Testing a Few Questions

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me2

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Oct 11, 2003
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I read a few posts here that made me wonder if it really held true or not, so I decided to try a few tests to see what happens. First is that sharpening with a belt sander will ruin the heat treatment on the last bit of edge, leading to rapid degredation and low edge holding. The other is the persistent rumor that cardboard dull knives very quickly.

I took my favorite Food Network faux damascus 4.5" blade Deba knife and gave it a freshsharpening with a 220/1000 grit waterstone, followed by a 20 degree final honing with the 204 Sharpmaker (204 for short). I did the edge flex test on a 1/4" shank round screwdriver and it passed at various location on the edge; visible deflection under light with full return after force removed.

Next I tried an unorthodox test. I cut some bread ties on a plastic cutting board. I made 2 or 3 cuts and checked for chipping. There was nothing visible, but I could feel something when I ran the edge along my fingernail.

Now for the fun part. I resharpened on the 204 using the recommended 20 strokes per side through all 4 grits and was rewarded with a hair whittling edge. Then I began cutting cardboard. I reduced 2 pizza boxes, and various other boxes around the house into 2 x 3 inch pieces, roughly. The knife quit shaving hair, but would still easily cut printer paper. I steeled the edge on the flat side of my trusty Faberware 8" blade chef's knife and it was back to shaving sharp, and would even catch a few hairs above the skin. After about 5 boxes of cardboard, the steeling still restores a hair shaving edge, and it has not lost the ability to cut paper yet. What do I have to do to dull this thing?

The interesting part will come after I dull it to the point that steeling doesnt work anymore. Then I'll resharpen using the belt sander and a worn 180 grit belt followed by leather with buffing compound. This also gives a hair whittling edge, but we'll see how it holds up to the same treatment.
 
My most valuable bit of info may be the effectiveness of steeling. I've never used it regularly, but it sure works on this knife.
 
Still going. I've cut cardboard and steeled the edge back several times. Its still hair shaving sharp. At this rate, it may be months before it dulls enough to require sharpening, if for no other reason than I need to get more cardboard.
 
How long does the edge last between steelings? I've given steelings up because when I would do it, the edge would be very sharp but not as long, then after the next steeling less so, and so on. I used to steel 3 or 4 times between sharpening, but don't use it much any more.

I'd be interested to see what your results are. Maybe I've been steeling incorrectly...
 
Its pretty effective so far. I've been steeling using the flat side of my Faberware chef's knife, not the grooved things that come with kitchen sets. Those I detest, though I've used them in a pinch. The first time I started cutting then steeled the edge, it lasted quite a while. It's difficult to make time estimates since I've been doing this over a period of 2 weeks or so now.
 
this is great for resetting an edge when cutting meat or other messy jobs. however if blade is pretty clean & dry then stropping is easier & more effiecent. if a person is doing lots of meat & fish i suggest the F. Dick Multisteel. these are the rolls royce of steels.
 
Finished some more cardboard cutting, and the steel still brings the edge back to shaving sharp, though it now feels sharper on one side than the other, so I've got a little wire edge going. It still cuts cardboard easily. This is a huge amount of cardboard to cut and still not go to the stones. I may be buying one of those chef's knives to cook with so I can keep the current one for steeling. FWIW, this knife tested just behind my M2 knife at cutting cardboard until it wouldn't split a plastic grocery bag. Knives that won't split the bag will still shave hair from my arm easily. At this point I've lost count of the cardboard and will just keep cutting until I run out or the steel won't sharpen it anymore. I'll have to start my sander vs. hand honing experiment over again. I'll try to get some rope to cut for that, since cardboard apparently doesn't do much.
 
me2 i've seen butchers working in small shops cutting up pigs & cattle, they would hit that steel ever so often to true up the mini teeth of the edge. it seemed like those simple carbon butcher knives kept cutting forever. a good steel aligns the edge as it polished the bevels.i believe that proper steeling will keep a blade going for a long long time.check out an f. dick multisteel if you get a chance.
 
I've always thought the flat steels pictured in my Gun Digest Book of Knifemaking were a good idea. The serrated steels that come with blocks now are craptastic. A smooth steel, especially one that is flat and doesn't put too much localized pressure seems a good way to go. I'm thinking of polishing up a section of another M2 saw blade I have and using it as a flat steel.
 
me2 said:
I've always thought the flat steels pictured in my Gun Digest Book of Knifemaking were a good idea. The serrated steels that come with blocks now are craptastic. A smooth steel, especially one that is flat and doesn't put too much localized pressure seems a good way to go. I'm thinking of polishing up a section of another M2 saw blade I have and using it as a flat steel.
Click to expand...
You're a masochist! :D But we appreciate it and your insights, thanks! I'm going to have a go at some more cardboard as well, my all time champ was a Queen 4180 great thinned down. I've gotten some more since then that might give it a run for it's money.
 
While the steeled edge is hardly optimal sharpness, it is sharp enough for nearly all knife uses, and will apparently last a while. I'm amazed that I missed this for so long.
 
Thats it, I'm done. I must have cut enough cardboard into 2" squares to make up a refrigerator box. It still just needs a steeling and it's back to shaving sharp. I've started steeling my Delica as well. Soon I'll try my Griptillian and then my Cara Cara. Also, I now say phooey on cardboard being abrasive. If I can steel the edge back after this long, it's not abrasive enough to wear down good old hardened steel. I'm going to belt sharpen this knife this weekend, but I'll only be able to repeat the wire cutting and edge flex tests. I didnt keep good enough notes to be able to repeat the cardboard cutting.
 
How many times in total did you steel? Did you get rid of that wire edge ok, or did the cardboard do that for you? Go soak your wrist and elbow in hot water and epsom salt!!!! :D

Thanks!
 
I steeled it 6 or 7 times, possibly more. There was definiately a wire edge there. It would shave hair better on one side than the other. Careful steeling left it barely noticable, or maybe folded it up against the edge so it was out of the way.

Conventional methods of getting a burr off don't work for me. I've tried stropping on cardboard, drawing through a board (2x4), stropping on leather, and a couple of others. The only thing that works is using the stones, and sometimes I have to cut directly into them to remove the burr. This only applied to hand sharpened edges. My 1x30 leather belt on the HF sander works after raising a wire with just about any grit above 120. It will even work at 120 if I'm carful/lucky.

I started on the Cara Cara last night, cutting soda cans. 144 cuts about 3.5 inches long each and I haven't needed to steel it yet. It still shaves hair off my arm. The Food Network knife above would get dull enough that it wouldn't even scrape shave, but a few passes on the flat of the chef's knife would bring it right back. Its back in the kitchen rotation now, until this weekend.
 
Almost all I ever use for small edc knives is an antique steel and a ceramic rod. If I get into some heavier use on my work knives (today I used my MUDD to pry carpet pad staples out of plywood), then I'll have to go back to the belt grinder. But generally, steeling and the ceramic is all that is necessary.

Andy
 
If the question is about burning the temper out of the steel with a belt sander for sharpening, the answer is you can do it almost instantly on a belt sander.

If you take your time, and dunk the blade in water to keep it cool, every pass it will be fine.

The real high risk place on sharpening is the tip. There no where for the heat to disperse on the tip to keep it cool. Use a lot of caution on the tip, and keep the blade cool and no problem (except for rounding, which is another issue, if you are slack belt sharpening and going convex).

As to steeling, it does work great for bringing an edge back quickly. I don't have a quality steel, but have actually used a smooth screwdriver in a pinch.

Mostly I just strop, and use the belt sander for damage on my beaters when it needs some material removed.

I convex most of my users these days. I normally have done it by hand, with sandpaper and mousepad technique.

I have a few knives I use the belt sander on (including one of my nicer ones). But I am careful with it and cautious.

I have burned the tip on two knives while sharpening with the belt sander. The first two I ever tried (one is a designated thrower, that gets tons of abuse, and the other is the first knife I made......also the sharpest knife I have ever owned.....I did a much thinner convex than I put on any other knife, just to check if my ghetto heat treat was decent. Aparently the heat treat was ok, because no edge damage on normal stuff. It did roll ever so slightly when it made contact with bone..........the bone in my right hand thumb........not good).

The tips I burned are ok now, though, I just had to get past the steel that was affected.
 
bigfattyt the smooth round screwdriver is a great poor mans steel. just goes to show a little thinking outside the box can produce astounding alternatives. most formites are aware that the steels with grooves are no good for a fine edge. all butchers always used butcher slicks. the slick steels i've found in the last few years come from swiss or germany.thanks for a great touch up idea.
 
Dulling on cardboard depends on the steel type quite a bit.
Also, once the steel goes above 63-64HRC, average smooth steel, screwdrivers etc won't work anymore. You'd need ceramics or glass/borosilicate rods.
 
The original question was whether using a belt sander or even hand sharpening without oil/water would affect the heat treatment at the very edge. I didn't keep good enough records to able to tell here. I have burned a handful of knives sharpening them on the HF 1x30, but haven't done it in years. I generally don't use water to cool them between passes. Sharp belts make all the difference. These tests were done after sharpening on waterstones, followed by the Sharpmaker, so I'll have to check the belt sharpened edge this weekend.

I had previously discounted steeling, but I learned here that I was just using the wrong kind of steel. A smooth steel, and in this case, a flat one works wonders for maintaining an edge.

What steels dull on cardboard? This knife is stainless of some form, but I'd only be guessing if I gave a name to it. Apparently aluminum sheet doesn't dull knives much either. I'm up to 175 cuts without loosing hair shaving ability.
 
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