Can stropping remove significally amount metal?

Discussion in 'Maintenance, Tinkering & Embellishment' started by PlumasDePan, Sep 15, 2020.

  1. PlumasDePan

    PlumasDePan

    20
    Jul 21, 2020
    I used a wooden strop with 1 micron

    I give it like 20 strops in each side.

    And I feel like my knife got a bit smaller. Is this posible or it's my imagination?
     
  2. Sonnydaze

    Sonnydaze Gold Member Gold Member

    Jul 6, 2009
    It did get a bit smaller....a little, tiny, infinitesimal bit smaller...
    If you continue this for twenty yrs, the difference might be measurable.
    Just my opinion, of course.
     
    GABaus, rpttrsn, Terry M. and 5 others like this.
  3. MolokaiRider

    MolokaiRider Gold Member Gold Member

    Sep 13, 2017
    Different compounds and sprays cut differently.

    The lower grit cuts a bit more, the higher polish more.

    That said, it takes a significant number of passes to see your bevel retreating.

    You can however, see your edge being refined.

    It is a VERY small amount though. It would take a very long time, and thousands upon thousands of passes on your strop to see your knife shrink.
     
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  4. Rhinoknives1

    Rhinoknives1 Gold Member Gold Member

    Jul 1, 2013
    Buy a 10X loupe like a jewelry uses to watch your progress If you like? . I personally I use leather & green Chrome Compound. It works great & if it’s making your edge smaller, then you Knife isn’t hardened properly.
     
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  5. scdub

    scdub Basic Member Basic Member

    353
    May 29, 2004
    20 strops per side?

    It’s your imagination.
     
    GABaus likes this.
  6. kreisler

    kreisler

    593
    May 11, 2012
    factory grind lines say delica4 vg10 can be stropped away to mirror polish
    doesn't take too long
    more than 20 passes tho
     
    GABaus likes this.
  7. Depends on the compounds used on the strop and also how much compound the strop substrate can hold (which also depends on the substrate material itself).

    If you can SEE the polish quickly coming up on your bevels, that's a sign the strop & compound are working more aggressively.

    If your strop is blackening very quickly with use, that's another sign it's working more aggressively, removing more metal.

    Something like a hard-backed denim strop, used with a heavy application of buffing compound like aluminum oxide (commonly in the 5-15 micron range) can convex a blade's bevels pretty fast, while also bringing up a lot of polish. That's an undeniable sign that a strop of this configuration can remove metal pretty quickly.

    Having said all the above, a simple leather or wood strop with 1 micron diamond compound won't take a lot of metal away in just 20 passes or so. But it can make a noticeable difference in refinement & sharpness, if the edge was truly ready for stropping to begin with.
     
    Last edited: Sep 15, 2020
  8. Craig James

    Craig James

    182
    Oct 30, 2018
    No
     
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  9. Squid61

    Squid61

    96
    Aug 12, 2020
    I use powdered Al Oxide on my strops which is pretty aggressive and I see the strop turn dark so I know I'm removing metal but I don't think I'll live long enough to be able to measure the shrinkage.
     
  10. Diemaker

    Diemaker KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    612
    Apr 28, 2017
    With a 4 micron diamond loaded leather strop on really hard wear-resistant steels I limit my stropping to 3 or 4 passes, 1 micron and maybe 10 passes max. Any more and the apex disappears fast. IMO diamond on a strop is ONLY for super steels or ceramic, it is way too aggressive for normal steels.

    What I base this opinion on is the first time I tried polishing my bevel with a diamond loaded leather strop used with a guided sharpener on a 440ish blade. I was watching what was happening under a microscope and testing the sharpness by shaving my arm. First 5 passes, not much difference under the microscope but it shaved better. 20 passes and it was getting rather polished but it shaved worse and I had to shave at a steeper angle. 40 passes and it was getting nicely polished but it shaved poorly and the angle had doubled. Then I noticed that the bevel width had really shrunk. It had gone from about .04" to under .02". Even though I was stropping at the same angle that I had sharpened at it was convexing the bevel significantly.

    Even when used at the exact same angle as you sharpened the knife a firm leather strop only really works on the last .005" or so of the apex. If you strop to get a polished bevel you may very well/ most likely remove the apex, as in gone, disappeared, leaving a convex bevel.
     
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  11. Alberta Ed

    Alberta Ed

    Jun 29, 1999
    I am not convinced that stropping is effective on refining the edge of high carbide powder steels like S30V, S110V, etc. I've found those steels cut better with a toothy edge created by a coarse diamond hone (220 grit) and finished with an ultrafine diamond(1200 grit). A few light strokes on a steel works better on bringing that edge back after use in my experience; stropping doesn't seem to do much. High carbon steels with lower carbide volumes (1095 etc.) are easy to hone to a highly polished edge (great for woodworking) and may be refined with a strop (I use chromium oxide), but even then I'm not sure how effective that is. Old straight razors were considerably softer, I have read, around 40 HRC, and maybe stropping worked for those steels.
     
  12. Diemaker

    Diemaker KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    612
    Apr 28, 2017
    I found a photo of what 10 strokes with a 1 micron diamond loaded leather strop, using water as the carrier, does to a Maxamet blade after a 5 micron resin bond stone. I raised the angle of the strop 1/2 a degree which shows up half way through the bevel. The strop only polished the apex half. It doesn't look like much but makes it noticeably sharper feeling, just like going another grit on the stone progression. It push cuts cardboard nicely, for months :). For scale that bevel is about .06" wide.

    [​IMG]

    And here is what an over stropped bevel looks like. This is 440 or similar steel.

    [​IMG]

    This is what is started as, after the 8 micron resin bond stone.

    [​IMG]
     
    Last edited: Sep 15, 2020
  13. Squid61

    Squid61

    96
    Aug 12, 2020
    Stropping with any leather strop should be at slightly less than the actual bevel angle. If the stropping on leather is at the bevel angle and there is even a little pressure applied the apex will be rounded due to the indentation of the leather. This makes stropping a Scandinavian grind a bit trickier than most other grinds, the pressure must be very light, merely enough to polish, some have gone to Balsa rather than leather to prevent the potential edge roll.
     
  14. PlumasDePan

    PlumasDePan

    20
    Jul 21, 2020

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