisels.Quote:
Originally Posted by criswilson10
Bob