The Juuma sharpening and honing stones offer a simplified working principle while at the same time ensuring the highest possible quality in the offered grits. Juuma Cobalt Blue stones are made of an aluminium oxide and a bonding agent. Adding cobalt serves to slow stone abrasion and increase the speed of sharpening. The speed bonus is especially marked when stoning blue steel (blue paper steel that is often used for Japanese planes and chisels). The cobalt gives the stones their blue colour. Juuma is our proprietary brand. Juuma sharpening stones are produced by a renowned Japanese whetstone manufacturer.
Our large selection of stones from many well-known manufacturers will allow connoisseurs to find the ideal stone for their needs. Because all manufacturers formulate their stones to emphasize a different mix of qualities, and because these qualities can vary widely between different stones, most woodworkers choose stones from several manufacturers to build up an optimal set of sharpening stones. Then again, once you get to know the characteristics of certain types of stone, you may find one supplier who will provide all the stones you need. Sometimes this can be an advantage. But there is no one size that fits all; each stone must fit your needs and work style.
In addition, the most prized of the natural Japanese Water Stones are quarried in the Narutaki District north of Kyoto, Japan and are commonly available as either bench stones or pocket stones in grits ranging from 120 to 12,000. On the other hand, synthetic water stones are made from Aluminum Oxide and commonly available as either bench stones or pocket stones as well in grits ranging from 220 to 8,000 and, although this is the same abrasive material used to make India Oil Stones, the difference between the two is that the binder that holds the abrasive together enables Water Stones to be much softer than India Oil Stones which, in turn, promotes faster cutting because the worn abrasive material breaks away more quickly and is replaced with fresh, sharp, abrasive material more quickly. In addition, because water stones do not become glazed or loaded with swarf like oil stones can, new abrasive particles are constantly exposed as the stone wears so it continues to cut consistently. Plus, they can be lubricated effectively with water (rather than oil which can ruin some water stones) which combines with the fine particles of abrasive from the surface of the stone to form a slurry which polishes the bevel as the stone cuts. However, it should also be noted that Water Stones do become uneven significantly faster than other types of whetstones although, their softness does make them easier to true again.
Manufacturer contacted and sent a new one for replacement. Great customer service but replacement item was nicked on the corner. It was still usable so i didn't bother to ask for another replacement. I would recommend item to be shipped in another box instead of an over-sized yellow envelop which is not adequate protection. Item sharpen my knife pretty good though..
Technically, the name whetstone can be applied to any form of sharpening stone, regardless of what cutting fluid is typically used with it. However because whet sounds like wet, many hear the word and assume that it refers to a stone that is used wet with water. Actually, water stones, oil stones diamond stones and ceramic stones are all forms of whetstones. So, while all water stones are whetstones, not all whetstones are water stones.
Let’s start with Arkansas. If you have heard about Arkansas oilstone, it uses the Novaculite stone that mined in Arkansas. The most expensive of Arkansas stone is the Hard Translucent model that begins to rare in the market. If you want to shop for Arkansas, they are available in different grade starting from Soft Arkansas, Hard Arkansas, Hard Black Arkansas and Hard Translucent Arkansas. The finest grade of Arkansas can shape such of mirror polishing edges.
If you do not remove enough metal to create a new edge, you will leave some of the dull edge in place. A dull blade (or a blade with dull spots or nicks) will reflect light from the very edge of the blade. A razor sharp knife edge will not show "bright spots" when you hold it blade up under a bright light. You will need to remove enough material from the sides of the bevel so that the edge stops reflecting light.
The height of the spine of your knife off of the stone below it will determine the angle. A typical sharpening angle for a typical chef knife is 19 or 20 degrees per side. For the sake of removing confusing obstacles that could hinder your progress, let’s just sharpen your knife at 20 degrees per side. You can determine exactly how high off the stone that knife should be held by measuring the height of your blade at the heel and then dividing that number by 3 for a 20 deg angle.
This is a good quality stone for a beginner looking to learn about hand sharpening knives and blades. It holds up well, especially for the price point. New sharpeners are prone to gouging and scratching stones, pushing too hard, etc, and this stone handles the abuse nicely. The no slip base is very effective at cementing the stone in place, which is a critical safety feature.
Also natural stones have a random grit size that gives a long lasting edge. Basically the random grits create varying sizes of micro-serration in the blade that wear down at a different rate, therefore longer edge retention. Whether this is true or not we really like natural stone, especially for sharpening tradition single bevel Japanese knives. Use natural stones with water – it’s far cheaper than sake.
This particular silver / black sharpener is a guided sharpening tool for any professional. When using it, you'll be able to get all your pocket knives and kitchen knives to it's sharpest. There's 3 stages to it and is easily accessible to use at home. - These are the sharpening processes: coarse-grinding, medium grinding, and the extra-fine grit ceramic wheel grinder. The last one is the polisher. The blade gets polished to it's finest point. Additionally, the blade guides are interchangeable with the some of the best angles without having to guess at all those technical angles. The blade will be guided by the automatic mechanism once you lay it in the grooves. How to sharpen a pocket knife on a Presto electric knife sharpener will be effortless.