Experiments on Knife Sharpening John D. Verhoeven ... - BushcraftUK

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significant difference in the two processes, aside from ease of use, is the time intervalbetween contact with the steels on the right and left faces of the blade.Conclusions1 These experiments confirm the recommendation of Juranitch [2] that optimum edgeformation in the steeling process requires the use of only a few strokes at a light pressure.Using more than 2 back and forth strokes led to a roughing of the edge by break-off ofledges along the edge of the blade.2 The steeling process does not offer an improvement in edge quality with respect toedge straightness, edge roughness or edge width over that obtained with the fine 1000 gritTru Hone wheels, and is slightly detrimental.3 With 600 grit aluminum oxide wheels (and presumably with coarser such wheels) thehoning does produce a dramatic improvement in edge roughness and straightness and asmall improvement in edge width, from around 2-3 µm to 1.5-2 µm.4 The SEM micrographs show that the action of the steeling on the 600 grit blades is oneof wrapping the bur formed by the wheels around to one side of the edge and deformingit up against the face. The net effect is a slightly straighter edge with significantlyreduced roughness in face views and a more uniform and slightly thinner average edgewidth in edge views.5 With the 600 grit blades no significant effect was observed for changing the steeling 2βedge angle from 50 to 70 degrees on blades with an as-ground edge angle of 39 degrees.6 The work on the 1000 grit blades that showed ledge breakout with increasing numberof passes presents strong evidence that the edge of the blade is very susceptible tofracture as well as plastic deformation in the steeling process. This conclusion is quitereasonable when one realizes how thin the blade is right along it edge.16
7 All of the blades that were studied here had a 2β edge angle of close to 40 degrees. Inblades where the edge angle is reduced to lower values, like 20 or 30 degrees, the stressesproduce by the steeling process at the edge will be higher due to the thinner edge widthsbelow the outer edge. It is likely that to avoid edge breakout along the edge in thesecases steeling would require only a couple very light strokes, with a 2β edge angle of nomore than 10 degrees above the as-ground edge angle.8 It also seems likely that the hardness of the blades might have a significant effect onthe occurrence of edge breakout during steeling. Hardness values above HRC = 60would increase the occurrence of breakout above that found here, and values below 60would decrease occurrence.17
Page 1 and 2: Experiments on Kni
Page 4 and 5: as a guide to good sharpening techn
Page 6 and 7: machine ground. The final 2β edge
Page 8: [2] Experiments wi
Page 11 and 12: Even on freshly dressed wheels a 2
Page 13 and 14: ledges of material has broken out o
Page 15: at the 2β edge angles of 50 and 70
Page 19 and 20: Japanese waterstones plus leather s
Page 21 and 22: Figs. 23-24. The blade of Fig. 25 w
Page 23 and 24: Figs 23 to 26. It appears that the
Page 25 and 26: [5] Experiments wi
Page 27 and 28: the 2β target hone angle set to ar
Page 29 and 30: lade of Fig. 33 along part of the l
Page 31 and 32: 3 Dropping the 2β edge angle from
Page 33 and 34: the 600 grit wheels were largely re
Page 35 and 36: seen that the buffing action is rem
Page 37 and 38: [7] Experiments on
Page 39 and 40: found that the softer steel produce
Page 41 and 42: optimum EW values found for afinal
Page 43 and 44: [9] Summary and ConclusionsThese ex
Page 45 and 46: 6 When the 2β edge angle is reduce
Page 47 and 48: Appendix 1Edge angle measurements w
Page 49 and 50: β = arc cosine((R 2 +L 2 -Y 2 -h 2
Page 51 and 52: YY = 45.5 mmLThese parameters can b
Page 53 and 54: Appendix 3The Tru Hone Sharpening M
Page 55: To overcome this problem withgrindi

Experiments on Knife Sharpening John D. Verhoeven ... - BushcraftUK

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