Knife sharpening can be a challenge, at least it was for me some many years ago. Once the basics are understood and the wives tales have been put to rest the task becomes simple and easy to do.
First off, an edge is simply stated as two intersecting planes at or under 40 degrees. To get a good edge the intersection needs to be clearly defined even under high magnification. Any rounding off of the edge results in poor performance.
When attempting knife sharpening one grinds the area behind the edge with a course knife sharpener or grinder at a predetermined angle until the knife sharpener reaches the new edge. At this time a burr will form on the opposite side from where you are sharpening. If you should inadvertently raise the blade to too high of an angle for even one stroke, it will ruin the edge and increase the amount of steel that you will need to remove to reach the new edge. It is common for a lot of folk to keep raising the back of the blade higher and higher on the knife sharpener to get to the edge, but this will not get you the edge you are after.
Choosing the right angle is important. If ground to steep, the edge will be useless and if ground to thin the edge will be very sharp but fragile. Most knives are ground between 15 degrees and 25 degrees from both sides with 21 degrees being the most common.. This will give between 30 degrees and 50 degrees total angle with 42 degrees the most common total angle.
Hoof knives are sharpened from one side only. I suggest that you sharpen the blade at the same approximate angle that it come to you new, about 25 to 30 degrees, but don't be afraid to experiment a little with the knife sharpeners because circumstances can vary and what works for one may not work for all. As you can see consistency is far more important than obtaining the precise angle and using any kind of guide to prevent going to high is of great use.
Another point to remember is the finer the grit used with the knife sharpeners to grind the final edge angle the sharper the edge. I mentioned above that grinding in the bevels produced a burr. This burr will get smaller and thinner when you use the finer stone and will buff of easily.
In summing up, grind in the correct edge bevel until a burr develops with a course stone, using if at all possible some devise to maintain the same angle from stroke to stroke. When the burr forms change to a fine stone and remove the scratches from the course stone. This will give you a very sharp knife. If you want a better edge use a finer stone yet and buff or strop the edge to remove the final burr.
Belt grinders and buffers are very inexpensive and with practice you can produce very sharp knives in very little time. If you're a professional farrier it would be worth your while to learn how to use one efficiently. Practice with old junk knives until you get the hang of it. The two things to remember is don't over heat a blade and be very careful. Ask your self, where will the blade go if it catches on the belt or gets between belt and wheel. If belt grinding your blades is not your cup of tea, then check out the Edge Pro sharpener. It is a very precise sharpening instrument and with some modification will sharpen hoof knives.
Using a narrow strip of abrasive 120 grit belt about 30 inches long folded and glued back to back so that both sides are abrasive. Fasten one end to a solid holder about head high and drag the hoof knife down the belt with one hand while holding the belt taught with the other hand. This will do as good a job as any on the hoof knife and is not hard to catch on to. Follow up with a finer grit belt and buffer.
You can visit my other web site for more information about knife sharpeners or knife sharpening.
For additional information on knife sharpening check out these sites.
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