Paper Wheel edges

[kwakster]

An older one, this user custom Andrew Demko in CPM-M4 high speed steel from a Dutch forum member.

Before sharpening:







Reprofiled from +/- 30 degrees inclusive to 25 degrees inclusive on a standard Paper Wheel with 220 grit SiC, then refined with a second Paper Wheel coated with 15 micron diamond compound, and finally deburred with a third Paper Wheel coated with 1 micron diamond compound (experimental)
The new edge survives a few forceful test cuts into my laminated test block without any visible damage (seen through a loupe), after which it effortlessly treetops the hairs on the back of my hand and slices single-ply toilet paper.
After sharpening:










Specs:

Length open: 8.7 inch (22,2 cm)
Length closed: 5.3 inch (13,4 cm)
Blade length: 3.5 inch (8,9 cm)
Blade thickness: 4,57 mm
Steel: CPM-M4
Lock type: Tri-Ad lock
Handle material: Tan G-10 on titanium liners
Weight: 214 grams

[kwakster]

This second hand Spyderco Military in CPM-D2 steel was one of the first knives i ever sharpened on my standard set of Paper Wheels back in 2009.
It had some blade play (fixed it), some discoloration on the blade (left that) and it wasn't quite sharp (fixed that with the Wheels)
Was part of my edc for several years.

[kwakster]

Did these chisel ground edges a a few years ago with a Paper Wheel coated with 15 micron diamond compound, and then stropped the burr on the other side off on hard leather with some 1 micron diamond compound.
Both knives were quite blunt, one even more than the other.
The knives are owned by two Dutch Special Forces guys who used & sharpened them while on tour in Afghanistan, and they wanted the new edges to have a little bling.

[kwakster]

Below you see 3 different viewing angles of the edge i recently put on a brand new Sebenza 25 (which had a subpar factory edge)
The owner of the knife took the pictures with a very expensive Leica camera to capture the different looks this edge type can have when seen from different angles.
For obvious reasons i named this a bling & bite finish, and it performs very well on especially high (vanadium) carbide steels.

I first reprofiled the factory edge from 35 degrees inclusive to 30 degrees inclusive with a Rubber Wheel coated with 230 grit diamond powder, then refined it with a Paper Wheel coated with 15 micron diamond compound, and lastly removed the tiny burr with a second Paper Wheel coated with 0.25 micron diamond compound.
The new and ever so slightly convex edge could treetop the hair on the back of my hand (even whittle it a bit) and easily slice single ply toilet paper.
And this was after i tested the edge with a few firm cuts into the edge of a piece of laminated desktop.

[kwakster]

I own several vintage Gerbers in M2 steel, both outdoor & kitchen models, and this Durendal slicer model from the '60's does duty in our kitchen.
Opening all kinds of paper & plastic food packages, slicing bags with espresso beans, cutting up larger fruits like melons & pineapples, slicing bread loafs and hamburger buns without crumbling, cutting sausages, etc.
Not every day, but at least several times a week.

I bought this Gerber about 2 years ago on E-Bay completely blunt, so i reprofiled & sharpened it with a SiC grit Paper Wheel, then refined the edge with 15 micron diamond compound on a second Paper Wheel, and then again with 6 micron diamond compound on a third Paper Wheel.
The tiny burr was removed with a fourth Paper Wheel coated with 0,25 micron diamond compound.
The idea was to get something of a semi-polish that would protect the exposed M2 edge better against corrosion issues during kitchen use, while still having some degree of bite.

The knife was then used for about 2 years in our kitchen, and when not in use stored on a magnet strip on our kitchen wall.
After those 2 years the edge only had a few very minor dings/flat spots in it (in the tiny belly area), but it could still shave the hair on the back of my hand on skin level quite well with about 90-95 % of the edge.
When cutting tomatoes however the edge tended to slide a bit over the skin before it started to cut.
The main reason for this kind of edgeholding is of course the fact that most of the edge on a slicer like this never touches a cutting board, only the belly area does, but the M2 steel performed quite admirably in my book.

A few weeks ago i resharpened the edge, this time only with 15 micron diamond compound, then deburred with 0,25 micron diamond compound, as i want to try the knife with some more bite.
Will have to find out if there will be corrosion issues or not.
So far i've only used it on food packaging (both paper & plastic, no fruit or other things yet), but here are a few pics how the knife & edge look now.
The edge feels sticky and is still treetopping sharp.














Specs:

Blade steel: hard chromed M2 steel
Hardness: 60-62 HRC
Handle material: cast on aluminum, chromed.
Overall length: 11.61 inch (29,5 cm)
Blade length: 6.5 inch (16,5 cm)
Blade thickness: 1,36 mm in front of the handle tapering to 0,84 mm close to the point
Thickness behind the edge: 0,5 mm
Edge angle: +/- 30 degrees inclusive, slightly convex

[kwakster]

Did this user Spyderco PM2 in S30V steel for a customer who had seen pictures online of another PM2 in S110V steel i did earlier, and which are also somewhere in this thread.
The man wanted the exact same full mirror edge he had seen on the other knife, it had to be 30 degrees inclusive, and it also had to have a guaranteed hair whittling sharpness.
Of course i told him that this S30V is not the best steel for a full mirror edge, but it was what he wanted, :)

The old edge had a few flat spots and a bit of a rounded point from use, but nothing serious.
Total time i spent on this knife was one hour, in a succession of Paper Wheels with 15, 6, 3, and 1 micron diamond compound.
As a comparison: the same full mirror edge on that PM2 in S110V steel the man saw online took me two hours.
Most of this time is going into the many visual checks i do in between with my Victorinox loupe under bright light, not into the actual sharpening.

These are the quick pics i also sent to the customer, and they can be clicked twice for a bit more detail.
The owner was satisfied btw.

[kwakster]

Hinderer XM-18 Slicer grind in S35VN steel.
According to my Tormek angle gauge the factory edge angle measured between 45 and 50 degrees inclusive, while the thickness of the steel just behind that edge went from 0.7 mm at the heel to 0.6 mm at the tip.
The knife is going to be used as a hunting folder, and the owner had 2 wishes: if possible no visually wide bevels, plus he wanted to be able to maintain the new edge on a Spyderco Sharpmaker.

Before sharpening:








Edge reprofiled to an almost exact 35 degrees inclusive with a Paper Wheel coated with 220 grit SiC, after which the burr was removed with a second Paper Wheel coated with 0.25 micron diamond compound.
The new edge is what i would call sticky sharp.

After sharpening:

[kwakster]

This special version of the Spyderco Paramilitary 2 in CPM-M4 steel & carbon fiber is in use with a Dutch knife forum member.
A small fraction of the tip had broken off and the apex sustained some damage (see pic 3).

This is how the knife looked before sharpening:








First i ground the old apex flat on the Tormek Blackstone until all damage in the apex was gone & there was a new point.
Then i made a new edge with 15 micron diamond compound on a Paper Wheel, which was then refined with 6, 3, and 1 micron diamond compound on dedicated Paper Wheels to a full mirror.
The new edge measures 30 degrees inclusive and is hairwhittling sharp.

After sharpening:

[kwakster]

Dustar Model 1 Arad 67 Commemorative combat knife from a collector.
The factory "edge" was very rough and also still had a burr so thick that i could lift the entire knife from the table by hooking it with my finger nail.
Edge angle was +/- 45 degrees inclusive which i left intact as the customer did not want wider bevels.
After grinding the apex flat on the Tormek Blackstone the edge was resharpened on a Paper Wheel with 15 micron diamond compound then deburred with a second Paper Wheel with 3 micron diamond compound, an the new edge can just treetop the hairs on the back of my hand.
Probably the most wear resistant D2 steel i have sharpened so far.

[kwakster]

This vintage Al Mar Applegate Fairbairn dagger from a display collection had factory edges which were rather coarse, had a few flat spots, and a flattened point.
Since the "R" from Rex Applegate's signature was already quite close to the ~ 50 degrees inclusive factory edge i chose not to reprofile but instead just polish the existing bevels a bit with successively 15.0 micron, 3.0 micron, and 1.0 micron diamond compound on dedicated Paper Wheels.
Both new edges can shave the hair on the back of my hand on skin level.

After sharpening:

[kwakster]

Another PM2 in S110V.
The new edge was done on a Paper Wheel with 15 micron diamond compound, and then refined with 6.0 micron, 3.0 micron, and 1.0 micron diamond compound, all on dedicated Paper Wheels.
The apex is keen enough to whittle several curls in a row on one of my chest hairs while holding the hair at the root end only.

After sharpening:

[kwakster]

The owner of this Maxamet PM2 had given his knife a forced patina treatment, and besides coming out a bit uneven the acid had also completely eaten away the factory apex as well as the very tip of the blade.
To say that the knife was completely blunt would have been an understatement.
The request was to give the knife a new toothy edge with a lot of bite while making it as sharp as possible.

Before sharpening:












Flattened the acid damaged "apex" some more on a 3000 grit diamond plate so i could start with fresh steel, then made a new edge on a Rubber Wheel coated with ~ 230 grit diamond powder & wax, then deburred on a Paper Wheel with 1.0 micron diamond paste & oil.
The new edge is ever so slightly convex, the new apex fits almost exactly in the 30 degree inclusive slot of my Tormek WM200 Angle Master, plus it can whittle one of my chest hairs at about 5.5 centimeters from the point of holding.
(i don't own a BESS tester)
The somewhat "fuzzy" shoulders of the new edge show how deep the acid has eaten away into the sides of the blade in some area's.

After sharpening:

[kwakster]

The owner of this Sebenza 25 bought the knife brand new through an official dealer in the Netherlands, but although he was and is still very pleased with the knife itself, he soon found that the factory edge didn't cut too well.
He tried to improve things with the help of a Spyderco Sharpmaker and a leather strop loaded with some green compound, but to no avail.
So he sent the knife to me, and the first thing i did was to measure the edge angle.
According to my Tormek Angle Gauge it measured 50 degrees inclusive on the straight part of the edge, going up to 55 degrees inclusive from the belly to the point.(!)
This is how the knife looked before sharpening:








First i removed the apex of the old edge by cutting a few times lightly into an old silicon carbide stone, after which i reprofiled it freehand on my Tormek SB-250 Blackstone to an even 30 degrees inclusive.
This was followed by a Paper Wheel with 220 grit SiC to smoothen the grindlines made by the Tormek, then refined with a second Paper Wheel coated with 15 micron diamond compound, and finally removed the burr with a third Paper Wheel coated with 0.25 diamond compound. (this leaves the 15 micron scratch pattern intact as much as possible to preserve bite)
The resulting edge treetops the hair on the back of my hand, can slice single-ply toilet paper, and survives a few cuts into my laminated testblock without any visible damage (checked under bright light with the loupe in my Victorinox SwissChamp)
This is how the knife looks after sharpening:

[kwakster]

Wootz/Vadim testing heat build-up in the edge when using Paper Wheels with diamond compound:



He never told me this in our e-mail conversations, but i recently found that he mentions me by name in the on-screen text,

[gooeytek]

Many years ago, I glued a zirconia belt on a used paper wheel and convexed this REX-121 K2, then diamond paste on another paper wheel to polish edge. Made it easy.

[kwakster]

Vintage Al Mar Denali mid-backlock folding knife with hollow ground blade from the 1980's and made in Japan. (probably by Moki)
The cocobolo handle is inlayed with a gold shield picturing a fighter plane and the text "United States Navy Fighter Weapons School".
The 1986 movie "Top Gun" with Tom Cruise and Kelly McGillis was partly filmed on the grounds of this elite school for US Navy pilots.
Bernard Levine thinks this version with the gold shield was a special edition, not standard production.

The original edge measured about 35 degrees inclusive and wasn't really sharp, so i changed the angle to 30 degrees inclusive with a treetopping sharp bling & bite finish.

Specs:

Length open: 17,3 cm
Length closed: 10,0 cm
Blade length: 7,5 cm
Blade thickness: 3,0 mm
Steel: Masahiro RS30 stainless steel
Hardness: 57-58 HRC (?)
Handle material: Cocobolo wood & satin stainless bolsters on brass liners
Handle thickness: 11,0 mm
Lock type: Mid-backlock
Weight: 100 grams