Quantcast
Edge retention
Page 1 of 2 12 LastLast
Results 1 to 10 of 17

Thread: Edge retention

  1. #1
    Senior Member

    Join Date
    Feb 2011
    Location
    San Diego, CA
    Posts
    4,227

    Edge retention

    I generally use pretty fine edges so they get dull quicker but they seem to respond better to frequent stropping than coarser edges. On the occasion that I actually do compare edge retention, I'm basically talking about how fast a highly refined edge loses that feeling of ultimate sharpness which is generally pretty quick. If I was looking to see how long I could cut onions without smashing them, my impression would likely be totally different and the geometry of the blade/edge would start to take over. I'm wondering what everyone else is evaluating when determining edge retention.

  2. #2

    Join Date
    Apr 2011
    Location
    Near Seattle, WA
    Posts
    290
    In my opinion, Bill Burke's knives have one of the best blades for edge-retention with his triple quenched 52100. I believe that Chef Niloc did a review of one of Bill's knives recently, and made comment on that so maybe he can chime in here again and compare a bit how he judged that. One test I am aware of is the cutting of rope on a digital scale. They cut until it requires too much (of a pre-determined) pressure. Maybe one knife cuts 165 - 1" ropes at 20lbs pressure while some other knife cuts only 51 at that pressure.
    -M

  3. #3
    Quote Originally Posted by Michael Rader View Post
    ...
    One test I am aware of is the cutting of rope on a digital scale. They cut until it requires too much (of a pre-determined) pressure. Maybe one knife cuts 165 - 1" ropes at 20lbs pressure while some other knife cuts only 51 at that pressure.
    -M
    That is the test that I would like to do and I think it is a perfect test to compare performance of different knives in approximately same hardness range and sharpened to the same level. Moreover, since ropes vary in their composition, it's good to buy a lot of one kind and keep using the same rope when comparison with previous tests is important.

    M


    "If there’s something worth doing, it’s worth overdoing.” - An US saying.

    If my KKF Inbox is full (or not), please contact me via Email: anvlts@gmail.com

  4. #4
    Senior Member Cadillac J's Avatar
    Join Date
    Mar 2011
    Location
    Detroit
    Posts
    621
    Really good point TK, and as a home cook and avid sharpener, I share similar views as you regarding retention.

    There is just this point where I feel my edge needs to be invigorated with stropping or a polishing stone as I crave that freshness, but if left alone I know that it would still cut for a long time(which it pained me to test previously), and would be considered very sharp thereafter by many other people. Once again, I think it comes down to what you consider to be sharp and your preference of how you want your knife to feel when cutting.

    I will strop a fresh edge after only two(sometimes just one) cutting session to preserve that feeling on the initial cut, even though the edge doesn't really need it at all. Why are we so damn crazy?

  5. #5
    Quote Originally Posted by Michael Rader View Post
    In my opinion, Bill Burke's knives have one of the best blades for edge-retention with his triple quenched 52100. I believe that Chef Niloc did a review of one of Bill's knives recently, and made comment on that so maybe he can chime in here again and compare a bit how he judged that. One test I am aware of is the cutting of rope on a digital scale. They cut until it requires too much (of a pre-determined) pressure. Maybe one knife cuts 165 - 1" ropes at 20lbs pressure while some other knife cuts only 51 at that pressure.
    -M
    I thought Colin reported the DT ITK output the Burke. I can't find it though.

  6. #6
    Canada's Sharpest Lefty Lefty's Avatar
    Join Date
    Mar 2011
    Posts
    5,116
    What would you know about the itk? Jk!
    For the rope test, is the rope laid across a cutting board or tethered at both ends, in mid air? If it's the latter, wouldn't length of rope even play a part in how much force is needed to cut through it?
    09/06

    Take a look around at: www.sharpandshinyshop.com

    Email me at: tmclean@sharpandshinyshop.com

  7. #7
    Senior Member stevenStefano's Avatar
    Join Date
    May 2011
    Location
    Norn Iron
    Posts
    1,391
    The way I test if the knife is sharp enough is to cut a tomato in half and put it on a chopping board cut side down. I then try and cut through the skin, and depending on how much pressure is needed, I know how sharp it is. When I do it my Masamoto always does it a little better than all my VG10 knives

  8. #8
    Quote Originally Posted by Lefty View Post
    What would you know about the itk? Jk!
    For the rope test, is the rope laid across a cutting board or tethered at both ends, in mid air? If it's the latter, wouldn't length of rope even play a part in how much force is needed to cut through it?
    The rope weight is relatively insignificant, especially since the stopping point is difficult to pinpoint, and the weight of the rope should be about the same across the test. Anyway, as long as the test is the same each time the results should be comparable. However, due to differences in rope and each tester the rope test is difficult to compare from multiple people. Another problem with the test is that thinner knives do much better. In part this is because the thinner knife requires less to begin with, and for another the thin knife cuts better when dull. This demonstrates the superiority of thin knives in many situations, but can be misleading when comparing different steels, heat treatments, or knives made for different or very specific applications. One more problem is that rope isn't necessarily a realistic test for knives that will ultimately be cutting meat and vegetables.

  9. #9
    Canada's Sharpest Lefty Lefty's Avatar
    Join Date
    Mar 2011
    Posts
    5,116
    Great point Larrin!
    Thin would be a huge advantage in a test like this, which really makes testing steel types head to head difficult.
    One steel might be better than another at a more obtuse angle/ thicker blade, while the opposite could be true for another. Not to mention, different steels respond differently to toothier finishes, etc.
    I think steel type alone is less Important than the knife as a whole. In other words, we should really worry about which knife we all prefer and find has good attributes in our hands.
    09/06

    Take a look around at: www.sharpandshinyshop.com

    Email me at: tmclean@sharpandshinyshop.com

  10. #10
    Senior Member
    Join Date
    Apr 2011
    Location
    Singapore
    Posts
    750
    For me, edge retention = how long I can get away without sharpening on a stone and still go through 6 cases of tomatoes without juicing them.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •