Techniques/sharpening

Knife Sharpening - An aide Memoire

Starting Point: Shape of knife already done and rough bevel created

Can sharpen anywhere from 7 degrees (razor blade) to 45 degrees (axe head)
Sharpness depends on what you're cutting, not much point going above 1000/1500 (and strop) with wood
All Stones used wet- to aid lubrication and cleaning off swarf
- Water stones:
  - kept permanently submerged in water.
  - Only use water. Certain stones can be used with oil but then can never be used with water again.
  - Water stones may not be completely flat from previous use (dished). Can flatten with 400 Diamond Stone
- English stone can be kept dry but needs to be soaked in water for half an hour before use.
Both Water and English stones need even more care on push stroke to prevent nicking stones.

Firm Pull stroke on stones, very light push stroke (to prevent nicking stones)
Should only have to do 400 Grit when first shaping edge, unless you've badly nicked the blade
Clean Knife between grits - otherwise previous swarf can scratch blade - water and wipe
Alternate both sides until there's a burr one side all along blade that can be pushed to the other side. Can feel burr with finger
Then do 10 strokes on one side, then the other. Then 9 strokes on each side... repeating down to 1 stroke.
Repeat for each grit

Result under microscope: Silky matt consistent across bevel with less obvious scratches
Repeat above process, can still just feel burr with finger

Often stop here, apart from stropping

Could continue to repeat process with 8000 stone

30 mins for 4000 grit, 10 mins for each after that
Highend tool steel - double numbers above
- Very high grade (e.g. D2, CPM140) - 6 hours total

Minor touch up- strop Otherwise start at 1500/ 3000