Sharpening basics, a question?

[galadduin]

I have been sending a users guide leaflet with the custom knives I make and I've been adding a section of how to sharpen my knives. I always state the edge angle on technical info section and on the sharpening section advise my customers to sharpen at half of that edge angle. Thus, if my chefs knife has 22 degrees edge I advise on the sharpening section to put the edge on stone or sand paper at 11-12 degrees.
However the info publicly available on the internet always suggest to sharpen at 20 to 22 degrees. What kind of kitchen cutlery has a 40-45 degrees of edge ? It really confuses me. What do you think of that???

 

[Nathan the Machinist]

What kind of kitchen cutlery has a 40-45 degrees of edge ????

Really crappy kitchen cutlery stamped out of prehardened low carbon stainless like 90% of people have in their kitchens. On the positive side, at least it won't chip when used against a glass cutting board. :thumbdn:

11-12 is a little extreme, but not over the top. That would work well on vegetables etc, but might be a little acute for something that makes a lot of contact with a cutting board or bone.

 

[galadduin]

Thank you for the reply Nathan, I will consider to tweaking my edge angles, may be 26-28 degrees instead of 22 for chefs knives...

 

[the possum]

I sharpen my old Sheffield carver at 5*-7* per side, and it's one of my favorite knives in the kitchen. Over time I may touch up the microbevel so that it gets to more like 8*-10* per side before I'm ready to reprofile, but I don't usually even use 20* per side on my axes. :barf:

 

[69_knives]

I always found that to be perplexing as well, especially when they give you a 20° - 25° angle guide to use.

 

[mete]

The problem is that some give the total angle and some give angle 'per side'. You might say '22 degrees total angle' or use a drawing.

 

[hellgap]

I would not suggest to any of my customers to sharpen the knife themselves first off most of them would grind it on a grinder not knowing anything about steel other than a sharp knife is a good knife. Most butchers and chefs are not skilled in sharpening properly as several chefs have told me and my good friend the butcher uses a steel to grind the steel edge back to a so so sharpness. I tell all the people ive sold to to return the knife to me and ill sharpen it for a very reasonable fee . I have now become very good at using my paper wheel system and now know what i was missing out on. I save myself countless hours sharpening knives. It takes me no more than 3 min to sharpen any knife where it was taking me 1 hour before. 20 degree angle is good and 17 for kitchen and filleting knives thats what i do . everyone is a little different. kellyw

 

[Salem Straub]

It's not that butchers are sharpening incorrectly. They are just getting a different edge than you. With the amount of use/abuse that butcher knives in a commercial setting get, butchers (and halibut fletchers, which I used to be) like to have a method of quickly touching up an edge on the line.

A steel is easy to clean, easy to use, and fast. It puts a different sort of edge on the blade than the process you might use for a woodcarving knife or straight razor. Instead of polishing the edge progressively finer until the finest/smoothest cutting edge possible has been obtained, it relies instead on the forming and constant realignment of a burr on the edge.

This burr gives an aggressive "micro saw toothed" cutting action, which glides through soft meat and vegetables like no-one's business. When the burr folds over or wears off, the steel is used to maintain and realign it as needed. This technique developed in tandem with chef knives of the western tradition, which tend to use softer steels than Asian knives and hence lend themselves better to this kind of sharpening.

A santoku at say, 62-65 Rc may chip and will certainly not sharpen as well with a steel. Just imagine, with a fairly soft chef knife, cutting meat all day, how much of a pain would it be to do all of your sharpening constantly on a Japanese waterstone? Or worse, an Arkansas oilstone?

Although I will say, most butchers I have met will probably not know these things... and will try to sharpen anything with a frickin' steel.

Sorry to hijack this thread a bit, I just like to talk sharpenin' too...

 

[hellgap]

I dont mind at all my oldest son was a legger at a meat plant and told me about all the ways they sharpen knives fast. The plant has 3 full time sharpeners working 24/7 my son agrees the steel is the fastest best way in the meat industry. He also told me through out the plant they have water grinders to get a better edge. My son told me cutting through the shit on the back legs of a cow when its -40 sucks the big one on knives and workers lol.

 

[galadduin]

I always tell my costumers not to steel the chefs knives I made, but they are afraid of sharpening as most of them are not aware of how fast and easy to sharpen if the knife is not dull too much. I feel it is our responsibility to educate them of hand sharpening methods. I welcome if any of my customer sends the blade back to me to sharpen it, but it is almost impossible to send each knife back to me every time it dulls. As I send most of my knives to different cities and towns shipment is too costly. So I try to be sure that the knives that have built to perform are sharp when they need to be used. So I encourage the users to maintain their own knives.

I've been testing the steeling method for my kitchen knives, it is quite aggressive on most commercial knives but it is not improving the overall cutting performance of the knives I made. It is not for example working on my hard and stubborn D2 chefs knives, when it is dull it is very hard to obtain the same sharpness with hand sharpening also. So most of the time I try to keep the geometry at the edge as thin as possible, so even it is not sharp enough it keeps cutting lot better than a factory knife. One of my customer has informed me that the D2 paring knife I made for her is cutting easily even after 6 months passed without any sharpening at all. It is used every day a lot.

Also I test some ceramic materials to field sharpen. I plan to build my ceramic sharpeners for each knife I sell. Even a piece of ball clay fired about 1150 C is quite good to sharpen a knife if you know how to sharpen. I managed to sharpen a dull RWL34 knife with the bottom of a mug (unglazed part) with ease, it is not hair splitting sharp for sure but this kind of sharpness is mostly enough for a working knife.

Most of the times we knife makers exaggerate the difficulty of sharpening, but we seek a hair popping sharpness which is not so important for most cutting performances. This kind of sharpness is needed by professionals like my oboe and bassoon reed maker customers but these professionals are mostly know how to sharpen a reed knife better than me. The normal user of a kitchen knife doesn't need that kind of sharpness, it is also not manageable sharpness as it will dull quite fast. We need to keep in mind these issues when making and presenting the user knives, and inform our customers how to maintain the knives. Also we need to keep geometry very thin as we have to accept that most of our knives won't be sharpened by some users for months or years....

 

[69_knives]

When I was a kid, I used to watch this Asian cooking show called 'Wok With Yan" and the host always sharpened his cleavers on the bottom of a plate on the unglazed ring.

I've been thinking that if I do sell any knives that I would like to include some sort of sharpening device but nothing too expensive or elaborate. Our local 'harbor freight' type store sells several types of inexpensive sharpeners, such as 2 sided and 4 sided diamond hones that are all over ebay. I was thinking maybe a 2 sided diamond hone along with a homemade leather strop, a chunk of buffing compound and some written instructions and either include it in the price of the knife or sell separately as an option.

 

[James_Terrio]

I was thinking maybe a 2 sided diamond hone along with a homemade leather strop, a chunk of buffing compound and some written instructions and either include it in the price of the knife or sell separately as an option.

I think that's an excellent idea for an optional "care kit". If you're making non-stainless knives, you could maybe include a small bottle of your favorite oil to prevent rust in storage. If it's a survival/bushcraft knife, include a ferro rod, maybe with a handle that matches the knife... the W&SS boys love those things.