Sharpening angle?

E

erik

Joined
Oct 11, 1998
Messages
4
Hi. I recently bought my first "good" knife, a Benchmade Ascent. I love the ATS-34 blade, it seems to cut anything I throw at it. But now I need to resharpen it. I plan on buying a sharpening set, and with it one can choose different angles at which to sharpen the blade. What are the advantages and disadvantages of narrow (like 20 degrees) as opposed to steeper angles? I use the knife for cutting everything from carrots to meat to rope to cardboard.
Also, what are the relative merits of the Lansky vs. the Spyderco Sharpmaker sets?
Thanks for your wisdom,
-Erik


[This message has been edited by erik (edited 11-01-98).]
 
erik-
If you want a Lansky, price it and I'll sell you the setup at 1/2 price. I have found that it doesn't work well with small knives and have moved over to the Spyderco Sharpmaker. I think it's a better choice for those of us who are free hand klutzes (not saying that you are, but *I* am). The Sharpmaker is especially good with the diamong sleeves...makes short work of excessively hard steel or dull knives.
Rich Lucibella
 
Erik:

The main advantage of a narrower bevel is that it cuts better. There's less steel to push through the target. Performance can vary drastically by shaving just a few degrees off the bevel angle.

The main advantage of a steeper bevel is that it's stronger. More metal behind the edge means it's less likely to roll or chip out. But it's harder to push all that metal through the target.

Common wisdom also has it that the steep bevel holds its edge for longer. I don't find this to be true at all, PROVIDED that the narrower bevel doesn't chip out or roll during your uses.

Assume the 2 copies of the same knife, except one has edge bevels at 17-degrees each and the other at 24-degrees. First of all, the 17-degree version will cut so much better that it has to get very dull before it goes down to the performance level of the freshly-sharpened 24-degree bevel. So the 17-degree version has a huge head start, performance-wise.

Now consider that as you cut with both knives, metal will wear off the very tip of the edge. As soon as the thick knife loses just a little metal, it stops cutting. The narrow knife can continue cutting even after a little metal loss, JUST BECAUSE IT'S NARROW. Consider a piece of paper, its edge are cut absolutely square. Can it cut you? Of course it can, for no other reason that it's narrow. How about a dull letter opener, if it's really thin, doesn't it still go through letters fine?

Here's the general rule:

The best hi-performance edge for your knife is the NARROWEST possible edge you can get that can still hold up to your hardest uses without rolling, chipping, or otherwise being damaged.

What that "best" edge angle is for your knife depends on blade shape, steel and heat treat, and how you will be using the knife.

The Benchmade Ascent is ATS-34, and Benchmade's heat treat on their blades is excellent. Considering the cutting uses you mentioned, I would definitely go to 20-degrees. In fact, if you find the edge is holding up great at 20-degrees, I'd consider going down even lower, to say 18-degrees.

Joe
jat@cup.hp.com
 
I just read an interesting tip on testing for edge sharpness and am wondering if this tip is good for all bevels. The tip came from Bob Schultz.

The tip is "Just rest the sharp blade on your hair, on the back of your head,(REST IT, on your hair.), if the blade is sharp it will stick in your hair if dull it will slide on hair. This is much safer than trying to shave hair off you arm". Mr. Shultz apologized for his bad spelling at the end of his post.

This tip does seem to work, but for all bevels?


 
Bob I tryed the test with the hair. I don't like it. Try it with a sharp knife and sure enough the knife did not slide, but then I tryed it with a knife that is not that sharp(will not shave hair)it said it was sharp too.
 
Shaving hair is a good job for a straight razor. A long lasting edge may not shave as well. IF you want to find a good all around angle and way of sharpening stop at a meat cutting plant.. If you want to chop stop at a hatchet factory. If you want to shave hair find a barber with a straight razor.
A meat cutting edge cuts the he** out of rope ect..

 
Darrel On sharping the more I learn the more cofused I get. In John Juranitch's book he said you can't have to sharp of an edge. I was willing to accept that he was wrong on some things like the kind of edge that will cut rope better but he came out of the meat cutting area and you say that a meat cuters edge is better for rope and if you are right then I have to start from square One? like I said I am confused. but when my knives will shave hair off my arm it sure seems to cut other stuff real good. maybe I will try some thing different. Still learning.
 
I've been doing some meat cutting lately. In this case, it's cooked meat (roast beef) instead of raw meat, though.

Long story short:

Polished (razor) edge: by far the worst slicer in cooked meat. Polished edges just don't slice well.

Serrated edge: A huge step up from the polished edge, but often snags and tears the meat, impairing accurate cutting.

Coarse edge: Sharpened on a DMT x-coarse diamond hone, and left that way. Best meat cutter by far, accurate like the polished edge, but aggressive like the serrated edge. No snagging or tearing, it just slices efficiently.

No need to be confused, just take out your kitchen knife and some hones, cook some steak, and start cutting. Polish one knife, leave the other very coarse. You'll understand much better after you experience it first hand.

If you want to read the full story,
you should check out the thread entitled "How to make your kitchen knives perform" on the Knife Design Function & Test Forum on knifeforums.com.
 
Rich -
I've had a Spyderco Sharpmaker for a couple of years, but - what is that 'diamond sleeve' you speak of? Where can I find something about it? Looked on the Spyderco page, they list it, but no info. Where can I get one? And why do you like it better than the two regular (course/fine) set?

------------------

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