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Revision as of 06:40, 7 June 2020 by Stever (Created page with "==Knife Sharpening - An aide Memoire== Starting Point: Shape of knife already done and rough bevel created ===General Notes==== *Can sharpen anywhere from 7 degrees (razor...")
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.
- Water stones:
- 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
400 Grit Diamond Stone
- Result under microscope: Dull with obvious scratches
- Can feel burr with finger
1000 Grit Diamond Stone
- Result under microscope: Silky matt consistent across bevel with less obvious scratches
- Repeat above process, can still just feel burr with finger
1500 Water Stone
- Result under microscope: Bright silky matt, little scratching
- Repeat process - likely trouble to feel burn with finger
3000 English Stone
- Result under microscope: Shiny, no scratches
4000 F3 (triple fine) Water Stone
- Result under microscope: Shiny but reflective, matt mirror
Often stop here, apart from stropping
Could continue to repeat process with 8000 stone
- Result under microscope: Visible shine to cutting edge across whole blade
Stropping 30000 grit
- Done to polish edge to help, to help item being cut slide across blade.
- Result under microscope: Definite shine, like mirror
- Only pull strokes, 30/40 on each side with stropping compound
- 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