I hate to start another sharpening thread...but

[JohnMorgan of Lititz]

Here goes...

I used to use the sandpaper on granite block method of sharpening. I would usually start around a 320grit or 600/800 grit all depending on what i was doing. I would finish up through 800, 1500, and then 2000 to polish it all off. I realize i can buy the super micro grits - we won't go there on the discussion...I stop at 2000.

I then decided after much review of things and sitting through a David charlesworth class that day-to-day sharpening works really well on 800, 1200 and 8000grit water stones. So I purchased the 3 stones - rather inexpensive. I also decided to switch over because i was tired of occasionally tearing sandpaper.

The real question of this thread:

I purchased 3 LN chisels a few months back and never got around to putting a mirror polish on the back side. So I though I would take the time to work on this. I noticed that 2000 grit sandpaper puts a much cleaner polish on the backs much much quicker than my 8000 grit waterstone.

Am I doing something wrong? I surely thought my 8k waterstone would polish quicker and produce a better result. The 8k doesn't even really polish to a mirror - its a very hazy mirror. While the 2k paper literally puts a mirror shine on blade.

I am a strong advocate of flattening my waterstones while i sharpen, but just to be sure, I double check them for flat with a staright edge - corner to corner and front to back it all checks out.

Any thoughts or is this just the difference between the two cutting surfaces?

[Robert Rozaieski]

Grit sizes are rather subjective. Actual micron particle size is a better measure. I believe an 8000 grit waterstone is actually not as fine as 2000 grit paper when you look at particle size in microns.I may be mistaken as I have not seen the numbers in awhile but I do know that waterstone grit sizes and sandpaper grit sizes do not mean the same thing, i.e. 1000 grit sandpaper is not the same as a 1000 grit waterstone (the 1000 grit sandpaper is much finer than the 1000 grit stone).

[Joe Feistritzer]

John, great question. I'm still pretty new to sharpening. I have Norton water stones and decided to try the scary sharp method with sand paper and a granite backer. I get the same results on the mirror finish. The sand paper gives a much shinier mirror than my higher grit (?) water stone. How is that? Thanks to whoever has the answer...

[Jim Koepke]

This is similar to my experience. Sandpaper with about a 9 µ size would polish to a mirror when my stone with about a 1 µ size would be hazy. It shaved smoother than a razor, so it didn't bother me much. Now that my stone has been used a bit, it does not seem to cloud the surface being sharpened.

My stones are from a variety of makers. As they get replaced, my preference may be to stick with one brand. May even try switching to the Spiderco sharpening system.

Currently, water stones seem to work best for me. Others do not like the mess and hassle.

jim

[Joe Feistritzer]

Jim, Thanks. My stones are still very new. I didn't think that there may be a breaking in period. If teh haze is only cosmetic, then I care a lot less than I did. It seemed that maybe I just wasn't getting the result I wanted...a flat back and a sharp chisel and/or iron. Cosmetics I can live with as the wife never ventures into the shop.:rolleyes:

[Jim Koepke]

Here is a link to a thread with a .pdf of a grit size comparison chart.

http://www.sawmillcreek.org/showthread.php?p=1062936&page=2

My thoughts is there may be a coating on the stones to protect them during shipping and handling. After a little use this likely wears away.

just my 2¢,

jim

[David Keller NC]

"Am I doing something wrong? I surely thought my 8k waterstone would polish quicker and produce a better result. The 8k doesn't even really polish to a mirror - its a very hazy mirror. While the 2k paper literally puts a mirror shine on blade."

There's two potential questions here. From the standpoint of flattening the back and removing factory grinding marks, the 8000 grit stone is going to be exceedingly slow at doing this if that's the grit you're starting with (not sure if that's the case, but thought I'd mention it). How much metal is removed is not only a function of the grit size but also properties of the binder and the friability of the grit itself. An 8000 grit stone is specifically manufactured to "glaze" - the released grit particles break down and combine with the binder and steel particles to make a slurry that's much finer than the grit on the freshly-surfaced stone. This is what you want for polishing, which is what these stones are for.

What you might be seeing as to the "mirror" effect isn't really a case of the sizes of the scratches on the surface. I can get a very bright, shiny look to the back of my chisels on the coarse diamond plate that I start the flattening process with, though there are lots of unacceptably big scratches after using this stone, to be polished away by the subsequent 1000, 4000 and 8000 grit stones.

My guess is that the "gray" look to some steels when polished on waterstones has something to do with a chemical reaction of the binder and the very surface of the steel. I notice this especially with A2 steels, but it doesn't affect sharpness or flatness, so I don't worry about it.

If it bothers you, you can make the steel "silvery bright" by lightly stropping the back on a strop mounted on a flat surface.

[Jim Koepke]

Another thing to consider is sandpaper has a limited supply of grit compared to a stone. As sandpaper is used the sharp edges on the grit get rounded over and may be more likely to polish than abrade.

Have done more thinking about abrasives before breakfast than most people do all day.

jim

[David Romano]

This all sounds abit suspicious to me. In looking at various charts of grit vs "mesh" vs micron size, there is definitely some uncertainty as to what micron an 8000 grit stone is, but not enough to confuse 2000 grit anything with 1 micron. I have the Norton waterstones and find that I get a beautiful mirror polish with the 8000 grit. In my experience, and as per Norton, it is is important not to contaminate the higher grit stones with the lower grit slurry. For this reason, the idea of a "stone pond" with more than 1 stone in it makes no sense to me. I find that I don't get a nice mirror polish if I have alot of cross contamination.

[Mark Roderick]

I do get a mirror finish from my Norton 8,000 grit stone. I don't know why.

I also don't know whether a mirror finish "proves" the metal has been abraded with a fine abrasive, or that shinier necessarily equates with finer. It sort of makes sense intuitively, but we might need a PhD in materials engineering to answer the question.

[JohnMorgan of Lititz]

This all sounds abit suspicious to me. In looking at various charts of grit vs "mesh" vs micron size, there is definitely some uncertainty as to what micron an 8000 grit stone is, but not enough to confuse 2000 grit anything with 1 micron. I have the Norton waterstones and find that I get a beautiful mirror polish with the 8000 grit. In my experience, and as per Norton, it is is important not to contaminate the higher grit stones with the lower grit slurry. For this reason, the idea of a "stone pond" with more than 1 stone in it makes no sense to me. I find that I don't get a nice mirror polish if I have alot of cross contamination.

You've touched on what I was wondering may be the issue. I may have flattened the 8k stone with a 320g paper that had 1200grit stone slurry on it.

I probably should go back through and clean everything and try again. What a mess though - and a pain in the ...

[Jim Koepke]

I do get a mirror finish from my Norton 8,000 grit stone. I don't know why.

I also don't know whether a mirror finish "proves" the metal has been abraded with a fine abrasive, or that shinier necessarily equates with finer. It sort of makes sense intuitively, but we might need a PhD in materials engineering to answer the question.

Not sure about the engineering degree. Many of the engineers in my experience could not reliably distinguish between a hole in the ground and another well known hole.

A mirror finish is not the point of sharpening. It may be a collateral effect. The focus of sharpening is the arris. The edge formed by the meeting of two surfaces. Many people do not like the "shave the arm hair" test. I will agree that it is not the end all be all test for honing a blade. It will give valid indications of the condition of a blades edge.

1) If the blade just rolls over the hair, it is not sharp.
2) If the blade removes a few hairs, but snags, then there are likely small little nicks at the edge or some other imperfection catching the hair. Check for a burr (wire edge) and remove if one is found.
3) If the blade removes a few hairs without snagging, then the edge is likely free of nicks and could be put to use. It is also possible to get it a little sharper.
4) The blade removes every hair in its path and it feels like nothing is happening. You may in fact think there is nothing happening and are surprised when you lift the blade to find a bunch of hair resting on the blade. This is the time to stop trying to get the blade sharper. Unless you are real good at sharpening, it is just as likely that you will either just remove more metal or damage the fine work you have already done.

These are the main things, in my experience, to look for. Depending on one's skin condition, duller blades may also pick up a few flecks of skin. A sharp blade with a back bevel may leave stubble.

This test is not for everyone. Use extreme caution when doing this test. Lack of attention could result in a trip to the local emergency room. It requires a delicate touch and knowing how to use the blade. Many years ago, I used to shave with a straight razor. This experience in blade to face interface has likely helped in my chisel to arm hair testing.

jim

[Rob Luter]

Not sure about the engineering degree. Many of the engineers in my experience could not reliably distinguish between a hole in the ground and another well known hole.

This Engineer can tell the difference. I had a special class in college. :D

[David Romano]

You've touched on what I was wondering may be the issue. I may have flattened the 8k stone with a 320g paper that had 1200grit stone slurry on it.

I probably should go back through and clean everything and try again. What a mess though - and a pain in the ...

I agree, what a mess. Besides the Norton flattening stone not being flat, and being very difficult to make flat, the contamination issue is the reason why I bought a DMT Diasharp. It's easy to clean, pretty flat (not quite like a granite surface plate) and durable. Plus, I can use it for my jointer blades as well!

Dave

[David Keller NC]

"You've touched on what I was wondering may be the issue. I may have flattened the 8k stone with a 320g paper that had 1200grit stone slurry on it.

I probably should go back through and clean everything and try again. What a mess though - and a pain in the ... "

While it's possible you've embedded bigger grit in the 8000grit stone, it's doubtful. There is no need to flatten the finer stones on really fine sandpaper. Not only would that take forever, but the stone binder will prevent grit embedding in the surface unless you press really hard as you're flattening. That's a bad idea anyway, as it will likely lead to a dished or bowed surface on the stone.

What is critical is to remove all of the slurry off of the surface - under running water. If you don't have this facility in the shop, you can rinse them off with the hose or in the upstairs sink. After this, it's not necessary to get the surface really clean so long as you're careful not to cross-contaminate the stone with bigger grits on the back of a chisel or plane blade.

[JohnMorgan of Lititz]

What is critical is to remove all of the slurry off of the surface - under running water. If you don't have this facility in the shop, you can rinse them off with the hose or in the upstairs sink. After this, it's not necessary to get the surface really clean so long as you're careful not to cross-contaminate the stone with bigger grits on the back of a chisel or plane blade.

I usually end up dunking in a bucket of water at the workbench and "scrub" the stone clean with my fingers.

So flattening the 8k stone on 320grit sandpaper on my granite block should work just fine you think?

[Jim Koepke]

This Engineer can tell the difference. I had a special class in college. :D

I wish more engineers had taken that class. It should be a requirement.

One engineer told me I could not possibly know about the passivation of aluminum since I was not an engineer. He had not heard of it, so therefore it was not possible.

Another engineer looked at me like I was out of my mind when I was trying to explain the growth of dendrite on circuit boards. Had to bring in a paper from HP Labs before they would consider this was the problem we were having.

An engineer where I worked refused to believe that there is such a thing as harmonic resonance. There was one piece of equipment that kept flying apart. I did some calculations and found a lot of the parts were the same nodal length as the frequency at which it ran. Of course, my not being an engineer meant I could not possibly know about things an engineer did not know about.

Another was always wasting my time by having me going to his area to trouble shoot equipment when most often it was because he forgot to plug something in.

On one job an engineer refused to listen to suggestions from people who built and worked on the equipment because we could not possibly know what the engineers who designed the equipment knew.

When I was a field service tech, a roller had to be replaced in a machine because an engineer used a knife to remove a piece of paper that had wrapped around it. The machine had a bright yellow warning sticker next to the roll explaining not to do this. When asked if he read the sticker, he said yes and that he did not see any electrical wires and thought it would be OK. I asked him to read the sticker again. He acted like he was reading and then stated again about there not being any wires. His refusal to read the sticker, that said nothing about electrical hazards, cost his company about $400, this was almost 20 years ago when $400 could buy more. That job put me in the company of more engineers than any other job. It made me wonder why a lot of things don't just fall apart all the time. Fortunately, many of the people in the trenches know what is going to work and what is not.

On the other hand, I did meet a lot of engineers that made me feel like buying stock in their companies would be a good idea.

Then again, don't get me started on architects. My father owned a furniture and appliance store. Delivering these items to many homes convinced my brothers and I that architects should be required to spend a few years moving furniture before they are allowed to put pencil to paper on any project.

jim

[Tri Hoang]

I found that a mirror/shiny surface is easier to get on a 4000 waterstone and a straight honing motion. As the stone get drier and more steel particle clog there, the back get shinier. It's possible to do it on the 8000 but as soon as it get a little dry there, the blade tends to get sticky and harder to move.

I have occasional problem with grit contamination just by moving from one stone to the next or by the wire edge floats off and stays on the 8000. A few strokes and the previously shiny/mirror polish back would show multiple scratches. So I'd carefully wipe off everything before moving on to the next grit. In addition, if you hone free hand, you could feel when there's a little contamination.

[Joe Close]

...architects should be required to spend a few years moving furniture before they are allowed to put pencil to paper on any project.
jim

LOL... I thought I was the only one who thought that way!!!! That would make a good signature line quote.... :D

[Ray Sheley]

"Not sure about the engineering degree. Many of the engineers in my experience could not reliably distinguish between a hole in the ground and another well known hole."

Well actually I can relate. At one point in my career I was an Automation Engineer, we designed, worked with our shop hands to build, then troubleshot and made the automation assembly loops ready for production. We were part of the Tool Engineering department, and the Research and Design boys would refer to us as the Blue-Collar Engineers, because they considered us to be of a lower standing than they. Our personalities and behaviors were a "bit " less refined than theirs, and we actually got our hands dirty when doing machine adjustments and experiments. What's worse, a surprising number of us in this group actually came from a Blue-Collar background as compared to the suburb/elite class that many of "the other" engineers grew up in.
The reverse side of the coin was that we of course assumed that many of them spent a fair amount of their high school years stuffed headfirst in a trash can, gently placed there by us coarse blue collar types. And probably patronized them just as much, because of our perception that they could not do much in the way of hand labor that was meaningful. However with specilized equipment such as this you spend a lot of hours working with all the different types from shop rats to Research types and in the end you find that most are pretty good folk once you relax and get to know each other. I've got a lot of good memories across the labor lines during my career. It's too bad that we have driven manufacturing off shore, these next generations will miss out on that experience.

[Jim Koepke]

...architects should be required to spend a few years moving furniture before they are allowed to put pencil to paper on any project.

jim



LOL... I thought I was the only one who thought that way!!!! That would make a good signature line quote.... :D

I am sure anyone who has wrestled with furniture or appliances trying to get it into homes, condos or apartments has had this thought.

If it is original to me, I could start a movement. The easy furniture movement...

jim

[Jim Koepke]

However with specilized equipment such as this you spend a lot of hours working with all the different types from shop rats to Research types and in the end you find that most are pretty good folk once you relax and get to know each other. I've got a lot of good memories across the labor lines during my career. It's too bad that we have driven manufacturing off shore, these next generations will miss out on that experience.

Hopefully I did not unload too heavily. I have also worked with great engineers and other people across the lines.
In my own life experience, there were not too many jobs from which I would shy away. Sometimes when asked where I have worked, I would kid people by telling them it might take less time to tell them where I haven't worked.

jim

[Ray Sheley]

Hopefully I did not unload too heavily.

jim

Jim,
I'm not in the least offended, but can completely relate. Over the years I feel that I've had a great relationship with all the layers of folks that are in manufacturing, and I have a great respect for the knowledge and experience for each position.

It's a foolish Engineer who won't listen and learn. Your co-workers are your best allies if you let them help, generally speaking you all want the same result. Trying to do it without knowing all the facts is a pretty futile effort.

And true confession time " I too have had moments of great stupidity where I just didn't undertsand the problem and had to be brought up short by those that knew." You try to be humble and respectful, but sometimes you just have those "DUH!" moments.

[David Keller NC]

"So flattening the 8k stone on 320grit sandpaper on my granite block should work just fine you think?"

John - Absolutely. I do my own flattening on a granite plate with 220 grit wet-dry sandpaper. I'll note that it's probably not 220g any longer - I use the same piece over and over, because I found there was a "break in" period where one was wearing away the grit more in the center than the edges. If you're not careful to get the stone about halfway past the edge of the sandpaper on each stroke, this differential wearing of the paper can produce a stone with a convex surface. Not really convex, but enough to where it becomes bothersome when flattening the back of a wide plane iron.

[JohnMorgan of Lititz]

John - Absolutely. I do my own flattening on a granite plate with 220 grit wet-dry sandpaper. I'll note that it's probably not 220g any longer - I use the same piece over and over, because I found there was a "break in" period where one was wearing away the grit more in the center than the edges. If you're not careful to get the stone about halfway past the edge of the sandpaper on each stroke, this differential wearing of the paper can produce a stone with a convex surface. Not really convex, but enough to where it becomes bothersome when flattening the back of a wide plane iron.


Thanks, David. I worked on the sharpening some more this weekend and still for some reason seem to get a better polish off the 2k paper. Again, maybe the high polish mirror shine is not a true indicator. Either way, the lastest issue of FWW defines sharp very well I think: Ability to pare end grain of pine.

After spending some time on the chisels and the block plane, I was able to get some decent shaves of end-grain pine. Sharp enough for me! I finally got a decent camber on my LN 4.5 HAF iron and am taking some nice shaves leaving a very good surface. I need to work on the LN 5.5 and LN 7 yet. Then the shoulder plane.

I always sharpen while using the tools, but when you're between projects - as I am now - its nice to go through the tools and clean them up, tune all the blades, etc.

It will be a while until another woodworking project. Right now I'm expanding our bathroom closet into a "Laundry room". The new kitchen cabinets are coming mid July and I need to get the washer/dryer out of the kitchen space. Yes, we live in a small rancher w/ the laundry in the kitchen - and it sucks! :)

[geoff brandenburg]

You've touched on what I was wondering may be the issue. I may have flattened the 8k stone with a 320g paper that had 1200grit stone slurry on it.

I probably should go back through and clean everything and try again. What a mess though - and a pain in the ...

I have four waterstones, four separate pieces of 100 and 220 grit wet/dry sandpaper to flatten each stone on a granite surface plate after I use it — I rinse the waterstones off after flattening and there is no cross contamination on the sandpaper or in the waterstone 'pond'.

Very simple and easy, to me.

[Danny Burns]

"Sharp vs. Shiny & Other Deep Nonsense"

http://www.thejapanblade.com/sharpvsshiny.htm

[Danny Burns]

Thread on Sharp vs. Shiny

http://www.japanesetools.com/phpBB3/viewtopic.php?f=2&t=1937&hilit=dull+shiny

Verhoeven Article.

http://www.scribd.com/doc/10044505/Experiments-on-Knife-Sharpening-John-Verhoeven

[John Keeton]

Either way, the lastest issue of FWW defines sharp very well I think: Ability to pare end grain of pine. :)I find all of this interesting, particularly in light of my newness to actually using sharp tools! However, I also liken much of this to the lengthy, and sometimes contentious, threads on the fine tuning of the top of a tablesaw. Sometimes, it is the process that becomes the final objective. In other words, the goal becomes the ultimate edge rather than completion of the joint or project.

While I admit that I know little of this stuff, I run my tools through my scary sharp board, and immediately run them across the endgrain of a piece of soft wood - usually poplar because I don't normally have pine laying around. If my blade has a shiny surface, easily shaves hair, and it melts through the endgrain - I am done. Honestly, I couldn't care less what a microscopic photo of the edge would look like. I am of the opinion, that after several cuts, my edge will look much like any other edge that started out sharper than mine.

However, if getting the ultimate edge is your thing, then I applaud your efforts. I realize fully, that my position is an acceptance of a certain level of mediocrity - and I am comfortable with that:D

[JohnMorgan of Lititz]

I find all of this interesting, particularly in light of my newness to actually using sharp tools! However, I also liken much of this to the lengthy, and sometimes contentious, threads on the fine tuning of the top of a tablesaw. Sometimes, it is the process that becomes the final objective. In other words, the goal becomes the ultimate edge rather than completion of the joint or project.

While I admit that I know little of this stuff, I run my tools through my scary sharp board, and immediately run them across the endgrain of a piece of soft wood - usually poplar because I don't normally have pine laying around. If my blade has a shiny surface, easily shaves hair, and it melts through the endgrain - I am done. Honestly, I couldn't care less what a microscopic photo of the edge would look like. I am of the opinion, that after several cuts, my edge will look much like any other edge that started out sharper than mine.

However, if getting the ultimate edge is your thing, then I applaud your efforts. I realize fully, that my position is an acceptance of a certain level of mediocrity - and I am comfortable with that:D

Couldn't have said it better myself.

I've found that its always good to research something simply to make sure I'm not wasting effort...and sharpening is one of those subjects. After much reading on this forum and several dvd's of "the big names", I've come to the same conclusion as you. At the end of the day, I want to pare some soft end grain and spend as little time getting to that result.

Cheers.

[jamie shard]

I thought this was the best explaination in all of the links above, from the Thread on Sharp vs. Shiny.

"The consideration of shininess in relation sharpness is about the light refraction of scratches in steel surfaces and its relationship to edge consistency/retention. Generally, deeper scratches suck in more light and look duller while shallower scratches refract light better and look shinier. The geometry of the scratch walls is where things get interesting. More facets in the abrasive create brighter refraction. A smoother particle with fewer facets produces a rounded scratch wall geometry that refracts less light and looks duller.

"This is what's going on with Japanese natural sharpening stones. The particles in these stones have been rounded by nature so they produce a scratch that refracts less light. Some natural stones can produce an edge that is sharp but not really shinny. Under powerful magnification the surfaces left by these natural abrasives look beaten more than scratched."

Seems to make sense. It also explains why 1000 grit waterstones can leave a very shiny surface, because it is obviously not mirror smooth at that point. A 1000 grit produces lots of facets.