Sharper Than Razors sharpening detailed

Nice post, pics, and results on the Reate. Thanks for sharing your sharpening process in detail and taking time to document it, super interesting!

Do you ever get tired from swapping out Tormek wheels? :D
 
While it's well worth the trip over to the thread that wootzblade linked to... I wrote myself a brief summary that I thought I would add here...


Knife Grinder’s “Sharper than Razor” sharpening summarized…

Knife: M390 steel at 20° per side… reprofiled and sharpened to 12° per side.

  • Pivot oiled / Handle wrapped with cling wrap, both to protect pivot... (good choice… I too like cling wrap better than tape).
  • Knife set in Tormek jig (see post for more specific info).
  • Bevel shaped & edge set on CBN wheels to 12° per side… finished on 1000g CBN
  • Edge refined on diamond charged paper wheels at 11.9°... 0.1° less than edge angle. (Narrows the edge on the sides). 5µ and 2.5µ paper wheels.
  • Debur on rock-hard felt wheel w/ 1µ diamond… back at 12° angle. (Remove “feather” burr).
  • Hone on paper wheel w/ .5µ & .25µ diamond compound… 12° angle.
  • Debur on leather wheel w/ .25µ diamond & CHROMOX (.3µ?) mixture. 12° angle. (Remove “foil” burr).
Good stuff! :thumbsup:
 
Yeah, that is the protocol exactly as in our books. The only one word I would change in the 2nd step to stress its importance:
Knife centered in the Tormek jig.

Edge sharpness BESS scores along this sharpening:
...
  • Bevel shaped & edge set on CBN wheels to 12° per side… finished on 1000g CBN
    325 BESS
    a one-sided burr is present - the sharpness score is deceitfully worse than the original because of that
  • Edge refined on diamond charged paper wheels at 11.9°... 0.1° less than edge angle. (Narrows the edge on the sides). 5µ and 2.5µ paper wheels.
    After the 5µ paper wheel - 80 BESS;
    After the 2.5µ paper wheel - 75 BESS
    virtually the same sharpness reading, and may score closer to 100-125 BESS - readings at this step are misleading because of the micro-burr; it is not the edge sharpness, it is the micro-burr playing.
    HERE lies the key to success - hone on finer grits at an angle shallower than the edge angle, and make sure some remnants of the burr are still detectable by palpation and maybe even by the naked eye at this stage.
  • Deburr on rock-hard felt wheel w/ 1µ diamond… back at 12° angle. (Remove “feather” burr).
    50-60 BESS
    a true razor edge exposed
  • Hone on paper wheel w/ .5µ & .25µ diamond compound… 12° angle.
    35-40 BESS
    sharper than razors
  • Debur on leather wheel w/ .25µ diamond & CHROMOX (.3µ?) mixture. 12° angle. (Remove “foil” burr).
    25 BESS
    Final sharpness along the edge scores from 15 to 30 BESS, the exact readings from the blade heel to the tip are: 15 - 15 - 25 - 25 - 30
    This is twice sharper than standard DE razors, and the same sharp as the best Feather DE razor.
Curtis, my friend, in the end we've got such good a summary, that with your permission I will add it to my original post on the Australian forum.

The above protocol has proved successful on many knives, but variations are possible.
E.g. insted of the CBN a diamond wheel or plate can be used;
or to deburr, instead of the rock-hard felt you can use a different substrate, what matters is that this substrate should be more pliant, more compressible than what you honed on in the previous step.
 
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