Our interview with Cliff Stamp | KnifePlanet.net
1. Hello Cliff, Can you tell us a bit about yourself, and how you started sharpening knives?
[box size=”large”]My grandfather showed me the basics when I was very young, ~ 5 . [/box]
2. Can you tell us more about the sharpening technique that you use today?
[box size=”large”]I currently use a modified 3-step and plateau sharpen. This means the process is basically :
– grind the apex back to remove any fatigued metal if necessary, ensure the edge follows the right/smooth curve
– grind the edge bevel until it almost forms an apex but not quite (this is the plateau part)
– grind an apex bevel to finish
This sharpening wastes no metal in sharpening, and produces the strongest edge.[/box]
3. Do you strop your knives on leather or another medium upon completion of your sharpening process and if so, why?
[box size=”large”]No, it would not do anything productive. The knife is sharpened on the stone so stropping could only degrade the sharpness.[/box]
4. How do you test your knives for sharpness?
[box size=”large”]I measure it by push cutting fine thread and measuring the force, and slicing fine thread under a given tension and measure the distance of cut.[/box]
5. What do you think is the most important Water Stone in your line up?
[box size=”large”]All stones work well on certain steels under certain pressures. My most common heavy grinding stone now is a Suehiro ‘Chemical‘ 320 because it works well under low to moderate pressure (< 5 psi) on easy to grind steels . On harder to grind steels (10V) it needs more pressure (10 to 15 psi) and it tends to smooth out in use and have to be conditioned. For those steels I would use a Sigma Power II which has a lower bond strength and will cut them and stay aggressive at low pressure (< 5 psi).[/box]
6. How do you flatten your water stones and how often do you do this?
[box size=”large”]All of the stones including Norton’s are flattened on other stones, this keeps everything flat. They are flattened as soon as they show any visible deflection, and they are conditioned when they go slick. How long this takes depends on the steel and pressure. But it is usually between 1000 – 5000 passes.[/box]
7. What do you think is the most common mistake beginner knife sharpeners make, and how can they avoid it?
[box size=”large”]The most common problem isn’t really with the user but with the knives. Most production knives and even the small shop blades have very uneven edges. If you are starting to sharpen and the angle on one side of the edge goes from 15 to 20 dps and on the other side ir goes from 20 to 25 dps it will be frustrating.This is where coloring in the edge can help as it will show that you are only grind on part of the edge on one side and maybe another side isn’t even grinding on the edge at all.
Beyond that, the most common mistake is just trying random things instead of thinking about what you are doing and how it is achieved. For example you find someone using the Sharpmaker and going through all the stones, not having success and then trying it again, swapping the corners for the flats, trying the 15’s and then the 20’s. Basically all the things they can think on . This is likely to make for a very frustrating time. Instead use the basic three step method and once it is mastered look to things like plateau sharpening, and experiment with various angles, grits types of stones, etc…[/box]
8. Most novice sharpeners are very concerned about the sharpening angle. How do you feel about angles and their importance?
[box size=”large”]It is very important to match the sharpening angle to get the cutting ability/durability you want. For sharpening, the more consistent you can hold an angle the faster (and less frustrating) the process will be. If you sharpen with a high angle scatter it will be very difficult to remove a burr and you will likely grind one unintentionally often. Hence in the beginning some kind of jig/clamp might be a good idea.[/box]
9. Is it a good idea for a beginner to start sharpening using cheap knives? Would you recommend doing it?
[box size=”large”]No, as you can learn wrong things as you don’t care about the results. Think about what you are trying to do, understand the actual physical effect that you are making and don’t skip steps or try random things. A decent beginner method is :
–cut the apex back until it forms a clear reflecting line of light
–grind one side of the edge until a burr forms
–grind the other side until the burr forms over
–increase the angle and micro-bevel using alternating and very light passes
In time you might want to not grind a bur and plateau sharpen and experiment with various angles/finishes and passes. But that very simple method can produce a result sharper than 99% of the knives made.[/box]
10. Are you still improving your sharpening process?