How high do you go????

[Peter Scoma]

Curious to know what final stone (oil, water or sandpaper) most members finish off their sharpening repertoire with. I, like many others I imagine, am always in pursuit of taking my sharpening to the next level. Right now I finish with an 8k grit waterstone. John reed fox mentions in an old woodwrights segment that he finishes with a 30k grit stone which can be found on the bay of all places for a cool 350$. Just wondering if a 15k or 30k stone is worth it I suppose. I'm already getting nice thin gossamer shavings ending with 8k but as I mentioned, the holy grail of sharpening evades me.

PS

[Allan Froehlich]

Maybe you could try buffing compound on a leather wheel.

[Derek Cohen]

Hi Peter

Do you actually need a sharper edge than you currently get? Or are you just curious?

I probably use my leather strop (with .5 micron/=30000 grit green rouge) more often than I use my Shaptons.

With a microbevel created on a hollow grind, I use the 1000 to straighten the bevel edge and then the 12000 to polish it. Honing a newly ground edge takes in the region of 2 minutes max.

Regards from Perth

Derek

[George Beck]

Peter

I too am always chasing the perfect edge. I progress from 8,000 to 15,000 to 30,000 on plane irons. Alex Gilmore on his interesting web site http://thejapanblade.com/ has natural water stones that can reach 48,000, although I cannot imagine using a $2,000 stone. My findings have been that I cannot achieve a sharper edge with the 15,000 or 30,000 grit stones but the edge does stay sharp longer and requires less honing to bring it back. I will attempt to explain. I performed a completely unscientific experiment. I sharpened one plane to 8,000 and could take very fine shavings. I then took another plane with the same blade (Hock high carbon rc65) and sharpened it though 15,000 and finished on 30,000. I planed some cherry posts scrap from 1 in thick to about 1/2 in thick (a lot of shavings, I was ankle deep in fine shavings!). The first blade was loosing its edge about half way through whereas the second held its edge much longer. I also find that the finer stones make more of a difference on high end Japanese blades. On my Lie Nielsen chisels (A2 steel)) I do not see any measurable difference. I lack the expertise to know why this is so but my theory is that the finer the scratches the stronger the edge which makes sense. The perfect unattainable goal I would suppose would be to achieve No Scratches or perfectly smooth. I have found the decision in sharpening is whether to sharpen as fine as possible or hone more often. Some wood carvers never sharpen beyond 5,000 or 6,000, however they hone and strop continuously.
My sharpening skills are evolving and changing. I used to worry about the entire back and edge being "shinny" whereas now I worry mostly about the formation of the "burr" at each grit level. I also sharpen tools differently depending on what I am doing. For instance; I do not have the luxury of owning a lot of chisels in the same size, so I was using a wide chisel to chop out the waste in a plane dai and latter needed to use the same chisel to pare tiny amounts away for final fitting. This required two different edge requirements. Anyway, these are some of my sharpening experiences. A journey I doubt will ever end.

George

[Julian Nicks]

I don't fuss with anything expensive. I just cut a 6" wheel out of 3/4 particle board, and mount it in my slow speed grinder, and put jewelers rouge on the side. It only takes a few seconds on each side of the chisel/plane on the wheel to touch up a dull or freshly ground edge and I'm back to work( the most imortant part). No fancy stones, or systems needed.

[Mike Henderson]

First, I'm not convinced that honing to that level makes much difference.

But if you want to do that, rouge or the green honing compound is a lot less expensive than a really high number stone (such as a 15K). If you're concerned about rounding the edge, put the honing compound on something like MDF and hone on there. And as Derek pointed out, you only have to hone the edge, not the whole bevel.

Mike

[David Keller NC]

"I also find that the finer stones make more of a difference on high end Japanese blades. On my Lie Nielsen chisels (A2 steel)) I do not see any measurable difference."

There is a discussion of why this is so in Toshio Odate's "Japanese Woodworking Tools: Their Tradition, Spirit and Use", complete with photomicrographs to prove the point. Well worth owning this book, and it's been reprinted and is very inexpensive, especially used, on Amazon.

[Matthew Dworman]

I've played with 15/16K stones, but I think after 8K you reach the point of diminishing returns. i.e. perhaps the edge you get with a 15k stone will last 5 or 10 strokes before it is reduced to the edge you get after 8k - this will last for 40 or 50 strokes before it is reduced to the edge received from a 4k stone etc...
I think the extra time put into anything past 8k is not worth it. Instead, use that time to re-hone a blade that needs a touch up.
my $0.02

[Jeff Dege]

I'm an absolute novice at woodworking, but I do know knife sharpening. Going to a finer grit than you need isn't just a waste of time, it can make for a less effective tool. For every task there is an appropriate level of roughness. For some tasks, you want razor smooth. For others, the small-scale roughness left by a medium grit stone makes for an easier cut.

You shouldn't be asking how fine an edge you should be trying to get, you should be asking what is the appropriate edge for the task at hand. Planing end grain with a block plane, leveling a benchtop with a smoothing plane, cutting a mortise with a chisel - these have very different cutting actions, so I would expect that they would work best with different edges.

[John Schreiber]

With plane blades, I haven't found any advantage to going beyond 2000 grit sand paper. I can strop to a finer edge and it cuts the hair off my arm better, but I don't find that it cuts wood better.

I haven't tested with carving knives or chisels, but I'm beginning to suspect that a tiny bit of tooth on knives can be a good thing, especially on softer woods.

[David DeCristoforo]

This is in the same category as the discussions about how accurate you need to be. If you can shave hair with the blade, it's plenty "sharp enough" for woodworking. Beyond that you are satisfying something other than "need".

[Jeff Dege]

With plane blades, I haven't found any advantage to going beyond 2000 grit sand paper. I can strop to a finer edge and it cuts the hair off my arm better, but I don't find that it cuts wood better.

I'd expect that it'd dull faster.

[David Keller NC]

You shouldn't be asking how fine an edge you should be trying to get, you should be asking what is the appropriate edge for the task at hand. Planing end grain with a block plane, leveling a benchtop with a smoothing plane, cutting a mortise with a chisel - these have very different cutting actions, so I would expect that they would work best with different edges.

Jeff - Don't doubt you on the knife sharpening - anyone that's ever tried to cut bread with an smooth, highly polished blade figures out quickly that a rougher (and better yet, serrated) knife cuts considerably more effectively.

That said, there is not, to my knowledge any WW handtool that doesn't cut more effectively and with less effort if it is sharper.

However, that's a different question to the need for sharpness and the effort required to get it to that point. A smoothing plane's blade needs to be way beyond razor sharp for the best surface left behind (in my book, "way beyond razor sharp" is correct honing on an 8000 grit waterstone or equivalent). But I find very little to no benefit by spending a lot of time on a fore plane blade beyond getting it to "feel sharp" - I don't sweat little nicks in the blade, and will use it without honing far past where I'd touch up a smoothing plane blade.

It's a good point - thanks for adding it to the discussion

[Jim Koepke]

Interesting subject that we will likely be debating beyond our days and into eternity.

My last visit to Hida Tools in Berkeley, CA was interesting. There was a collection of natural stones of different sizes that left me stunned at the prices. Someone must think they are worth it.

My finest stone is an 8000 water stone. Surely there is an advantage to having a finer stone. There is also an advantage to not angering SWMBO by trying to convince her another stone is needed.

Ron Hock said at a trade show, people are not buying his blades, they are buying the surface they make.

Fresh off the 8000 stone, even my #8 can take full width gossamer shavings leaving a glassy surface on a piece of pine. Never thought of a #8 being like a smoother. This can sometimes be done with finishing on a 4000 stone.

So why bother? finishing the blade at 8000 gives an advantage if there is a shift in the grain. This is a common occurrence with the less costly pine used in a lot of my projects. Finishing with a 4000 stone will often leave a little tear out.

IMO, the sharpening is not for the blade, it is for the surface the blade leaves behind.

jim

[Jim Koepke]

This is in the same category as the discussions about how accurate you need to be. If you can shave hair with the blade, it's plenty "sharp enough" for woodworking. Beyond that you are satisfying something other than "need".

This has me thinking. Because of the cold weather last winter, and my being from California now living in Washington, I grew a beard. Now it is getting time to cut it off. In the past I used a straight razor, for long hair, they tend to work best for me. Not sure where it was put for the move or even if it made the trip. Was thinking of using one of my plane blades.

As long as the edge is not rounded, I can cut hair with a blade off of a 1000 stone. It is not comfortable. The finer the stone, the less the hairs get snagged in the little crevices in the blade. For shaving hair, one does not want any roughness to the blade.

jim