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Bench StonesA-13 Infill Hand Plane

Waterstone

Bench Stones:
Watter Stones VS Oil Stones

Japanese water stones have a reputation for fast and efficient sharpening. As the supply for natural stone fades away, man-made stones are becoming more available and important. Oilstones are another choice that the wood turner has, but they don't compare to the water stone's speed. One
reason that water stones out perform oilstones is that water stones are made up of soft abrasive particles that break off during use. Each stroke across the stone breaks loose a small amount of particles, constantly exposing new and sharp particles. The loose particles also build up a muddy abrasive slurry that helps to speed up the sharpening process.

Oilstones on the other hand do not have the same characteristics as water stones. Instead of the abrasive particles breaking off, they round over and become dull. At the same time, oil residue and metal particles can fill up the stone's pores, reducing the ability of the stone to produce a sharp edge.

Understanding the grit

Japanese water stone grades fall under three major groups: very coarse grits for fast removal of metal; medium coarse grits for refining the edge and removing the burr; and finish stones for the final honing and polish. These grades cover a range of 150 to 8000, and they don't exactly match up with U.S. grades. For example, the abrasive action of a 1000 grit Japanese stone is the equivalent of US 500; and the Japanese 4000, a US 1000.

In comparison to the Arkansas stones, the Japanese 800 grit is equivalent to a Natural Soft Arkansas; the 1000 to a Hard Arkansas; and the 1200 falls between the Hard Arkansas and the Black Hard Arkansas.

 

Oil Stones VS Water Stones

There are three basic types Oil Stones, Water Stones and Diamond Plates

First I will cover Oil Stones, this what I use..


OIL STONES

Crystolon - Fast cutting stones..
Premium silicon carbide abrasive..
Ideal for general sharpening of cutting tools..
Fast stock removal for quick edge shaping with minimal loading..
 
India - Norton Company's trademark for a fine finish..

Smooth cutting aluminum oxide abrasive..
Long lasting cutting edge..
The choice of artisans, craftsmen and mechanics..
Ideal for clean deburring, generating keen edges and quality finishes..

 
Arkansas - Natural stone for the sharpest edge..
Premium Novaculite quarried in Arkansas
Available in soft and hard..
 
Sharpest possible razor..
Near mirror finishes..
Use for finer honing after..

From Right to left Medium Crystalon, Medium India, Fine India, Soft Arkansas, Hard Arkansas and last is a small Medium Ceramic Stone Pictured

Norton Replacement Oil Stones
If you just getting started you can get by with just a Medium India.

Crystalon Stones
They break down very fast like Water Stones do and need to be checked for Flatness often, The Come in Coarse and Medium..
I use a Medium but think you might be able to get by without one..

India Stones
Cut well and stay pretty flat with not much need to check for flatness and they come in Medium and Fine, I use the large 11 1/2" x 2 1/2" x 3/8" thick stones from the Norton Deluxe Multistone for Woodworkers Joel is the only place I know to get the Medium Stones from at least that is what the Head of Pike-Manning N.H. Division of Norton told me.. I called asking for a Large Medium India Bench and was told that Joel just got there proto types if I wait a week they could send me three. The Medium is the first stone I would recommend for some looking to try Oil Stones Cuts very fast and leaves a very good finish. You could get away with only this stone till you wanted to expand your collection

 Arkansas Stone
Used for the final polishing to achieve a mirror finish..

Soft Arkansas (Medium) is the most popular of the grades of Novaculite. It is an all-purpose stone used by woodcarvers, sportsmen, butchers, commercial knife sharpeners and even housewives. This stone is used by people who desire keen, polished edges on their knives and tools in a minimum amount of time. Soft Arkansas stones may be white, gray and black, or pink and gray in color.

Hard Select Arkansas (Fine) is most suitable for fine polishing and the maintenance of a fine edge on knives or tools. Hard Select Arkansas is often referred to as "White Hard." However, users should be aware that Hard Select Arkansas often has color variations also. To our knowledge, this color does not interfere with the honing process by any means. Hard Select Arkansas stones are popular among woodcrafters and a variety of industries including the dental industry.


True Hard Arkansas (Extra Fine) is the finest grade abrasive available today. It is most commonly used for industrial applications where an extremely fine polish is required. True Hard Arkansas stones are often referred to as Multi-Colored Translucent; colors, both opaque and translucent, are random and may include black, red, white, and gray--often within the same stone.
 

Black and Translucent Arkansas (Extra Fine) stones are classifications included in the True Hard Arkansas grade category according to specific gravity under density standards. The reason there is a classification in this grade is because of color preferences by customers. Black Arkansas stones are black or blue-black in color. Translucent stones may be a uniform, translucent shade of gray, white, yellow, brown and sometimes even pink.


 

Oil Stone wear much less than Water Stones and only  the Crystalon  wearing enough that it  should be checked often of flatness and and lapped on a Glass or Granite Tile with Lapping Grit
The other Oil Stones about wear very little but should be check now and then and Lapped in the same manner as the Crtstalon..

Arkansas Bench Stones
For imparting a sharp edge and near-mirror finish. Use Hard Arkansas (800/900) for final honing/polishing. Use soft Arkansas (400/600 grit) for minor edge repair. Not oil filed, lubricate with Norton oil to reduce particle build-up on stone.

Some Good Reading
The Joys of Arkansas Stones


Sharpening Stone Comparison

Compares approximate abrasive
grit relationships of American and
Japanese Stones.
Stone Type US Grit Japan
 

Stone Type US Grit Japan
Coarse Crystolon, Coarse India 100 150
Medium Crystolon, Medium India 180 240
Coarse Diamond, Fine Crystolon 240 280
Fine India 280 360
Medium Diamond 320 500
Washita 350 600
Soft Arkansas 500 1000-1200
Hard White Arkansas, Fine Diamond, Medium Black Ceramic 700 1500-2000
     

 

°º¤§ Complete Abrasive Grit Sizes Chart §¤º°

This Chart lists most abrasives and there relative sizes in different formats

Diamond Abrasive Size Equivalency Chart

 

Source for Diamond and Loose Silicon Carbide Grit
Kingsley North Diamond Compounds
Better Price can be found at
Arrowhead Lapidary Supply


Water Stones

. Heavy metal removal 80 - 400 grit
. Moderate metal removal and touching up 700 - 2000 grit
. Honing and polishing 3000 to 8000 grit
 

Photo Microscopy -Natural Water Stones
Natural finishing water stones have a unique softness to the abrasive action that is not easily replicated in man-made stones. Composed mostly of quartz and Seri Cite, the particles are held within a soft bond that resembles a flaky pastry when viewed under an electron microscope. These photos are at the same magnification. The hard Arkansas and the gold stone are both coarser than the natural Japanese stone. This may not be apparent but the structure of the natural water stone permits worn particles to release in use, ensuring a consistently abrasive surface. Even though it cuts quite quickly, it produces a mirror finish because of particle fineness.
 

Man Made Japanese Water Stones

Japanese water stones are quite porous and are designed for use with water as a lubricant and flushing agent. In general, water stones should be filled with water (it takes about 5 minutes immersion) and then kept in a bucket of water or a plastic container so that they are ready for use at all times.


There are two exceptions to this practice. Natural water stones are not kept in water and the finer man-made water stones (6000x and 8000x) on wooden bases don't have to be. They can be wetted a few minutes before use, and will function well.


When sharpening with a water stone, keep the surface well wetted. The water flushes away the swarf and keeps new, sharp particles exposed for good abrasion. Just before you are ready to change stones (e.g., from a 1200x to 6000x), let the slurry build up and reduce the pressure on the tool. This slows the abrasion rate because the build-up contains smaller, broken abrasive particles and the reduced pressure further reduces the depth of abrasion. When you switch to the finer stone, you will achieve the desired finish faster.


Once again, as you approach the end of the process on the second stone, reduce the pressure and allow a slight build-up of slurry. The resultant edge will be better.


Japanese water stones tend to wear faster than oil stones - in fact, this is the secret of their rapid cutting rate. Be sure to keep your stone flat. To promote even wear, use the full surface of the stone and occasionally change the stone end for end. To true a water stone, several methods are available. A fine stone can be trued by rubbing it against a coarser one. The coarser stone should first be trued on wet-dry sandpaper laid on any true surface such as a piece of plate glass or a machined bed. 220x wet-dry paper works well.


To hold your stones in position when using them, a simple wooden jig that can be clamped in a vise or bridged across a sink or laundry tub is useful. Alternatively, a piece of rubber floor runner draped over the end of a workbench works well.

Water Stone Text above is from Lee Valley Tools Ltd.

 

Here are some tips for buying Japanese water stones.


If you need to remove a lot of metal fast, restore the damaged edge of a tool, or change the bevel on a blade, you'll want a stone in the 80 to 400 range.
For general purpose sharpening, a stone between 700 to 2000 will do the job. The finer stones, 1200 and 2000, are preferable if your tools don't have an nicks or other defects. The 800 is an good all-around choice if you sometimes need to sharpen nicked or heavily used edges.
For honing and polishing an edge, choose a stone in the 3000 to 8000 range.
Often you can get by with just a pair of stones: a medium grit stone (800, 1000, or 1200), and a finish stone (6000, 7000, or 8000). If you have to deal with damaged blades a lot, toss in a more aggressive coarse grit stone (240, 280, or 360).
Water stones can cost on average from $20 to $40, with some finer grit stones up to $80. You can often buy combination stones with a coarse grit on one side, and a finer grit on the other side for $20 to $50.
For sharpening turning gouges, there are special stones that are concave to fit the shape of the gouge.
Wet stones are better stones

The driving force behind water stones is of course, water. To keep the stones reliable wet during use, they should be thoroughly saturated before use. Soak times vary between grits. The very coarse stone stones are so porous that five minutes should be sufficient. Medium coarse stones will take about ten minutes, with the larger sized stones taking up to twenty minutes. Finishing stones are so dense that it takes them fifteen to twenty minutes to become saturated. Occasionally the slur on top of the stone might get dry during use. Just sprinkle a little bit of water on top of the stone, and that should suffice. Be careful though not to wash away the slur as it is very important to achieving a sharp edge.

The coarse and medium coarse stones, can usually be left in water so that they are always ready for use. Plastic
If you live in a cold environment take care not to store your wet stones where they can freeze. If they freeze they will be reduced to a pile of useless rubble. You'll find that your stones might take a few days to completely dry, so during that time, they should be stored in a warm environment to prevent freezing.

boxes with lids are an excellent way to store them. However, do not leave the finish stones in water. They should be stored dry. If you do store your stones in water, you will want to periodically change the water as smelly bacteria can grow, making your sharpening an unpleasant experience. The best practice for storing stone in water is to rinse them after a day's use, and store them in fresh water. This will prevent the growth of bacteria, and keep the stones from being contaminated with muddy waste containing different grit sizes.

How to flatten those stones

After repeated use you might notice that a small valley is forming in the middle of your stones, or that it's no longer as flat as it was. There are a couple of ways to restore your stones to their original flatness.

The easiest way to flatten a coarse stone is to rub it against a piece of wet/dry sandpaper. Place a 120 to 220 grit paper (depending on the flatness of the stone) abrasive side up on a piece of glass or other flat surface. Wet the sandpaper and rub the stone in a figure 8 across the paper. Check for flatness with a straight edge. Finishing stones are easily flattened by rubbing them against a previously flattened coarse stone. It is also a good idea to rub a 45° bevel on the four top edges of the stone. This will prevent "pressure flaking" on the sides of the stone.

The only way to properly flatten the very coarse 200 grit stones is to rub it on a slurry of coarse silicon carbide abrasive grit. Sprinkle a pinch of the grit on a piece of glass (6" x 18", or approximate size). Wet the stone, and begin to rub in a figure 8 pattern. Stop and check your progress frequently to prevent wasting any of the stone.

Ultimately, the best practice is to flatten your stones before or after every use. This way only a few seconds of flattening is required to keep your stones in their proper condition.

Nagura stones

Nagura stones are a useful accessory to 6000 and 8000 grit finishing stones. They serve two purposes: to develop a slurry, and to flatten high spots on
finishing stones. Creating a slurry on your finishing stones before actually sharpening your tools on them is a good practice because it will greatly speed up the sharpening process. To create the slurry first soak both the sharpening stone and the Nagura stone until saturated. Then rub the Nagura stone over your finishing stone until a good slurry has developed. If during the use of the finish stone you notice a high spot developing, you can rub it out with the Nagura stone. It should be noted that the Nagura stone is only useful with the 6000 to 8000 grit stones, they won't accomplish anything with coarser stones.

OK, lets sharpen those tools

Now that your stones are saturated with water and flat, you can begin to sharpen your tools. The first thing that you will need to do is to find a flat, stable surface to put your stones on. There are many different models of stone holders that you can buy that will do the job. You
. Heavy metal removal 80 - 400 grit
. Moderate metal removal and touching up 700 - 2000 grit
. Honing and polishing 3000 to 8000 grit


can also place your stones on your bench top on a piece of sandpaper. Or you can build your own wooden stone holder. The choice of what grit to use depends on how much work needs to be done on your tool. Begin sharpening your tool by rubbing it back and forth on the stone. A figure 8 pattern is also good to use. Allow the slurry to build up and remain on the surface. If the top of the stone gets dry, wet it down with a few drops of water. Take care not to wash the slurry away. As soon as you've developed a wire edge or "burr", change to a finish stone and complete honing the bevel and back side of the blade. Use the same sharpening technique on the finish stone as you did on the coarse stone. With the finish stones you won't see much of a burr. Let the quality of the shine at the cutting edge tell you how close you are to optimum sharpness. As you feel you are getting close to completion, apply less and less pressure with every stroke. Finish up with two or three light strokes on the back of the tool, and then a couple more on the bevel.

If your tool requires a lot of sharpening, periodically check the stone to ensure that it is flat. If not, flatten as described earlier. Using the entire stone will help to minimize any valleys or high spots from forming.

As a final step to sharpening, use a leather strop to buff and further hone the tool edge. Running the tool up and down the strop 10 or so times will do the job.

After all that, you're now ready to get down to the real work, creating beautiful works of wooden art.


WARNING: If you live in a cold environment take care not to store your wet stones where they can freeze. If they freeze they will be reduced to a pile of useless rubble. You'll find that your stones might take a few days to completely dry, so during that time, they should be stored in a warm environment to prevent freezing.
 

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Grit Equivalency Gives you a beak down of what abrasive in classes of grit so you can gauge the abrasive qualities of one to another.

Loose Grit Sharpening Blades and Iron or Flattening Bench Stones Loose Grit is a great method to use.. It is also good for extending the life of Scary Sharp Sand Paper

Diamond Equivalency Mesh sizes in micros so you can look the them up and figure about what they compare to in regular grit

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