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Posted on Fri Aug 26, 2022 on a few other forums.
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My nephews girlfriend is a hairdresser, and she asked me if i would try to sharpen her oldest pair of shears.
Years ago she had gotten it as a gift from her teacher, all this time had never been sharpened, and as a result it was so blunt that she didn't use it anymore.
Through Google i found that for 120 US dollars these shears seem to have a good price to quality ratio, so i thought that an attempt at sharpening might be worth it.

The edges were really quite bad, and as i had never done convex shears before i first had to think up a sharpening/polishing protocol that might work.
In the end i settled on 1000 grit SiC paper used with WD40 oil on glass, 15 micron diamond paste on the back of a narrow strip of SiC paper on glass, followed by 6 micron and 1 micron used the same way.
The hone line was repolished using only 1.0 micron diamond paste.

Just reassembled the shears again and the edges seem to work as they should, effortlessly cutting hair all the way to the point, but the real proof of the pudding is of course what the owner will think of it.
Will report back if i know more...

Restoring older knives is one of my hobbies, and i think this one came out rather well.
No Tormek involved, all regrinding/sharpening was done by hand on a bench stone and refining on wet & dry paper.
The knife is a made in Sweden Pontus Holmberg first model survival knife for the Swedish Air Force, made between 1948 and 1952.

This is how the knife looked when i bought it:





And this is how the knife looks now.
Blade has been hand reground/reshaped to it's original full convex shape, and in the handle the rotted leather midsection was replaced with new leather.
Sheath was also hand restitched and waxed.





















Full thread with pictures here:
https://www.bladeforums.com/threads/2-swedish-air-force-survival-knives.1776249/

Several years ago i made this small knife rest, a variant based on the original design by Tormek forum member Herman Trivilino.
Mine is being used for reprofiling/sharpening various blade shapes & sizes (flat ground is ideal, but saber ground is also possible), from the small blades in Victorinox knives up to expensive professional gyuto's with 210 mm blades.

A possible problem is that you would have to make such a knife rest yourself, as Tormek still doesn't offer something comparable.
I used a piece of Torlock cut from a Tormek SVD-110 tool rest (which remains functional afterwards btw), a few pieces of scrap aluminium & some metal screws.
A very important aspect is getting that piece of Torlock as square as possible, for which i used files and a micrometer.
With access to a precision milling machine it would be a piece of cake.

On top is a piece of 0.3 mm thin fiber-reinforced PTFE tape, which works very well for moving the blade across the platform and also to avoid scratches while doing that (up to a point)
For more blade protection i use plastic packing tape on the blade surface as well.

When used in conjunction with just enough water in the trough so that it doesn't splash the platform the tape lasts quite a while before i have to replace it with a new piece.
The lowest angle i can grind to is ~20 degrees inclusive.









Tormek SVD110 Tool Rest:

This thread was already posted on several knife forums about 10 years ago, and recently i got a message from a forum member from one of these forums that all pictures had become invisible, so i re-uploaded all of them, and this time also to a larger size.
Apparently people are still interested in older threads like this one, so i'm now posting the thread on this forum as well.

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Some time ago while surfing the net i found a website with Catra test results for 3 different ceramic knives: two by the well known Japanese Kyocera brand, and one from another (and unfamiliar to me) Japanese brand with the name Forever Company.
Next to various types of ceramic knives the company also seems to make a host of other specialty kitchen knives from various space-age materials: http://forever-k.com/en/ceramic/
Anyway, the 3 ceramic knives were tested on wear resistance, and the (much) cheaper Forever knife seemingly won by quite a margin regarding that aspect:

http://socialcompare.com/en/comparison/couteaux-en-ceramique-mpo3v9w

Now i know that wear resistance does not equal edge holding (especially with ceramic knives), but who knows ?
Maybe they're on to something.
Since i sharpen ceramic knives for others from time to time (and the two tested Kyocera models have always ranked the highest for me in the edge holding department so far), i became a bit curious about the Forever knife.
So i ordered the exact SC-16WB model that was tested from a Japan based E-Bay dealer for 45 US dollars including shipping to the Netherlands, and yesterday it arrived:











Specs:

Ceramic knife for right handed use (non-logo side is flat, while the logo side has a wide saber grind and a 70/30 edge
Overall length: 10.9 inch (27,6 cm)
Blade length: 6.3 inch (16,0 cm)
Blade material: High Density Zirconia
Blade thickness: 1,43 mm
Thickness behind the edge: 0,61 mm
Factory edge angle: 26/27 degrees inclusive
Edge finish: rather coarse with lots of bite (my estimate: somewhere around a 1000 grit)
Sharpness: Can shave my arm- and leg hair with the growth, not against it.
Not a single microchip can be felt using my nail, or seen through my Victorinox magnifying glass
Handle material: black plastic
Weight: 83 grams

I'm going to use the knife the coming months for standard kitchen duty, mostly to see how that rather coarse factory edge will hold up.
When the time comes i will experiment a bit with resharpening and write about my findings in this thread.

A recent thrift shop find, and bought for a fart and three marbles (dutch expression, meaning for next to nothing)
From research i learned that J&R Dodge Sheffield didn't manufacture anything themselves, but instead bought high quality cutlery, razors and tools from well established Sheffield makers and resold these under their Juste Judicato (Choose Right) brand, for instance in two stores they owned in Amsterdam.
That is most likely how this carving knife ended up in the Netherlands.
Back in the day in this country J&R Dodge were known for the quality of the double-shear steel carving knives they offered for sale.







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Specifications & measurements:

Overall length: 13.07 inch (33,2 cm)
Blade length: 8.07 inch (20,5 cm)
Blade thickness: 2,29 mm at the start of the swedge tapering to 0,44 mm at 1,0 cm before the point
Thickness behind the edge: 0.25 mm at the start of the swedge tapering to 0,16 mm at 1,0 cm before the point
Steel type: double shear steel
Handle material: black horn
Weight: 128,4 grams
The knife is handle heavy

Yesterday i received two of these Kohetsu HAP40 Santoku's from Chefknivestogo.com, a dependable US dealer for kitchen knives.
One of these will go to a Chef i know who has no experience ordering knives from abroad, and the other one will probably be sold to another Chef.





As often with Japanese knives the factory edges need some work to get them truly sharp, and these Kohetsu's were no exception.
One was just sharp enough to slice copypaper, the other reluctantly shaved a few hairs from my hand, and both of them had a few tiny burr remnants clinging to the apex.
Now both me and the new owner have zero experience with HAP40, so it will be a bit of a learning journey to finetune the edge into what works best & longest for him.












For it's first sharpening i chose to just leave the factory edge angle of between 17.5 & 20 degrees inclusive (!) intact and just resharpen the existing narrow V-bevel with 3 micron diamond compound on a Paper Wheel (with such a small edge angle this actually provides for an ever so tiny, but just visible burr), and deburr with 1 micron diamond compound on a second Paper Wheel.
With the naked eye it looks like nothing was done to the knife, but the new edge can whittle a chest hair towards the hair point and slice a paper towel clean.
Now we have to find out if the new owner can work with it, and what's especially important; for how long exactly before it needs resharpening.
My guess is that eventually he will settle upon a bit coarser edge, but we will see.



Specs:

Overall length: 29,5 cm
Blade length: 18,0 cm
Useful edge length: 17,4 cm
Blade thickness: max 2.06 mm
Steel: Laminated HAP40
Hardness: 65 HRC
Blade: double sided convex grind with half-sided convex bevel and a narrow V-bevel on top which forms the actual edge.
Edge angle: between 17,5 and 20 degrees inclusive (measured with Tormek WM200 Angle Master)
Handle material: Pakkawood
Weight: 170 grams

This type of strop is what i sometimes make & give to people who regularly bring me a CRK or other quality (Chef-) knife for sharpening and/or some TLC, so they can maintain & keep the appearance of their new edge themselves for some time.
Even a few professional Chefs in my area with expensive gyuto's and santoku's in modern PM steel types are using these same strops with good results, so they keep telling me anyway.
I use them myself as well, and they are easy to make.




What you see is a new & cut-to-size piece of clean MDF (medium density fiberboard) coated with a thin layer of 1.0 micron (~ 14000 grit) mono-diamond compound, and i put 4 self-adhesive rubber bumpers on the bottom.
These make the strop non-slip plus they elevate the working surface a bit more which makes the strop more convenient to use on a table (more room for your hands)
Due to the harder surface the chances of rounding your crisp apex are also greatly diminished when compared to stropping on compressible materials like leather.
The strop surface can also be cleaned from time to time with a microfiber cloth and some acetone, which will remove all or most of the swarf without removing the diamond particles, as these become (partially) embedded in the MDF surface during the stropping proces.




But this is (literally) the key element: the placement on rubber bumpers also provides the strop user with acoustic feedback by isolating the MDF from the table (a bit like the bars on a xylophone); you can actually hear when you're arriving at the very apex during stropping movements as the audible sound changes, which makes the stropping proces very easy, even for absolute beginners.



The CRK Nyala used as a prop for the pictures was reprofiled (from 35-40 degrees inclusive to an even 30 degrees inclusive) & sharpened (with 15 micron diamond compound on a Paper Wheel).
The owner only uses this quite expensive knife to cut oranges, about 5 each day, i kid you not.

A small black ceramic backlock folder without any markings (Böker ?) i did in 2013.
This well made knife had practically no edge and no point to speak of when i received it, and even opening mail with it was difficult.
I used the Tormek SB-250 Blackstone graded with diamond to around 1000 grit for freehand reprofiling, followed by 3 Paper Wheels coated with 15, 6.0 and 3.0 micron diamond compounds for refining & polishing.
The new edge fits in the 30 degrees inclusive slot on my Tormek angle gauge, is slightly convex, and can shave the hair on my leg in both directions.









Specs:

Length open: 4.72 inches (12,0 cm)
Length closed: 2.76 inches (7,5 cm)
Blade material: black zirconium oxide
Blade length: 1.57 inches (4,5 cm)
Blade thickness: 2,0 mm
Handle material: Ivory Micarta & Nickel Silver bolsters
Weight: 61 grams

This traditional Argentinian Ju-Ca brand fixed blade belongs to a friend of a friend, and as you can see the point was broken off and the handle was also in need of a bit of TLC.

Website of the Argentinian father & son team, who have been making these knives since 1959: http://ju-ca.com.ar/

For quite a few years this Buck Strider 881 mini tanto in BG42 steel was gathering dust in a drawer, as to me it was more a knife-like object, literally unable to cut anything.
Over the last few weeks i changed that with the help of my Tormek SB-250 stone (for the point area), a 300 grit diamond file, a Foss 7205 black/green silicon carbide stone, and some 400 grit wet & dry SiC paper on glass (for the straight edge)
The apex on the now full convex blade measures somewhere between 22.5 and 25 degrees inclusive, and i'm first going to do some test cutting to find out if i can safely lower it a bit more.
Also rounded the overly sharp G10 grip plates a bit and sanded the screw heads.

Before:








While grinding the blade with the diamond file:







After the 400 grit SiC paper and removing the tiny burr on a piece of hard cardboard with a dab of 1.0 micron diamond paste:






Considering all work was done with only one eye currently functioning at about 80 % (plus a pair of reading glasses) i'm quite pleased with the result, :-)

Sometimes i remodel worn out or discarded meat carving knives into very narrow shank-like knives, which i then give away to certain Chefs & butchers.
This old Swibo i did a few years back, and it has quickly become the favorite bird & trout knife of a local Chef.

The rigid blade is hand convex ground up to 400 grit wet & dry SiC, it has an edge angle somewhere between 25 and 30 degrees inclusive, and the back of the blade is also convexed to a degree (which thins the blade a bit more & allows for better twisting & turning)
My Tormek T7 fitted with an SB-250 Blackstone was used in a supportive role; to grind down the back of the blade a bit before i continued with hand convex grinding.
The hard rubber-like handle has no real guard, only a few shallow finger grooves, which provide for quite a lot of grip.
Very useful knife according to it's owner.

On this knife the Tormek was not used for the actual sharpening of the edge, but in a very important supporting role.

Right hand Takamura R2 Gyuto 210 mm from a local Chef, who got it as a birthday present from his wife.
The knife has already been used for two months in the commercial kitchen and it was time for it's first resharpening, which i did yesterday on a Paper Wheel with 15 micron diamond compound and then deburred on a second Paper Wheel with 0.25 micron diamond compound.
The idea was to make an edge that would do both slicing & pushcutting well, and also to remove as little steel as possible from the fine and thin R2/SG2 blade @ 63-64 HRC.
The new edge measures +/- 20 degrees inclusive and can whittle a chest hair from root-to-tip at about 4 centimeters from the point of holding, and after a few test cuts into a old piece of beechwood cutting board.

I took these pics with an old Ipad and actually wanted to erase them again as being not good enough until i enlarged the last picture twice.
At first i thought i saw small dirt spots on the new bevel, but those tiny white specks were actually the sliced off peaks of the micro-dot structure on the inside of the flimsy plastic blade protector sleeve.
















Total procedure:

- Repairing the point of the knife (about 2 mm was broken off) was done on the Tormek SB-250 stone by grinding the back of the blade until there was a new point.
- Flattening the old edge was also done on the Tormek (by grinding off about 1/10th of a mm on the side of the stone.
- Sharpening to burr was done exclusively on the 15 micron Paper Wheel.
- Deburring was done exclusively on the 0.25 micron Paper Wheel.
- Rounding the heel of the knife was again done on the Tormek (by grinding off a tiny bit of steel on the side of the stone.)

Currently doing a bit of tinkering, as in making my own version of Herman Trivilino's knife rest (using a cut-off piece of Torlock and 2 scrap pieces of aluminium), plus testing an MDF wheel with 1.0 micron diamond paste.
I'm already a bit further with the knife rest (ground in the hollow part on the SB-250 stone and put plastic tape on top to avoid scratching knife blades), and the first cheap knives i did came out quite well.
Probably going to replace the aluminium pieces with one piece of more rigid steel, but for now it seems to do the job.



The MDF Wheel is a testbed to find out what it can do exactly and how well.
I have been using MDF benchstrops with diamond compounds succesfully for quite some time now, and it was time to see if a motorized version would also work.
So far i found that it indeed works very well for removing burrs on harder & more wear resistant steel types (think S30V, ZDP-189, etc), as well as touching up existing edges on the same steels.
On softer steel types the leather wheel works noticeably better.
Also experimenting with various slots in the surface, both to trap steel debris as well as to find out if the direction of the slots has any influence in burr removal.
Will make a few more of these wheels in the future.