asdfg

I've never liked steeling but having a sharpener that can be sterilized probably has its advantages in the food and health care industry. I know we used them in dentistry. I would imagine that a steel used repeatedly without at least disinfecting it would a virtual repository of bacteria and germs.

Anyone know how well a ceramic would hold up to a steam or chemical sterilizer? I would suspect that they'd crack from the heat. Wiping them down may work though with bleach or some other such thing. My butcher boils his steel on occasion to sterilize it. I've seen it sitting there on his hot pot.

STR
 
I have tried ceramic rods many times, yes it does sharpen, but my knife is never as sharp as when it is steeled only. Mybe I am doing something wrong, but the knife will just glide through the meat with little pressure when steeled, but seems to drag and not have the same level of Keeness when used on ceramic.
Alot of guys use Dexter-Russell ceramic rods in the meat works, my knives are much sharper then any of these guys. Do we need to try a different brand of ceramic or is it that for meat cutting we need a highly polished edge and cardboard cutters use a 'toothier' edge? It seems that by using a ceramic rod that is about 1000grit you are taking a step back from when originly stoned on a black Arkansas stone than onto a chromium oxide strop.

All the ceramic rods at work get dipped in hot water sterilizer (82.5deg C) havent seen one crack yet.
 
Meatcutter.

Am I understanding you correctly?
You use a steel, ( Quote..The steel I use is a Wm Gregory of Sheffield and is at least 120 years old) after you have refined your edge with the black Arkansas stone and a chromium oxide strop.

Unless your steel is absolutely smooth, are you not going back a step?
 
The edge that you get from steeling a knife is particularly good for slicing meat. It has a micro texture that is sort of rough so that it slices well. It is not the same type of roughness that you get from using a coarse hone, it reminds me of broken glass or torn sheet metal. I think of it as sort of an organized burr. It wouldn't hold up well to chopping on bone, but it cuts through meat, fat, and sinew really great. You can get a similar effect if you sharpen with a mill bastard file if you know what your're doing. Even as the edge breaks down it works on meat.
 
I believe the steel is just realigning or straightening the already polished edge, no black or filings can be detected on steel or knife after steeling as can be found on abrasive type sharpeners.
I don't know if you are fimiliar with the type of steel I use, but here in Australia more often you will find the best boners/slicers, slaughterman using custom steels made from old forged steels or files, that have been rubbed back smooth and used as is, or then pitted with an acid treatment. You have to steel very lightly, which can take some practice, or they can roll the edge over.
Maybe I am wrong, possibly micoscopically metal is being removed, but it isn't evident as with ceramic rods. I have used F.Dick polished steels with good results but now the quality seems to have dropped off, after about 8 months of heavy use they are useless and will dull the knife more than sharpen it.
 
Jeff,

I am starting out with a highly polished edge, chromium charged strop, which gives a very sharp edge with no detectable burr. The knife cuts as well before steeling as it does 5 hours into the shift (assuming I haven't dropped the knife or hit my mesh glove Duh!:mad: ), so I am not sure about the organized burr being created. I can gut, skin and debone many carcasses of kangaroo, or stick and butcher wild boar with my steeled knives. They only dull quickly if there is allot of mud or dirt in the hide, but surely this will dull most knives prematurely. The edges hold up well whilst de-boning, there is allot of bone contact when moving through the joints, it is just a mater of leaving more relief in the blade if I know it will be used near bone. But as for "chopping bone" no knife in my kit will ever be subjected to this kind of torture.

I am sure you can sharpen a knife on a mill file but if you tried this in a boning room you would be in for a very, tiring long day indeed.
 
STR said:
I've never liked steeling but having a sharpener that can be sterilized probably has its advantages in the food and health care industry. I know we used them in dentistry. I would imagine that a steel used repeatedly without at least disinfecting it would a virtual repository of bacteria and germs.

Anyone know how well a ceramic would hold up to a steam or chemical sterilizer? I would suspect that they'd crack from the heat. Wiping them down may work though with bleach or some other such thing. My butcher boils his steel on occasion to sterilize it. I've seen it sitting there on his hot pot.

STR
Click to expand...
The best way to sterilze ceramic is in a 200 PPM KMN04 dip.
 
Meatcutter said:
The knife cuts as well before steeling as it does 5 hours into the shift ...
Click to expand...

So you only steel once or so per day, or you maintain that high sharpness all day long with frequent steeling? How dull does the knife get before you steel it?

I am sure you can sharpen a knife on a mill file but if you tried this in a boning room you would be in for a very, tiring long day indeed.
Click to expand...

It leaves a very aggressive edge which works well as a saw, considering that a slice effectively constraints the cut depth significantly I would expect most meat cutters, unless the blades are really long, to prefer highly polished and very smooth edges.

Meatcutter said:
Do we need to try a different brand of ceramic or is it that for meat cutting we need a highly polished edge and cardboard cutters use a 'toothier' edge?
Click to expand...

Cardboard can work well with either coarse or fine edges depending on if you are slicing or push cutting. You can get very fine ceramic rods (Syderco has ultrafine ones), the diamond rods in contrast are *really* coarse, the edge has teeth so large you can see them even under 10x magnification, you can really feel a large difference pushing them through anything, that is an edge just made for draw cuts. DMT makes very fine diamond abrasives (finer even that the chromium/aluminum oxide buffing compound) but the rods are much rougher.

Nosmo said:
Unless your steel is absolutely smooth, are you not going back a step?
Click to expand...

Even the lightly grooved steels will refine an edge if you use them *lightly*, they only become files under high pressure.

Meatcutter said:
Maybe I am wrong, possibly micoscopically metal is being removed, but it isn't evident as with ceramic rods.
Click to expand...

It is on a much finer scale, it is essentially metal on metal wear, whereas ceramics/diamonds will just cut right into the steel. You bring up a point I missed which is that smooth steels can maintain the structure (grit level) of the origional edge whereas a ceramic/diamond rod will reset it to their grit level, thus a smooth steel is more flexible in that it can maintain both a coarse or very fine edge, the ceramic/diamond rods can only do one or the other depending on their grit.

-Cliff
 
A smooth steel will not cut out metal like a file or an abrasive hone would do. What it will do is bend metal back into alignment with the edge. The problem is cold-working of the edge material. Cutlery steel is hard. Even when it is very thin (like the material at the blade edge) it cannot be bent back and forth very often. Each time that it is bent the concentration of defects in the lattice structure of the steel gets higher and higher. This makes the material get stiffer and more brittle with each bend. The material gets harder and more brittle which is saying that it gets more like glass to work on. Like glass the edge will start to chip with repeated steeling. If the dings that you are straightening with the steel are small the chips will be very small. The chips are also likely to be very sharp like broken glass. The effect is very microscopic.

When you use a knife normally you won't notice the other problem, that the edge has gotten harder and more brittle. If you were using it for whittling or chopping on hardwood you would see significant chipping. When I test the durability of a hunting knife blade I use it to chop notches in the edge of beef rib bones. A cleanly sharpened BG-42 alloy blade will chop through bone like that without noticeable effect. If I used one of my thin kitchen knives it would be damaged. If I did it with a knife that had been steeled repeatedly it would chip.

I use a ceramic steel in the kitchen because most of my cutting is not on meat. Most of the time my knives are used for slicing and dicing on a cutting board. The board is getting cut more than the food. When my son gets a hold on a knife it may be used to cut food inside of a cast iron fry pan. The dulling is different than what you see in a meat plant. When I am working with meat I may pull out my smooth steel (an antique F Dick), but this is most likely with one of my old German or French carving knives. My Sabatier really responds well to steeling, my Japanese stainless blades are too hard.
 
I think with meat workers, the deformations are so small, and the steeling so frequent and light that the edge can be cold worked for a long time. It might be interesting to see an edge retention comparison for example with steeling done very frequently vs delayed, on cardboard for example steel after say every few meters, vs every 10 meters and see which edge is sharper after say 50 meters.

If you look at Verhoeven's work, he showed that steeling induces edge damage realy quickly, anything beyond 1-2 passes per side wasn't productive so it seems unlikely that repeated steeling would be different, worse probably because it is deformed again from use. However the influence of edge angle and force applied has to be considered.

-Cliff
 
This is one hell of a thread. Thanks Meatcutter, as it's nice to have a real user inputting information. As well, welcome to the forum.

Of course, I'm still totally confused and think that I'll stick with my perfectly smooth steel and use my ceramic steel only when the blade needs a little "zing".
 
G'day again, Just finished another shift on the knife. I have only started experimenting with the chromium oxide charged strop after honing and I am getting excellent results. My knife cut wonderfully all day (did about 5500KG of chilled beef) and will get a few hours out of it on Monday. It is showing that the higher polished the edge the better results are obtained.

When I steel a knife I use very slow deliberate strokes of around 2 to 3 strokes per side, with as LITTLE pressure as possible. I never let the knife get dull before steeling again, but try to maintain the high level of sharpness. I think this is a very important point with steeling a knife, it is better to keep it as sharp as possible without letting it get dull, rather then letting it get dull and then try to bring the sharpness back. I think this is the point Jeff is getting at with the over working the edge, by keeping the edge straight you are moving the metal a minimum, but letting it dull a lot more will mean the metal is getting moved back further and working it more.

I always have a laugh to myself when new guys start on the knife, they think you have to steel very fast like you see old butchers or chefs. But after a few days of pushing a below average sharpness knife, they soon learn to slow down and take more care with their steeling.

Cliff, where can I find information on Verhoeven, does he have a book?
 
Thanks for the link to Verhoeven's work, it is like A grade porn to a sharpening nut. Haven't had time to have a good read of it yet but I did notice he used a Razor Edge steel for some of his tests. I have a straight steel made by Razor Edge and I wasn't reel impressed buy it's performance. At first it was way to coarse and would ruin an edge after a short time, I did give the steel a rub with some emery paper but still found it laking somewhat. The guide that was on the end of the steel, though good in theory, was way to steep of a angle for my liking. Might pull it out again one day and have more of a play with it. As for the other steel he used I have tried similar one and they were useless, so I don't know that I can make any concusions on he's findings on steeling, still it's good stuff thou.

I sharpen my knives on a Lansky guide that I have customised a bit. I removed the rear finger screw and drilled and tapped a 3/16 thread in its place then fitted it with a machine screw with a hex key head so I can get it nice and tight. I also replaced the alloy rods with 1/8 stainless rods as I found the alloy one supplied tended to bend easily. The reason I chose the Lansky over other systems is it is nice and compact for taking to work each day, and I can use it without the need for a table or workbench to work at. I keep my work knives very thin, the edge relief is set to the minimum for the task it has to perform, obviously a knife used for boning will have a thicker relief than one used for slicing.

I use a double bevel edge, the secondary bevel is cut with a diamond hone with the rod pushed all the way into the slot and in the 25deg mark on the guide. The primary edge face is cut firstly with the ceramic hone with the rod level with the bottom of the hone as per instructions and in the 25deg hole. Then I follow with a black Arkansas hone set the same as the ceramic.

I would love to experiment with different some different types of steel blades, problem is getting them made with food safe handles.
Anyone know what steels are use in makes of butcher knives like, Victorinox or F.Dick etc.
 
The European knives are made from European alloys which makes it less edifying to know the types. I have looked at equivalence tables and they don't seem accurate to me. Maybe it is best to talk about how the alloys seem to perform relative to more familiar alloys.

For me the Victorinox steel is pretty durable, but it doesn't take as good an edge as German knives typically do. For that reason I would rate it as similar to 440A and in the same class as old American made Chicago cutlery knives. It does not seem to be cryo treated like Cutco. Many of the German knives take a better edge than Victorinox and seem to have a similar edge holding ability. I would put them in the AUS-6 class.

There is a wider variety of Japanese stainless cutlery alloys, but they are generally all harder than German types. The basic "molybdenum stainless" that some of the cheaper knives use seems to be similar to the old 425M that Buck stopped using because customer found it too hard to sharpen. There are others that are labeled vanadium or vanadium-molybdenum alloy that are similar to AUS-8. MAC Original Series and AG Russell's house brand of knives fall into this category. They are pretty hard for kitchen knives, around 58 RC, so they are harder to sharpen than German blades, but they take an extremely sharp edge. Next up are the Spyderco/Masahiro knives that use an MBS-26 alloy hardened around 60 RC. This is about the same to sharpen as AUS-8, but is very stainless and holds an edge under a lot of pressure. The next step up are stainless alloys that contain vanadium and tungsten like the MAC Superior Series. These take extremely sharp edges, resist abrasion and are in the 60 RC range. These are pretty similar to VG-10 or AUS-10. There are also extremely hard carbon steels which are in a class by themselves.

The French Sabatier knives that I have used are a mixed bag. I like the Au Carbone carbon steel (it is similar to 1084). The stainless seems to be similar to 440A.
 
Meatcutter said:
...I don't know that I can make any concusions on he's findings on steeling ...
Click to expand...

Interesting, J.J. of Razor's Edge developed his steels for meat cutters and similar, he has three basic types, the long straight one, the folding one and the desktop model. I have used the latter two and they were *very* smooth. I don't in general do a lot of extensive steeling for reasons noted in the above, but they are in general well recieved in the industry. You might want to drop them an email, they are internet active I have corrosponed with them in the past.

I use a double bevel edge, the secondary bevel is cut with a diamond hone with the rod pushed all the way into the slot and in the 25deg mark on the guide. The primary edge face is cut firstly with the ceramic hone with the rod level with the bottom of the hone as per instructions and in the 25deg hole. Then I follow with a black Arkansas hone set the same as the ceramic.
Click to expand...

So this results in a micro-bevel at 25 degrees per side? What is the relief angle?

I would love to experiment with different some different types of steel blades, problem is getting them made with food safe handles.
Click to expand...

Inert like plastic?

-Cliff
 
Generally the "Sani Safe" knives have handles that are molded on. You need to not have places where bacteria can hide inside the handle. You also need to be able to run the knives through a three-step wash, hot detergent, hot water rinse, and cold bleach solution soak. Plastic or metal molded handles are generally the way to go.
 
Cliff

My measurements of the Lansky guide suggests the 25 deg mark is closer to 21.8 degrees. When you say: what is my relief angle?, do you mean my secondary edge bevel, that would be a few degrees less about 19 deg I guess. Otherwise I just rub the blade flat on a Razor Edge coarse stone until I think it is about right, just using my fingers and eyes to gauge the right thickness. I would like to know how to measure this accurately as sometimes I can get some inconsistencies especially when changing brands of knives with different hardnesses.

I dragged out the Razor Edge steel today and had a bit More of a play with it, still not up to scratch. It is disappointing as I know the work J.J. has done in the meat industry. Might drop them a line.

I think there would be a problem with knives in the meat works with super hard knife steels around 65HRC, as I know some custom made sharpening steels are hardened to around 63HRC. So I think the knife would bite into the steel, maybe this is where the ceramic rods come into their own.

Would like to here of some of your sharpening tips if you can see a problem with the way I do things as although my knives are quite sharp maybe they aren't as sharp as they can be.

meatcutter.
 
You must log in or register to reply here.
Back
Top