By Roy Bloom, CJF APF-I
The following is a method for knife sharpening that I have been using for some years. You may be able to use this method to improve your knife’s cutting ability.
It is important that you maintain a thin blade. The thicker the blade, the larger the bevel at the cutting edge. If the blade is thick, you have to use too much pressure to pull the blade through the cut; the thinner the better. A fine bevel is easier to maintain and offers less resistance, allowing the knife to cut easily. Pay attention to the size of the bevel on a brand new knife and try to maintain that size throughout the life of the knife. As you sharpen and use your knife, the width will decrease and as it decreases the edge will thicken. The blade will need to be thinned.
In photo (1) I am thinning the blade. I have taken a belt and cut it about 1/2″ in width. You can do this with any belt. Cut the back with a razor blade about 4″ and carefully tear the rest. With the edge pointing up, so you can see the bevel and not get too thin, grind the knife to the desired thickness. Don’t let the blade get hot. If you see any color you have gone too far, too hot. Keep the blade cool by dipping in water after every couple passes. Use a new belt if possible, 100 or 120 grit. A new belt will cut quickly and the dipping of the knife in water will not allow the blade to heat up.
If your blade’s width gets down to 1/4″ throw it away. When the blade gets that thin it can break easily and that’s when you find it in your leg or wrist.
Now that I’ve thinned down the blade I need to establish the bevel. Photo (2) shows different makes of diamond hones. You want one that fits the hook size of your knife. Work the bevel into the hook (photo 3) and then the blade (photo 4). Some knives are made of a soft enough material that a small rat tail or triangle file can be used. Using files is good for serious roughing in but it produces a serrated edge, which is not desirable. If you start with a diamond hone you may never need a file.
Now that the bevel is established I go to the Scotchbrite wheel. This is a medium grit Scotchbrite. I have found this to be best for cutting quality. In photo (5) I am cutting a groove in the edge of the wheel. I have braced a rat tail file to cut the groove. The groove will allow me to thin and sharpen the hook. Using the Scotchbrite wheel, I can polish the whole blade and the bevel. You want to maintain the angle of the bevel through all the stages so pay particular attention to how you hold the blade to the wheel. Make sure the edge is down, otherwise your knife may become a permanent fixture in your forehead. Start with the hook (photo 6) and sweep through the blade (photo 7), always maintaining the angle of the bevel.
Now for the final polish. I use a medium felt wheel (photo 8) with the same groove cut in its edge as I put in the Scotchbrite. Apply green rouge to the groove edge and face of the wheel (photo 9). Use the same method as on the Scotchbrite so you can maintain the bevel angle and make as many passes as necessary to polish the edge (photos 10, 11).
Once you have achieved sharpness with the felt wheel the edge should last a long time, assuming you are using your knife carefully and cleaning the hoof. When your knife becomes the least bit dull, touch it up on the felt wheel. You should not have to go through all these steps again until the bevel gets too large. When it does just repeat these steps.
Many of the suppliers carry the various wheels, tools and materials you need for sharpening knives. If your supplier doesn’t carry them have them contact Bloom Forge or FPD for info on where to get them.
Roy Bloom, CJF APF-I
Roy Bloom has been shoeing horses since 1973. He has been a member of the American Farrier’s Team on two different occasions and for many years served as the manager of the team. Roy has always been willing to share the extensive knowledge he’s gained over the years with members of the farrier industry. In addition to his farrier background, he developed a strong interest in blacksmithing and tool making and for many years has been manufacturing a broad range of farrier and blacksmith tools. He also has a fully equipped shop and the ability to do a wide variety of ornamental and artistic work. Roy’s work as a clinician has earned him the Educator of the Year Award from the AFA and a position in the Horseshoer’s Hall of Fame.