Sharpening - Are all the stones really required?

[Sean Kinn]

Newbie here, with an honest chisel sharpening question. I've read all sorts of articles here, and on other sites that have you using 4-6 different stones to sharpen up a set of chisels. I was convinced that I'd be spending at least $100 on a set of the "mandatory stones."

However, while visiting with my father in law this last weekend he showed me his technique. I will preface this by saying he has been a mechanical engineer for 25+ years and is known as one of the best in the US in his field....he knows metals, and his stuff. He's also been working with wood for at least 15 years.

He only used a grinder with a coarse grey wheel, and a small $7 Buck Knives Arkansas stone, and put an edge on the chisel that was able to shave hairs off of my finger. He did point out that the use of the grinder could very quickly destroy a chisel (heat), and that he was only able to do it this way after years of practice. He would only let the chisel touch the grinding wheel for a second at most, and was dipping it in water after each pass. The honing (and back flattening) was then done on the small Buck stone with standard Buck honing oil.

I guess I'm having a hard time seeing the need for all of the fancy stones after seeing the edge he was able to produce. My question is: what real advantage do you get from going to the very fine 6000x and 8000x stones? My chisel is now super sharp, and I don't see how any further sharpening would be beneficial for a chisel. Was this just do to his many years of experience? Are the super fine grits only really beneficial for plane irons? Thanks.

[Greg Crawford]

Sean,

You could always experiment with the scary sharp method

http://www.shavings.net/SCARY.HTM.

Uses sandpaper and a flat surface. You can go as fine as you want without too much expense and make your own decision.

[Sean Kinn]

Thanks for the detailed link Greg, I hadn't seen that particular one before. I'd seen a few other posts about the sandpaper approach while researching sharpening, and to a degree that method was another thing that had prompted my question.

[George Sanders]

I use the scary sharp method. I have taken the temper out of more than one tool on a grinding wheel. I have a good collection of stones purchased at auctions and rummage sales but I find sharpening chisels much quicker with sandpaper on an 18" square of marble that I got for $3.00 at an auction. I use a honing guide to keep the angle the same; although there are some people who can sharpen without one. Sandpaper is a lot cheaper than stones.

[Mike Cutler]

Sean

It all depends on what you are starting with ( material, condition of edge), and what you want to do with it.
Putting a sharp edge on a chisel, plane blade, etc is very easy. Putting a sharp edge on these blades and having them stay sharp during use is a different matter.
Shaving hair is a nice display of "sharp", but if the edge rolls the first time it's used, it's of little use.
There are many ways to sharpen a tool. I use a combination of them.
For tools that are already sharp, I just keep them that way with oilstones, or waterstones. For Flea Market specials, I use the grinder, 220 grit paper, and then stones. I don't think there's just "one way".

Taunton Press has a nice book on sharpening by Thomas Lie-Nielsen. He uses all the different techniques and there are a lot of pictures.
I learned to sharpen knives by being bored stiff on a submarine for 4+ years. ;)

[Greg Crawford]

Sean,

I forgot to mention that since I'm still fairly new to "real" sharpening, I got the Veritas Mk. II honing guide. I've found it useful on stones as well as flat plates with sandpaper. Different blades need different angles, and this accomodates many different angles. Of course, the best and fastest is to just sharpen by feel without a guide, but I'm not there yet.

I also just used an old piece of hard leather for a strop, with the Grizzly .5 micron rouge. It was a cheap way to get that part going. Bags of leather scraps can be found at craft stores like Hobby Lobby for just a few bucks. Glad I did, too, as I've taken a few gouges out of the leather as I've been working on my technique.

Greg

[Derek Cohen]

Hi Sean

I do not have any problem with the method demonstrated to you by your FIL. I essentially do the same - for chisels. However I would not recommend this for plane blades.

Many of my chisels are hollow ground on a dry high speed grinder. I may then use a 1200 diamond stone to hone the microbevel, and then strop it on green rouge on leather. This will pop hairs off your arm.

... but this edge may be too serrated for a smoother. Moving through the grits .. Shapton 1000/5000/8000 helps create a SMOOTH final bevel.

One last point regarding jumping grits - it is OK to do so if you are honing a microbevel. More than this increases the area to be honed, and too much area will create more effort (and stone wear) than desirable.

Regards from Perth

Derek

[Randal Stevenson]

He only used a grinder with a coarse grey wheel, and a small $7 Buck Knives Arkansas stone, and put an edge on the chisel that was able to shave hairs off of my finger. He did point out that the use of the grinder could very quickly destroy a chisel (heat), and that he was only able to do it this way after years of practice. He would only let the chisel touch the grinding wheel for a second at most, and was dipping it in water after each pass. The honing (and back flattening) was then done on the small Buck stone with standard Buck honing oil.

I guess I'm having a hard time seeing the need for all of the fancy stones after seeing the edge he was able to produce. My question is: what real advantage do you get from going to the very fine 6000x and 8000x stones? My chisel is now super sharp, and I don't see how any further sharpening would be beneficial for a chisel. Was this just do to his many years of experience? Are the super fine grits only really beneficial for plane irons? Thanks.


The advantage of the 6000 or 8000 stones is, now that you HAVE a sharp chisel, you can go use them after use, TO KEEP IT SHARP (just removing the burr).

As you have seen, lot's of methods can be used. The trick is getting good, at one your comfortable with.

[Wilbur Pan]

One of the things that should be remembered when comparing/contrasting different sharpening systems is that the grit sizes from one system to the next don't exactly correspond with each other. For example, a hard black Arkansas stone is equivalent to 2000 grit sandpaper that the Scary Sharp system uses, and 6 micron Dia-paste. All of these fall in between the 2000 and 4000 Japanese waterstones.

This is because the fineness of a sharpening agent really depends on the size of the grit particles being produced. In the above example, the hard black Arkansas stone, 2000 grit sandpaper, and the Dia-paste all make particles that are 6 microns in size. The Japanese 2000 grit waterstone makes a 7 micron particle, and the Japanese 4000 grit waterstone makes a 4 micron waterstone.

Once you look at things in this light, seemingly huge jumps in grit number become much less impressive. Going to a Japanese 8000 waterstone means dropping down to 2 micron particles, and the fabled 16000 waterstone gives you a 1 micron particle.

So the question is whether or not 4, 2, or 1 micron particles make a difference in the edge. I have heard many people who are advocates of oilstones and stropping with green compound question the wisdom of going to as high as a 16000 Japanese waterstone, since going beyond 4000 seems like a waste of time.

Well, as it turns out, the grit size of green compound is 0.5 microns, which is even finer than the 16000 waterstone. So if one agrees that stropping with green compound is a good thing, then going to a 16000 waterstone is a good thing as well.

Of course, the bottom line is that if you get an edge sharp enough to do the woodworking you want, then that's all that's important.

[Derek Cohen]

Wilbur

Good information.

One of the terms used in honing that I consider misleading is "sharp" or "sharper". I prefer to use the term "smooth" or "smoother". In other words, when we work our way to smaller and smaller microns, the edge of the blade is becoming increasingly smoother. What is in fact occuring is that the serrations are becoming smaller. Taking this a step further, the smaller the serrations, the less there is to break off, and the longer the blade remains smooth/sharp. Conversely, the more or larger the serrations, the greater the likelihood of serrations breaking off, and the shorter the edge will remain "sharp".

In summary, the finer the grit/lower the microns to which you polish an edge, the longer that edge will be held.

The latter is my inference and I have not seen or read quantifiable evidence in support. I like the logic and choose to support this idea.

Regards from Perth

Derek

[Bob Smalser]

...a grinder with a coarse grey wheel, and a small $7 Buck Knives Arkansas stone, and put an edge on the chisel that was able to shave hairs off of my finger.

You can shave hair with a pretty ragged edge, but that edge often won't cut smoothly and won't hold up in use, especially if its hollow ground. The striations in a ragged edge are prone to chipping easily.

Everyone needs some sort of grinder, although a belt sander with 60 grit held upside down in a vise will work fine with frequent water dips. Just be sure to blow all the sawdust out of it first so it doesn't catch fire, eh? But unless you are rehabbing abused tools, you can learn to hone so you'll never need the grinder again for that rehabbed tool unless you drop it or hit hardware and it chips. Grinding often takes off more than absolutely needed, shortening the life of the tool.

After the grinder you need a minimum of a coarse stone, a fine stone and something to strop with. I'd recommend 3 stones, coarse, medium and fine to save wearing out your fine stone, and if you already have that grinder, nothing I know of strops as well and as fast as green rouge on a stitched muslin wheel. The felt wheels like to burn, so I'd avoid them starting out.

The stones can be water stones or oil stones. Water stones work faster than novaculite but wear hollows quicker, requiring frequent flattening and shortening their lives. Oil stones are either carborundum or India composite stones or natural Arkansas (novaculite) stones. Carborundum and India stones cut just as fast as water stones but also wear hollows just as quickly. The novaculite stones are very expensive but the hard ones literally last for generations.

http://pic20.picturetrail.com/VOL12/1104763/17020258/272093964.jpg

I use Carborundum for my coarse stones, and novaculite for the rest with a few India stone rounds in coarse and fine. A kerosene or mineral spirits bath isn't necessary, but keeps them a bit cleaner. The carborundum and India stones are relatively cheap and save wear on the soft novaculite stones removing grinder marks. I generally stop at "hard Arkansas" but sometimes I go to "black Arkansas". With a hard, green rouge strop afterwards, frankly it's hard to tell the difference between them so going beyond with even finer stones holds no interest for me.

So you don't need them all at once, but you do need at least two. You can sharpen gouges and other odd shapes with sandpaper wrapped on a dowel or fitted wood block to start with. You'll progress faster if you let your sharpening skills grow with your woodworking skills instead of the other way around. In my pic you're looking at a 80-year collection from 4 family woodworkers across 3 generations.

[Sean Kinn]

Thanks everyone, I appreciate all the different approaches. I'll likely start out with the scary sharp sandpaper approach, since I already have all of the paper from another project. I'll see how that goes, then decide how I want to dive into the stones.

[Jim Nardi]

You need to figure out which method will work for you. He's likely spent a bit more time flattening the backs of those chisels then he's letting on. I agree that it take some time and practice to master a electric grinder but not years. Perhaps a hour or two after you get it setup. Which means to me making a base for the grinder, getting the stone round and vibration free. Magic marker to see where your grinding. Something to practice on. A cheap square is also of some use. Personally I'm not into dipping anything into water when grinding. If it's to hot to hold between your finger and thumb your grinding to quickly.

[Derek Cohen]

.. I've read all sorts of articles here, and on other sites that have you using 4-6 different stones to sharpen up a set of chisels. ...


Sean

Let me know what you think of this article I posted here a while back:

http://sawmillcreek.org/showthread.php?t=62537&highlight=cent

Regards from Perth

Derek

[Michael Schwartz]

Water stones vs oil stones is somewhat based on personal prefrence, but I prefer Watter stones because they cut faster, cut A2 steel, are messy in a different kind of way, and they don't transfer oil on your tools and hands that will effect finishes.

A strop with .5 micron green compound is a good follow up to a fine arkansas stone.

A good all arround kit on a budget

Float glass, 60,100,150, and 200 grit sandpaper
Medium/fine double sided diamond stone
Combination 4000/8000 grit water stone
Leather strop, and .5 micron Green Rouge

This will provide you all you need to flatten out the backs of chissles and plane blades, and grind the bevles (the corse sandpaper and a honing guide) The Diamond stones will begin to hone the backs and the bevles, and will also flatten out the water stone, and the combo water stone will hone and polish to a really good edge. The stop will finish that off and maintain the edge as you use that tool so you can keep it fresh.



Here is what I use

Sandpaper under 220 grit
Corse, medium, and fine diamond bench stones (fine = 1200 Mesh)
Norton Combination watter stone 4000/8000 grit.
Leather strop with .5 micron green rouge (Veritas) for chissles and a peice of hard maple with the .5 micron compound for plane irons.

[Jake Darvall]

you don't need stones at all, if you really want a chisel fast. Just grind the bevel to burr off AlO wheel, and buff tip to kick burr on hard felt buffing wheel charged with green compound.

[Steve Rybicki]

to burr off AlO wheel, and buff tip to kick burr

I need a little help interpreting this. What is "AIO"?

[Bruce Haugen]

I need a little help interpreting this. What is "AIO"?

Steve,
I think it's A / O, not AIO, and I believe it stands for aluminum oxide.

Bruce

[Marcus Ward]

Al (aluminum) O (oxygen - oxide).

[Jake Darvall]

sorry. yes. aluminium oxide.

Just the kind of wheel that friendly to your blades. Its make grinding practical. The wheels that come with grinders normally, glase over quickly.....grind slowly with few sparks, and blue your tool before you know it.....

[Bob Smalser]

you don't need stones at all, if you really want a chisel fast. Just grind the bevel to burr off AlO wheel, and buff tip to kick burr on hard felt buffing wheel charged with green compound.

If the lads think they can burn their hard-earned edge away using a grinding wheel, wait til they try an 8" hard felt wheel on a high-speed buffer grinder. Takes some practice best done using your HSS lathe tools before those expensive carbon chisels. Lotsa rouge and low speeds (if possible) to start.

[Jake Darvall]

yeh, I agree. There aggressive....but I do all my chisels that way, because its just so rapid.

When I hit the hard felt wheel, which is turning in reverse, after grinding to burr,,,, I present it heal of bevel first,,,,, then just rock it forward until you feel the hollow ground cup the buffing wheels curvature......then just lift it a touch more to buff at the tip only.

And when I sweep it across the wheel I do it with the blade slightly askew, and in one direction only to get even wear....its askew because if you plant the blade directly on the wheel like you do on the grinder the very corners of the blade can round over....

sounds tricky, but its quite reliable and fast..........mind you, I only do it with chisels and profile blades. With bench plane blades I use the stones.