why is my water on waterstone dulling my knife?

D

DavidL41

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Oct 12, 2014
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Im sharpening a chisel and when I add water to it the knife edge becomes too smooth almost like I burnished it.

First I want to rule out if its my technique or my blade. The steel is japanese steel and is not of the highest quality. maybe white 2 or yellow steel. I also tend to sharpen only on a 1000 shapton for a long while (5-10 mins). Does the edge start to dull if I sharpen with the same grit too long? Is adding too much water to the stone not good to get that a sharp edge. I find with no water the stone cuts rapidly..

Another notable thing is that the edge does not get a burr ever. Should I assume that it is the steel that is at fault or my technique?
 
Sounds like you have some technique issues, dulling from sharpening too long, not forming a burr, and the typical it's the steels fault. Not mocking you, we have all been their, even me. All these things point at technique and the reality is, it takes lots of practice to get better.

First, it's a waterstone, it needs water to work the right way. Being a splash-n-go stone it will need more water to keep working and letting it run dry will cause loading and burnishing. 5-10 minutes on a 1k not that long depending on the work needed.

Shapton Pro 1k should be fairly coarse and produce an edge equally as coarse with a fair amount of burr. If cutting slowly work up a little slurry by lapping, if the steel is very hard this will sometimes make the difference.
 
Aside from technique, how old are the stones? When was the last time you leveled the stone to be perfectly flat? Wear and tear will cause issues. And it may not even be noticeable at first glance, but an uneven stone will play tricks on an edge.

I use rock polishing grit on thick glass to level. Start with the finest grit and finest stone, work until glass flat. Then add a slightly coarser grit to match the next stone. And so on. I know there are many other options/methods out there, but I use what I happen to have on hand first, and if it works, well, I stick with it.
 
The stone is 2 days old. I will need to pick up a dmt stone to flatten.

The steel will only produce a very fine burr when the stone is dry. Otherwise I will sharpen then alternate when I think it is time to sharpen the back since no burr forms. Im not saying its the steels fault, but its not out of the question. Other steels (154cm and tool steel) will get a burr when I sharpen with the stone. Technique could be the problem just as likely because it is a very low angle I'm sharpening on a soft steel. It cuts and is sharp but I found it odd that the specific steel never formed a burr when sharpening with a wet waterstone.

Is it entirely possible for the edge to be so thin that a burr wont form?The steel too soft to form a burr? The angle of the chisel edge is roughly 10 degrees. I
resharpened it now and it is plenty sharp to carve wood and slice leather. Something is telling me it can get a bit sharper.
 
If the stone is of the softer variety and generates a lot of loose grit, that could prevent/inhibit burr formation. Oftentimes there is a small one there anyway, but the frosted appearance created by mild lapping action makes it a bit more difficult to spot.

On a hard clean stone, having some water on the surface shouldn't effect burr formation much if at all.
 
Your probably using to much pressure. Lighten up and try again.
 
Just out of curiosity how fast are you working?

I meet and see lots of new sharpeners who hump away at a stone like a jack rabbit in the middle of mating season. Meanwhile all this speed only breeds inconsistency (for new sharpeners). My advice is to slow down, mark your edge and use light pressure. If the 1k is your only stone its probably not that great of a starting point if your tools have never been touched up someone who knows what they are doing. You may even need that Diamond plate just to remove all the convexity and rounding from the tool.

Your not getting a burr from either not reaching the edge or spending too much time there. Hard to say without pictures.
 
I remember my first time I tried a water stone. I dulled the crap out of my knife and couldn't figure out why.


Inconsistent angle and/or pressure. I kept holding the knife at different angles each pass and didn't notice it.


You'll learn in time I really bet that's the issue. Most people like to blame the steel or the stone when in reality it's them.

You don't need a super flat stone for a knife. It's not a straight razor, just a knife.

Keep practicing and you'll get it.
 
I will slow down when I sharpen, that could be part of the problem.

The chisel is plenty sharp. It can push cut paper and whittle wood well, just never had a burr form. I guess if it works I will keep doing it. The edge has a very minimal amount of steel behind it. closer to retractable knife thickness.

I will be getting a white number 2 japanese steel knife in the mail I can practice on.

Question. Do you tell if you are sharpening correctly by the specific sound of the stone while sharpening? I hold the bevel at the angle that completely lays flat (moderate pressure) with no space between the stone and knife and listen to a specific sharpening noise to know I'm staying consistent. I sharpen one side, flip and sharpen, then finally alternate sides with progressively softer strokes.

Is that a decent method?
 
Here's what I would recommend for you.

I wouldn't worry about which kind of knife steel it is. That's besides the point for now. Steel is steel. Stones abrade steel.

I would use a black sharpie and mark the bevel. The whole length of the blade.

When you put the knife on the stone lay put it edge down at 90 degrees like you are trying to cut right through the stone, then drop your angle half of that to 45 degrees and then half of that to around 22.5 degrees.

I would start at the heel of the knife and work my way to the tip. With smooth passes, if the blade has a curve to it which I am assuming it does you're going to have to lift your right hand up, while keeping a consistent angle. This will ensure you are sharpening all the way up the tip of the blade. When you see the sharpie being wiped off in a single pass, you know that's your angle.

I wouldn't use a ton of pressure just moderate.

Great end technique, do laps on one side of the knife then flip and do the other. Then alternate, while going lighter and lighter.

Refresh the bevel marker often so until you know you're keeping a consistent stroke. It is a great method.

Your knife will make a sound and eventually you will hear when your angle is off. Really depends on which type of stone for which type of sound is heard, coarse stones will sound scratchy and loud while fine will be less loud and a smooth draw sound.

You've got the idea the trick is figuring out how many strokes to use.

You want space between the knife and stone. Start with a basic 22.5 degree angle but honestly it doesn't matter which angle you hold it at it doesn't have to be exactly 22.5 as long as it is consistent every time.
 
I also say technique, are you going too fast? Is your arms consistent?

I ask this because I corrected a coworkers sharpening habit of going too fast or too long.

I never spend more than 2 or 3 minutes on a 1000 grit. Just enough to raise a burr.
 
I will keep sharpening times around 3 minutes going a steady pace. I keep my forearms locked and push with my shoulder/upper body.

I will check out the sharpie trick, I always though it was a good method but I forgot about it.

I believe the reason I am not getting a burr is because the ceramic stone is so abrasive on the carbon steel that it breaks off. Im curious if a softer stone will get a sharper edge on carbon.
 
Softer stones round the edge more at the medium grit and require more edge trailing strokes to get results. It's also not recommended that soft stones be used to sharpen chisels, ever.

If the steel is VERY hard the burr can be small and often break off when the bevel slopes form an apex. This does not happen a lot but it's possible. If the resulting edge is sharp and has no burr then I guess you have no issue?
 
Jason B. said:
Softer stones round the edge more at the medium grit and require more edge trailing strokes to get results. It's also not recommended that soft stones be used to sharpen chisels, ever.

If the steel is VERY hard the burr can be small and often break off when the bevel slopes form an apex. This does not happen a lot but it's possible. If the resulting edge is sharp and has no burr then I guess you have no issue?
Click to expand...


+1 to the last part of your post. Why worry about the burr?

If it's sharp and burr less you're doing fine.
 
Im not sure why I could still get it sharp with no burr forming. The no burr probably has to do with the angle or me not reaching the apex. Im not sure.

I added a 30 degree micro bevel and the blade is just that bit sharper that I felt was missing. There was a burr when I grind it down.

I always heard about micro bevels but now I can tell its easy to grind and I can still have a thin primary edge.
 
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