Question about break-in time/load up/polishing abilities on Shapton #16000

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I just received a Shapton Glass #16000 yesterday, mainly for the purpose of finishing the sides on certain knives, after thinning, before stropping. My main question is roughly how much time should I need to spend on this stone to get it to the point to where it's broken in? I was using it to finish up a thinning on my cheap 8" VG-10 chef's knife, which was purchased for the sole purpose of practicing & experimenting with various knife maintenance techniques. It began to load up as soon as I started using it to finish up thinning of the secondary bevel(the first picture of the load up is not as extreme as it had initially occurred, I just did a quick few strokes to give an example). I also own a Kitayama #8000, and it too behaved very similarly when it was new. It took about a half dozen sharpenings to get to the point where it wouldn't immediately load up. The load up on the SG #16000 is also similar to the nature of the load up I experienced on my K-#8000, as it acted like there was something sticky on the blade such as tape adhesive, which after loading up, would have a tendency to begin to ball up & roll around under the blade edge. The load up on the SG #16000 came off very easily after gently rubbing the a medium grit nagura over it, and after that, the load up built up to a slower degree(only when I left the nagura slurry on). I never seriously expected to be able to get a mirror finish on the secondary bevel on the knife in the lower picture(which I photographed at an angle to show the scratching as much as possible), but had hoped to be able to do a little better than the results above. So my second question is, after the SG #16000 is broke in, will it be a better polisher, or remain just as aggressive as now? Thank you in advance for any, and all replies.
 
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Does water puddle or bead on it? All my Shapton's except the 120 Pro needed a light lapping out of the box. They have a thin outside layer that's not quite like the rest of the stone. Almost waxy.

P.S. Shapton's aren't generally known for polishing.
 
Does water puddle or bead on it? All my Shapton's except the 120 Pro needed a light lapping out of the box. They have a thin outside layer that's not quite like the rest of the stone. Almost waxy.

P.S. Shapton's aren't generally known for polishing.
Thank you very much for the reply, I appreciate it. Yes, at first it strictly beaded up, until after a few passes. After removing the load up with the nagura each time, the beading became less & less, and eventually there was very little beading, and just a very thin layer of water. Yes, my current understanding is that SG stones are primarily cutters & not polishers, I had just hoped in the beck of my mind for slightly better results. However, for my main purpose I will be using it for, it's far more useful as a cutting stone, than a polishing stone.
 
Wait, you're using a 16000 grit stone to try to clean up the wide bevel on the knife pictured above? I'd never use a stone that fine for polishing (or really for anything), but even if you were to do so, you'll be polishing forever if you're going to try to take out those big scratches on the blade above. Start with a much lower grit. It depends very much on the stone, but most of my polishing tops out around 3k. Others may take it higher, but only after spending a significant amount of time at lower grits.
 
Wait, you're using a 16000 grit stone to try to clean up the wide bevel on the knife pictured above? I'd never use a stone that fine for polishing, period, but even if you were to do so, you'll be polishing forever if you're going to try to take out those big scratches on the blade above. Start with a much lower grit. It depends very much on the stone, but most of my polishing tops out around 3k. Others may take it higher, but only after spending a significant amount of time at lower grits.
Thank you for the reply, and I mostly agree, that knife is getting a total makeover ATM, I thinned it way out, and I'm starting at a lower grit when I get to working the edge. I'm doing a lot of experimenting right now, just trying out new things. Also, I don't use higher grit stones like 5-8k for just polishing, I actually sharpen with them, and go until I get a very light, even burr across the entire edge, deburr it, then finish by stropping. I'm sure it sounds crazy to most people, but I'm actually getting the results I like. Polishing the secondary bevel serves for no other purpose than looks, and I'm sure if I ever get polished up to where I want it, it will likely stick like crazy, but again, this knife is for experimenting.
 
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You mentioned that you were getting something sticky on the blade. I noticed that too on my cheap knives. Maybe because of the stainless? That's my best guess. Mine is sort of a gummy paste that sticks to the edge and mostly at the tip of the knife and I have a bit of a trouble removing the paste by hand unless I use tissue paper to wipe it away. It's as if the paste is "magnetized" to the edge/tip. Here's a photo.
 

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Those scratches on the blade face aren't from the 16k. They're from a stone earlier in your progression that wasn't taken out with successive grits
 
You mentioned that you were getting something sticky on the blade. I noticed that too on my cheap knives. Maybe because of the stainless? That's my best guess. Mine is sort of a gummy paste that sticks to the edge and mostly at the tip of the knife and I have a bit of a trouble removing the paste by hand unless I use tissue paper to wipe it away. It's as if the paste is "magnetized" to the edge/tip. Here's a photo.
Your knife is magnetized.
 
You mentioned that you were getting something sticky on the blade. I noticed that too on my cheap knives. Maybe because of the stainless? That's my best guess. Mine is sort of a gummy paste that sticks to the edge and mostly at the tip of the knife and I have a bit of a trouble removing the paste by hand unless I use tissue paper to wipe it away. It's as if the paste is "magnetized" to the edge/tip. Here's a photo.
Thank you for the reply, I think we have the same problem.
 
Those scratches on the blade face aren't from the 16k. They're from a stone earlier in your progression that wasn't taken out with successive grits
Thank you for the replies, I'm sorry I wasn't more clear in the first place, but I haven't touched the edge itself yet with the SG 16000, I was referring to the sides of the knife, just behind the edge only, after a partial thinning. I thought I could thin it down further than I was able to with a Suehiro #320, but it just has too much metal above the edge. How would a knife get magnetized? The knife has a very large apex bevel because I only started working with stones a month ago, was using it to practice on, was having trouble holding it steady, & getting a consistent bevel on the edge.
 
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Your knife is magnetized.

That may be the case. However, I don't use a magnetic rack nor have I used the knife near any magnets. So I was wondering why it happens. I'll look for a way to demagnetize it. I don't experience the gummy residue on my carbon knives. I've also tried sharpening an AUS-8 one but it doesn't load up like that. No idea as to what steel the cheap one in the picture is. Thanks, either way!
 
With other makers, from to time you get a stone with some inactive crust: doesn't do much, does not take any water. With Shapton Glass, I got the impression that's the case with every stone. Must have to do with the production process. So: first lapping, with a diamond plate, or a coarse stone and lukewarm water. Once the outer layer removed, the abrasive particles are freed.
 
An accumulation of swarf, the mix of stone slurry and metal particles, behind the edge is perfectly normal and indicates that the very edge hasn't yet been reached. A marker and a loupe (8-10x) will confirm. Heel and tip areas are favourite locations. Don't let it dry.
 
Polishing is all about removing the scratch marks from the previous grit. 16000 is very fine and slow! What is your progression for this thinning/polishing? If it were me. I would make small jumps in grit, no more than 2x. Also, mark the surface with a sharpie to make sure you are getting all the spots. Change direction with each stone change so you can see when the previous scratches are gone.
 
Polishing is all about removing the scratch marks from the previous grit. 16000 is very fine and slow! What is your progression for this thinning/polishing? If it were me. I would make small jumps in grit, no more than 2x. Also, mark the surface with a sharpie to make sure you are getting all the spots. Change direction with each stone change so you can see when the previous scratches are gone.

Thank you very much for your reply, and for taking the time to better explain the process, I appreciate it. Here is the stone progression I followed, and I actually spent at least what I thought was an adequate amount of time on each subsequent stone, as well as diversifying the angle as I went on each stone:
Suehiro Cerax #320
Suehiro Cerax #1000
Chosera #3000
Suehiro Rika #5000
Kitayama #8000
Shapton Glass #16000
The knife was really thick behind the edge and up to the shinogi line, and the #320 just wasn't enough to get it adequately thinned out, so I went I far as I could until I got fatigued, took a rest, then finished the progression. Things were looking fairly positive up until the SG 16000, and then at that point the stone just loaded up right away, and never really improved the surface(it actually made it worse). I honestly never expected the SG 16000 to get a fine polish, as from what I've heard, SG's are mainly solid cutting stones. ATM I'm working on the apex bevel, and I'm beginning to suspect the knife itself may be a big part of the problem, as I'm getting more than usual load up on my Kitayama #8000, after working up from the Chosera #3000. This knife has never loaded up this bad on the Kitayama before, so I don't really know what's going on right now. I only started working with stones a month ago, so I've still got a lot to learn. Back in the day I was using a Tormek on German steel, and that's what I was accustomed before switching to J-knives & stones.
 
Hi,

I dont know if theres anything wrong with your shapton. But i can tell you easily that there's lots of wrong with your sharpening, and until you fix it, you will not get the results you want, no matter which stones you use.

Forget about the high grit stones, go back to the 1k and learn how to use it. There is no advantage at this point in using such high grit stones for sharpening. Just by looking at how uneven your bevel is, i can tell that you are just going to blunt your knives with your high grit stones.

As for polishing...... That takes a little more skill than regular sharpening. but i would tell you the same, forget about your higher grits, you are not doing the work needed on your lower grits, so everything else done in the higher ones is a waste of time.

There's no magical stone that can make up for lack of skill.
 
Thank you very much for your reply, and for taking the time to better explain the process, I appreciate it. Here is the stone progression I followed, and I actually spent at least what I thought was an adequate amount of time on each subsequent stone, as well as diversifying the angle as I went on each stone:
Suehiro Cerax #320
Suehiro Cerax #1000
Chosera #3000
Suehiro Rika #5000
Kitayama #8000
Shapton Glass #16000
The knife was really thick behind the edge and up to the shinogi line, and the #320 just wasn't enough to get it adequately thinned out, so I went I far as I could until I got fatigued, took a rest, then finished the progression. Things were looking fairly positive up until the SG 16000, and then at that point the stone just loaded up right away, and never really improved the surface(it actually made it worse). I honestly never expected the SG 16000 to get a fine polish, as from what I've heard, SG's are mainly solid cutting stones. ATM I'm working on the apex bevel, and I'm beginning to suspect the knife itself may be a big part of the problem, as I'm getting more than usual load up on my Kitayama #8000, after working up from the Chosera #3000. This knife has never loaded up this bad on the Kitayama before, so I don't really know what's going on right now. I only started working with stones a month ago, so I've still got a lot to learn. Back in the day I was using a Tormek on German steel, and that's what I was accustomed before switching to J-knives & stones.
Like I said before, the 16k didn't make the surface worse. It's just highlighting the poor job you did on the previous grits.
 
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