Photos Sharpening on wet & dry SiC paper

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kwackster

Joined
Dec 23, 2005
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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.









 
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:









 
I'm impressed by your dedication to 1000 grit paper. That's like what, 4k jis? Must've taken forever!
 
Actually i only used 400 grit and 1000 grit SiC paper on the Spyderco Stretch, but in total it was almost 3,5 hours of work.
 
Recently acquired this venerable old Buck 110 no-dot (1972-1974) which had a rounded point, no edge, and a handle filled with crud.
Cleaned everything with tootpicks, an old tootbrush with diluted detergent, and lastly an ultrasonic cleaner, polished the brass, then reground the blade by hand using only 400 grit wet & dry paper with WD40 as a lubricant.
The new convex edge measures ~25 degrees inclusive and there is a new point too.

















 
Just finished hand regrinding this older ScrapYard Wardog in INFI steel using wet & dry SiC paper, first 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 step 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)





Busy 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 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
 
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Well done Sir! I have an array of knives that see nothing but harbor freight SiC paper. They are inexpensive knives and I can put a toothy edge on in no time. I have a piece of oak, 2 actually, with fine, and extra fine affixed. I keep them in the kitchen and I use it all the time. Although my usage is quick and dirty compared to yours Kwackster, the fact remains that for under 10$ I can buy a pak of coarse/fine/ and xtra fine SiC paper.
With the addition of a strop of sorts you could do a reasonable job maintaining MOST knives.
Then I look at the all the stones, plates, and various equipment I have and laugh.
I love Bladeforums but it sure has cost me a LOT of cash.
Great thread Kwackster, sandpaper deserves a bit more respect than it gets, it can do a lot more than remove surface rust.
 
mycough mycough : and that's why i started this thread, to showcase that sharpening/reprofiling/regrinding doesn't have to cost a lot of money.
If you're willing to put in some time & elbow grease the results can be quite satisfying, and will only set you back a couple of dollars.
I even save the already used & oiled SiC paper for touch-up jobs on a later date.

Personally i like the contrast of the Wardog's 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.

 
N now : Happens every full moon, runs in the family i'm told, :D

It's just a quick test for myself to see if i did things right.
When i think i'm done deburring i cut off a chest hair and try to whittle it from hair root to hair tip, while holding the hair at the root end only.
When this succeeds i whittle a few slivers from an old piece of beechwood cutting board or make a few firm cuts into the side of a polyethylene cutting board.
After this the edge should still be able to whittle the hair in exactly the same manner, and the further away from the point of holding i can whittle the hair the keener the apex is.
There's also a noticeable difference in how coarse & polished edges do this test.

This thread might be interesting: https://www.bladeforums.com/threads/hair-whittling-sharp-how.1584201/#post-18095741
 
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