Sharpening on wet & dry SiC paper

[kwakster]

User Fallkniven A1 Pro in CoS stainless steel @ ~60 HRC from an experienced Dutch hunter, with it's apex at ~30 degrees inclusive.
The factory edge reflected light from slow wear, no dents or chips, and the owner wanted the new edge to have a somewhat toothy apex.
Pulled the edge a few times very lightly over a Chinese 3000 grit diamond plate, this to remove the weakened metal in the old apex and create a very narrow and continuous light reflection all along the edge.
I use this line as a guide to sneak up upon while sharpening, and in the end make it disappear as evenly as i can.

Sharpened the partially convex sides of the blade by hand to a new apex with an ever so tiny burr using only 1000 grit wet & dry SiC paper on a semi-hard rubber backing with WD40 as a lubricant, while regularly checking with my Tormek WM200 AngleMaster to make sure that the newly forming apex would also become ~30 degrees inclusive.
When this was done i removed the tiny burr with some careful light stropping on a piece of hard cardboard with a bit of 1.0 micron mono-diamond paste.
The sharp diamond particles are very efficiënt in removing tiny burrs on high alloy stainless steels, while the hard cardboard has just enough give to make sure that most of the toothyness in the apex from the 1000 grit wet & dry remains.
The new apex is just keen enough to pull a chest hair taught from root to tip and sever it close to the point of holding.

Took a number of pics with part of the camera & my finger in them on purpose to give a better idea of the scratch pattern.
You can click each picture 2 x for more detail.

[kwakster]

Spyderco Stretch laminated blade with HAP40 core @ 63-64 HRC and an edge measuring between 25-30 degrees inclusive from the same owner as the A1 Pro in my first post.
The old & a bit pitted apex was removed on a Chinese 3000 grit diamond plate to create a very narrow and continuous light reflection all along the edge, then the blade was thinned by hand using 1 full sheet of 400 grit wet & dry on a semi-hard rubber backing with WD40 as a lubricant, right up to the still flattened edge, and then refined & apexed to an ever so tiny burr on 1/2 sheet of 1000 grit wet & dry on the same backing with again WD40.
The burr was then carefully stropped off on a piece of hard cardboard with a bit of 1.0 micron mono-diamond paste.
The new edge measures ~20 degrees inclusive and is reverse chest hair whittling sharp with just a bit of tooth.

Before:



After:

[Gerhard Gerber]

Oooooooo that Stretch! 

[kwakster]

Just finished hand regrinding this older ScrapYard Wardog in INFI steel using wet & dry SiC paper, first on on glass then on rubber with WD40 oil as a lubricant.
The old convex edge measured ~40 degrees inclusive at the heel widening to ~50 degrees inclusive at the belly, while the new convex edge measures an even ~30 degrees inclusive from heel to tip.

Blade crosshatched with a red marker, which i find useful to see where exactly i'm removing steel in the beginning.
The apex has been removed by pulling the old edge a few times very lightly over a fine diamond plate.





The almost 6 mm thick INFI blade:



After hand regrinding the blade on 1/2 a sheet of 180 grit SiC to a shallower convex edge (without producing a burr), while regularly checking with the Tormek AngleMaster to make sure that the new apex would fit in the 30 degrees inclusive slot.
Time spent up to this point: 2 hours





After the first refining steep on 1/3 of a sheet of 240 grit SiC, this time creating a small and even burr (only when the grit became increasingly finer due to SiC's friable nature)





After refining the scratch pattern and the burr on 1/2 a sheet of 400 grit SiC, but now on a semi-hard rubber backing, again using WD40 as a lubricant.
The burr has already been removed on the Tormek leather wheel with 1.0 micron diamond compound to reveal a toothy edge that is reverse chesthair whittling sharp.



Specs:

Overall length: 24,5 cm
Blade length: 12,2 cm
Max blade thickness (ricasso): 5,98 mm
Steel: INFI
Hardness: 58-60 HRC
Handle material: Resiprene-C rubber
Weight: 176 grams

[kwakster]

Personally i like the contrast of that thick blade with the narrow edge angle.
It will of course never be the greatest slicer, but it will definitely make a sturdy & dependable hunting / survival knife.

[Aloha]

  that came out wonderful.  I like the crosshatching you did to begin smart move.  Nice to get that even 30 inclusive the length of the edge from where it was.  Not familiar with the steel off hand but I'm sure it'll be ready for new adventures with a new edge.