sharpening knives

[dgleeson]

Hoping for some insights here on knife sharpening.
I understand there's a preference in shoemaking for a knife bevelled on one side and flat on the other (chisel grind) as it's effectively sharper for a given bevel angle. Is it possible to convert a knife bevelled on both sides to a single bevel without significant reworking?
I have one knife that is clearly flat on one side and bevelled on the other, the others all have symmetric bevels but I would like to convert at least one of these to single bevel.

Different question... when stropping does the leather strop need to be smooth? When I started sharpening, following instruction but not really understanding the why, I stropped my knife on the leather when it still had a burr on one side from the sharpening. I did this many times and the end result is that my strop is "fuzzy" in places. To my mind his strikes me as problematic, if following the "scary sharp" method I sharpen my knife on ever finer micron grits... surely I end up in undoing some of this by stropping it on bumpy uneven leather?

Final question from me today... is the preference for a single bevel knife just for skiving or does it apply to clicking too?

[dw]

I'm sure there are a dozen different takes on this subject but IMO, if you understand what you're doing and your wrist and hand are firm enough it doesn't matter if the blade is sharpened from one side or both. It seems to me that if a blade is beveled only from one side and the flat side is laid against the surface of the leather and the leather is on a flat surface, the blade will have a little less 'bite' than if the blade were beveled from both sides. But again that is, IMO, entirely dependent on how well one controls the blade.

As far as the bevel angle, the maker controls that--regardless if the blade is sharpened one side or both. That said, the rule of thumb is that a flatter, longer bevel will generally be sharper than a steeper angled blade but the sharpness of a steeper edge will last longer than the flatter edge. Only stands to reason, IMO.

It is possible to convert a double bevel to a single bevel but it takes time and it takes a fair amount of metal along with it.

I use double and single beveled blades with equal facility both for skiving and for clicking.

FWIW, YMMV

[dw]

BTW, traditionally the best strops were made from shell... which technically is not even leather if leather is defined as a preserved skin or hide. Shell is a muscle sheath that lies under the hide. It has a unique and dense surface.

I suspect that if you made your strop from shell you wouldn't have the problems you're experiencing.

That said, my strops are all just veg tanned cow... usually shoulder or belly. But I charge the grain surface with a buffing compound such as tripoli. Such compounds are formulated to be more or less abrasive--some for buffing soft metals and some for hard metals. I even have a few hard strops that I have infused with linseed oil and carborundum (?) grit.

Stropping with compounds such as tripoli will remove the wire burr on the edge of your knife without dulling the edge--actually refining it a bit and making the edge sharper.

Sometimes you can even give new 'life' to an edge that has lost its edge, so to speak.

[das]

IMG_0658.JPG

FWIW, my strops or "stopping sticks" (narrow wood paddles) are faced with flesh veg cowhide, charged with red jeweler's rouge on one side, 600 grit wet-dry paper on the other. I rarely need to touch the 600 grit but maybe every week+, but I strop on the rouge side several times a day in heavy use. On a brand new knife I use a fine (orange) India stone to set up the initial bevel where I want it, and maybe twice a year thereafter.

[nickb1]

I used the leather from a couple of old razor strops, with Skerper brand stropping compound, green on one side and black (finer grit) on the other, glued to a thin wooden board like a paddle. It appears to be veg tan cow leather. I have another board with 600, 800, 1200 and 1600 grit wet and dry papers. I find that the once the blades are sharp from the papers and honed, generally I just need to keep stropping them with occasional touch up on the finer papers. I put one flesh side out and the other grain side out, they both work but I think the flesh out is better as it can flake off the grain side.
The British tradition seems to be the same as @das's method, but it seems many West End makers also use the stropping compound instead of jewellers' rouge. If you just heat the stick of stropping wax and rub it in it lasts for ages.

[carsten]

In forums dealing with classic shaving methods, often a green chrome III oxid paste on a leather strop is used instead of jewler's rouge for keeping razor blades sharp. Works well for my shoemaker knifes.

[dw]

@carsten

Got a source? link to a source?

[carsten]

@dw I got mine here: https://herbertz-messerclub.de/Streichr ... CWEALw_wcB
Its rather small (maybe 2,5cm , and 1 cm diameter) , but I think there are also larger ones available. In German it is called "Schleifpaste" or "Schärfpaste", maybe this one will do as well: https://drechslershop.de/schaerfpaste-g ... rsEALw_wcB

[dw]

Thanks.