Technique issue or stone issue?

[xdoomsongx]

Hello, new to the forum. I searched around, and was unable to find any posts relevant to my question, but if there is something feel free to point it out. I have always used typical hardware store stones to sharpen, but recently started getting interested in the Japanese water stones. I like to try stuff before really committing so I picked up some off brand stones from Amazon. One is a Blue Sun 600/2000 and the other is a Blue Sun 3000/6000. I've been pretty impressed with the 600/2000 so far, very capable of providing a working edge, and rather quickly I might add. However, when I move to the higher grit stones, without changing my technique I seem to lose the working edge and end up with just dull.

I'm wondering what I might be doing wrong, and I'm not familiar enough with the material to know what it could be. I'm building the burr on the 600 then the 2000, but can't seem to get a burr going on the 3000. It took me about ten minutes a side to get my old Gerber gator to a good working edge with the lower grit, but then I spent about an hour on the 3000 grit and it just didn't seem to be coming along. I tried sharpie to make sure my angle was good. Not sure what else to try.

Could I be using too much pressure? If not, any other thoughts of what might be going on? Thanks for the time and help! Despite the problem, I'm excited to be trying something new after all this time, and I love how much quicker it went than my old oil stone.

 

[Ourorboros]

Without seeing, this is just speculation:
If the stone is softer, you may be digging the edge in a little. Sometimes you don't feel fault mechanics on a softer stone.

 

[bgentry]

Waterstones are a different animal. I've found that I have to be WAY more careful with waterstones than with harder stones or plates. I think that they don't give you as much tactile sensation as harder stones, so you don't feel your angle variations as much as with others. Thus you can dig the edge into the stone and not feel it like you normally would.

When I go nice and slow I can get some really impressive edges with waterstones. But the moment I start trying to be "efficient" and make things happen a bit faster... boom disaster. I've almost given up on my waterstones because of this. They sit unused. This is my shortcoming; not the stones.

Go slow and I think you'll be rewarded. Also, try doing *only* edge trailing on the high grit stones to finish.

Good luck!

Brian.

 

[xdoomsongx]

I'll try a lighter hand and see what happens .I was hoping to save some time. Might have to just get some dmt stones. Thanks for the input. I'll let you know if I manage better results.

 

[Wowbagger]

I'm wondering what I might be doing wrong,

Trying to hold a piece of steel in your soft hands, with more than likely play in the pivot and flexure in the blade and hold it on the stone at a consistent angle, trying to not vary the angle by more than a small fraction of a degree and follow the belly of the blade at the same time and then repeat the same on the opposite side over and over.
In other words :
skip the fleshy soft clamp (your hands)
avoid the pivot and blade flex by supporting the blade directly on a fixed hard surface.
hold the stone in a rigid mechanism capable of maintaining a consistent relationship between the stone and the edge.

In other words . . . simply use a sharpening jig. After all if you wanted to drill a hole square to a surface you would use a drill press, if you wanted to draw a straight line you would use a ruler.
What's with all the guessing, holding your tongue just right and hoping when it comes to machining a precision angle on each side of a knife edge ?

 

[Gvard]

Waterstones gave me cancer, so I'll never use them again. I've tried a couple and never got the results I got from other stones like SiC, diamonds and ceramics. The main difference is that waterstones often are softer than other stones. You might be digging the edge into the stone without noticing it. Also, for finishing stones, keep the slurry off the stone as it may dull your edge.

 

[HeavyHanded]

From another conversation:

To me, I consider everything on a continuum from stuff like diamond plates or ceramics to leather or linen strop. Between you have vitreous stones, waterstones, lapping films, wet/dry, knife boards (hard strops), and softer strops.

All of these can be described by how immobile is the abrasive, how much give it has in line with the direction of movement and how much give it has away from the direction of force.

These three factors and one other (the amount of abrasive potential per unit - the mineral characteristics of the abrasive particle) account for the mechanics of abrasion and how it effects the steel, mostly in terms of shape/angle of force and burr formation.

Stropping is at one end, ceramics and diamond plates at the other.

Hello, new to the forum. I searched around, and was unable to find any posts relevant to my question, but if there is something feel free to point it out. I have always used typical hardware store stones to sharpen, but recently started getting interested in the Japanese water stones. I like to try stuff before really committing so I picked up some off brand stones from Amazon. One is a Blue Sun 600/2000 and the other is a Blue Sun 3000/6000. I've been pretty impressed with the 600/2000 so far, very capable of providing a working edge, and rather quickly I might add. However, when I move to the higher grit stones, without changing my technique I seem to lose the working edge and end up with just dull.

I'm wondering what I might be doing wrong, and I'm not familiar enough with the material to know what it could be. I'm building the burr on the 600 then the 2000, but can't seem to get a burr going on the 3000. It took me about ten minutes a side to get my old Gerber gator to a good working edge with the lower grit, but then I spent about an hour on the 3000 grit and it just didn't seem to be coming along. I tried sharpie to make sure my angle was good. Not sure what else to try.

Could I be using too much pressure? If not, any other thoughts of what might be going on? Thanks for the time and help! Despite the problem, I'm excited to be trying something new after all this time, and I love how much quicker it went than my old oil stone.

If the stone is soft - prone to forming mud or slurry - it will not easily form a burr at the finer abrasive size. The fact you are having trouble crafting one at 3k is a tip off maybe that this is the case.

With the 3k and 6k, finish with a few trailing passes once you have overground the previous finish, maybe four or five per side alternating or no. As already mentioned keeping the stone rinsed is helpful. Keeping a lot of water on the surface also helps - refresh with a gentle pour as the slurry builds up to keep the water on the surface fairly clear.

My Nortons are the same way - sometimes even the1k will not form a burr on some steels and finishing with a leading pass results in a burr free but not very sharp edge.

 

[xdoomsongx]

Thought I would update, I tried a lighter hand and keeping the stones clear of slurry. I have been able to achieve much better results. Also, I tried a work sharp Ken Onion with the blade grinding attachment recently. Shaving sharp just shy of ten minutes. I'm going to have to order that setup for sure. Thanks for the help!

 

[115Italian]

Try raising a bur at coarser grits and then get rid of it. At 2000 grit I wouldnt try to raise a bur. Just refine the edge at that point with light pressure. You might be over working the edge on the finer stones.

 

[leozinho]

Trying to hold a piece of steel in your soft hands, with more than likely play in the pivot and flexure in the blade and hold it on the stone at a consistent angle, trying to not vary the angle by more than a small fraction of a degree and follow the belly of the blade at the same time and then repeat the same on the opposite side over and over.
In other words :
skip the fleshy soft clamp (your hands)
avoid the pivot and blade flex by supporting the blade directly on a fixed hard surface.
hold the stone in a rigid mechanism capable of maintaining a consistent relationship between the stone and the edge.

In other words . . . simply use a sharpening jig. After all if you wanted to drill a hole square to a surface you would use a drill press, if you wanted to draw a straight line you would use a ruler.
What's with all the guessing, holding your tongue just right and hoping when it comes to machining a precision angle on each side of a knife edge ?

View attachment 877208

I guess it’s a miracle that I - along with hundreds of thousand (millions?) of men through time to include your grandfather - have been able to produce sharp edges freehand.

I’m not saying you are a lesser man because you can’t freehand sharpen. I’m sure there are dozens of others that gave up too.