Revision as of 06:40, 7 June 2020 (edit) imported>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...")		Revision as of 07:12, 7 June 2020 (edit) (undo) imported>Stever No edit summary Newer edit →
Line 2: Starting Point: Shape of knife already done and rough bevel created This page is not finished and are just rough notes based on the [[Workshops/bladesmithing\|bladesmithing]] workshop ===General Notes==== ~~Can~~Blades ~~sharpen~~can be sharpened with an included angle anywhere from 7 degrees (razor blade) to 45 degrees (axe head). Finer edges are sharper but weaker so they dull faster, wider edges are less sharp but much more robust and will last much longer before resharpening. ~~Sharpness~~Desired sharpness depends on what you're cutting, not much point going above 1000/1500 (and strop) with wood *400-1000 grit stones are for grinding of the blade, rough shaping to get the edge to the right angle and depth All Stones used wet- to aid lubrication and cleaning off swarf▼ 1000-3000 grits are for sharpening, actually putting the edge on the blade 3000+ grits are for polishing, smoothing out scratches in the edge so it won't catch *10000+ grits are final mirror polishing to things slide off the blade Note on grit grades, not all 1000-grit stones are equal. Stones made from a hard material (e.g. diamond) will behave as if they're coarser than the grit number would suggest, stones made from a soft material (e.g. F3 stone) will behave as if they're finer than the grit number would suggest ▲All Stones used wet- to aid lubrication and cleaning off swarf, use spray bottle to regularly re-wet while using. Water stones: kept permanently submerged in water. Line 12 ⟶ 19: 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. F3 stones don't need soaking but still need to be wetted regularly while in use. Both Water and English stones need even more care on push stroke to prevent nicking stones. ===General Process=== Choose an angle and hold it as stable as you can. Can be helpful to move entire upper body rather than just arms. Do not "Roll" the knife over the stone. Angle might get slightly steeper as you go up the grits if you're aiming for a prismatic grind but is usually constant. 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 Clean stone thoroughly under running water after use. For diamond stones dry them carefully, others can be put away damp. 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. Line 23 ⟶ 33: ===400 Grit Diamond Stone=== Coarse shaping of the cutting edge, blade is un-usable at this stage Result under microscope: Dull with obvious scratches Can feel burr with finger ===1000 Grit Diamond Stone=== Finer shaping of cutting edge, edge is coarse and serrated and will rapidly dull if used 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=== Starting to sharpen the edge, edge is getting smoother and sharper, burr will still cause problems in softer materials Result under microscope: Bright silky matt, little scratching Repeat process - likely trouble to feel burn with finger ===3000 English Stone=== Fine sharpening of the edge, edge is now very sharp and should be reasonably stable. Result under microscope: Shiny, no scratches Burr probably too small to be felt ===4000 F3 (triple fine) Water Stone=== Polishing the cutting edge, razor sharp at this point and usable even in quite soft materials Use only light pressure on both strokes Result under microscope: Shiny but reflective, matt mirror Burr too small to feel, have to judge when to stop based on experience and microscope Often stop here, apart from stropping▼ ===8000 English stone=== ▲Often stop here, apart from stropping Not normally needed, will put a fine polish on the edge ~~Could continue to repeat process with 8000 stone~~ Result under microscope: Visible shine to cutting edge across whole blade Burr too small to feel, have to judge when to stop based on experience and microscope ====Stropping 30000 grit==== ~~Done~~Puts toa mirror polish on the edge to help, to help item being cut slide across blade. Result under microscope: Definite shine, like mirror Only pull strokes on leather strop, 30/40 on each side with stropping compound Hard-backed strops make it easier to hold proper angle, flexible strops will round-over the edge if not used very carefully ===Time Taken==== 30 mins for 4000 grit, 10 mins for each after that ~~Highend~~High-end tool steel - double numbers above Very high grade (e.g. D2, CPM140) - 6 hours total ==Resharpening Blade== Minor touch-up's can be done with just the strop which will remove burrs but leave nicks and chips ~~Minor touch up- strop~~ * Otherwise start at 1500/ 3000 * Back to 400 grit only if there's large, clearly visible damage to cutting edge

Techniques/sharpening: Difference between revisions

Techniques/sharpening (edit)

Revision as of 07:12, 7 June 2020