Page 1 of 6 12345 ... LastLast
Results 1 to 10 of 54
Like Tree58Likes

Thread: Suehiro Gokumyo 20K

  1. #1
    Senior Member Druid's Avatar
    Join Date
    Mar 2014
    Location
    Mysterious Adirondacks
    Posts
    773
    Thanked: 136

    Default Suehiro Gokumyo 20K

    Well, I finally broke down and bought one .. mostly to scratch an itch.

    This thing is a bear to flatten! I've been working on the back side to try to save the stamp. My DMT 325 is well worn, and not up to the task. Jamie, who knows this stone inside out, suggested 325 Wet or Dry. That has gotten me most of the way, but as we get closer and closer to the entire surface clean, the harder the going gets because so much surface area needs to be removed. I need a new DMT 325 anyway, but I'm wondering if I should also get the 220 DMT to speed things up?

    Any advice from those that have been in this boat?

  2. #2
    Senior Member Vasilis's Avatar
    Join Date
    Sep 2011
    Location
    Thessaloniki, Greece
    Posts
    885
    Thanked: 202

    Default

    Quote Originally Posted by Druid View Post
    Well, I finally broke down and bought one .. mostly to scratch an itch.

    This thing is a bear to flatten! I've been working on the back side to try to save the stamp. My DMT 325 is well worn, and not up to the task. Jamie, who knows this stone inside out, suggested 325 Wet or Dry. That has gotten me most of the way, but as we get closer and closer to the entire surface clean, the harder the going gets because so much surface area needs to be removed. I need a new DMT 325 anyway, but I'm wondering if I should also get the 220 DMT to speed things up?

    Any advice from those that have been in this boat?
    60-80-100 grit sandpaper, choose one of them, get more pieces if you think one is not enough and when flat enough, go for the DMT. You won't be in the same situation again for a long long time with normal use of the stone, so getting a diamond plate for a single use on a single stone that's one step coarser than the other one you are buying, it's counterproductive. I bet for the price of that diamond plate, the seller of the stone would be more than willing to flatten it himself.
    Druid and strangedata like this.

  3. The Following 2 Users Say Thank You to Vasilis For This Useful Post:

    Druid (08-27-2016), strangedata (08-30-2016)

  4. #3
    Senior Member blabbermouth
    Join Date
    Apr 2012
    Location
    Diamond Bar, CA
    Posts
    6,553
    Thanked: 3215

    Default

    Yes, they are hard, I used a CNTG 140 that got it flat then soothed with a 400 and 1k from CNTG.

    I did lap mine a few times, because it would leave a ragged edge. I ended up removing a bit of the top before it worked consistently well. I still have one corner that is low, and it will remain that way…

    The CNTG 140 plate at 35 bucks, I think, is a great stone for lapping, if you lap a lot. If yours is out of flat a lot, I would go at least to 220 or whatever it takes to get flat, then smooth with higher grits, don’t think it matters if you use Diamonds or Wet & Dry.

    I do refresh with a 400 then a 1k plate, just a few laps.

    You will have to experiment with pressure and laps to get the finish you want. It was not for me, the no brainer that folks rave about.

    It did take me a month or two to figure it out, for the stone to settle down, and get consistent edges from it. It is very easy, with some razors to take the edge too far and it will chip, so you have to find that balance point, based on your technique and pressure. The edge for me, is very reminiscent of film.

    Followed with .50 and .125um CBN it is a nice edge.

  5. The Following 3 Users Say Thank You to Euclid440 For This Useful Post:

    Druid (08-27-2016), ScoutHikerDad (08-28-2016), strangedata (08-30-2016)

  6. #4
    Senior Member blabbermouth JimmyHAD's Avatar
    Join Date
    Feb 2008
    Posts
    32,564
    Thanked: 11042

    Default

    That 20k made me glad I went for the Atoma 1200. The Atoma is superior to the DMT Dia-Sharp, and the Shapton DGLP in my experience. What I did with my 20k was start out with the 325 (D8C) and did the initial flattening, and then came in at 1/3 to go with the Atoma. The difference in effectiveness was startling the first time I did this. I went as far as I needed to go to have an unobstructed field for honing and no further. I figure I will get the rest of the grid over time, as I use the hone and continue to lap it. That corner is still got a long ways to go but I'm in no hurry.

    Name:  1Suehiro20K.jpg
Views: 532
Size:  28.5 KB
    Be careful how you treat people on your way up, you may meet them again on your way back down.

  7. The Following User Says Thank You to JimmyHAD For This Useful Post:

    Druid (08-27-2016)

  8. #5
    Senior Member blabbermouth
    Join Date
    Apr 2012
    Location
    Diamond Bar, CA
    Posts
    6,553
    Thanked: 3215

    Default

    Yup. Looks just like one of my corners, does not hurt anything and will waste too much stone to get it flat.

  9. The Following User Says Thank You to Euclid440 For This Useful Post:

    Druid (08-27-2016)

  10. #6
    Senior Member Druid's Avatar
    Join Date
    Mar 2014
    Location
    Mysterious Adirondacks
    Posts
    773
    Thanked: 136

    Default

    Thanks gents..

    Jimmy, that is about where mine is now. Does Atoma use a different grit system than the Dia-Sharp, or is it that much finer? My Dia-Sharp 325 must be severely worn, because it gives the G20 a reflective, glass-like surface! But it still cuts SuperStones like crazy!

  11. #7
    The Great & Powerful Oz onimaru55's Avatar
    Join Date
    May 2008
    Location
    Bodalla, NSW
    Posts
    15,595
    Thanked: 3747

    Default

    Quote Originally Posted by Druid View Post
    Thanks gents..

    Jimmy, that is about where mine is now. Does Atoma use a different grit system than the Dia-Sharp, or is it that much finer? My Dia-Sharp 325 must be severely worn, because it gives the G20 a reflective, glass-like surface! But it still cuts SuperStones like crazy!
    The Atoma have a raised surface so stiction is no issue unless you never rinse it while lapping.
    They also have a consistency of flatness that DMT doesn't have.
    Attached Images Attached Images  
    Last edited by onimaru55; 08-28-2016 at 12:46 AM.
    “The white gleam of swords, not the black ink of books, clears doubts and uncertainties and bleak outlooks.”

  12. The Following 2 Users Say Thank You to onimaru55 For This Useful Post:

    Druid (08-28-2016), strangedata (08-30-2016)

  13. #8
    Senior Member blabbermouth JimmyHAD's Avatar
    Join Date
    Feb 2008
    Posts
    32,564
    Thanked: 11042

    Default

    Quote Originally Posted by Druid View Post
    Thanks gents..

    Jimmy, that is about where mine is now. Does Atoma use a different grit system than the Dia-Sharp, or is it that much finer? My Dia-Sharp 325 must be severely worn, because it gives the G20 a reflective, glass-like surface! But it still cuts SuperStones like crazy!
    Quote Originally Posted by onimaru55 View Post
    The Atoma have a raised surface so stiction is no issue unless you never rinse it while lapping.
    They also have a consistency of flatness that DMT doesn't have.
    What Oz said. You can buy 3 D8C DMTs for the price of one Atoma 1200, but if I knew then what I know now I'd have only bought the Atoma. It is in a class by itself. Once you have the plate they sell replacement stick on diamond skins that are not as expensive as the whole plate. As Oz said, they are far more accurately flat than the DMTs.

    I've got the XX 120, the 325, 600, 1200, and 4000 DMT. Only the 600 is dead flat. The others are close, but it ain't horseshoes, or hand grenades, and flat is where it's at.
    Be careful how you treat people on your way up, you may meet them again on your way back down.

  14. The Following User Says Thank You to JimmyHAD For This Useful Post:

    Druid (08-28-2016)

  15. #9
    Senior Member
    Join Date
    Nov 2013
    Posts
    758
    Thanked: 104

    Default

    Only one thing. If you purchased your Gokumyo 20k from Tools of Japan (Stuart Tierney). he says emphatically that using a 1200 Atoma to lap it will void the warranty of the stone, due to particles of diamond breaking free of the plate and lodging in the hone. He recommends the Atoma 400 which I have used for nearly 2 years with great results. E mail him not me.

  16. #10
    The Great & Powerful Oz onimaru55's Avatar
    Join Date
    May 2008
    Location
    Bodalla, NSW
    Posts
    15,595
    Thanked: 3747

    Default

    People must have a lot of time on their hands to try lapping a new 20k with a 1200 Atoma.
    ScottGoodman, bobski and Druid like this.
    “The white gleam of swords, not the black ink of books, clears doubts and uncertainties and bleak outlooks.”

  17. The Following User Says Thank You to onimaru55 For This Useful Post:

    Druid (09-04-2016)

Page 1 of 6 12345 ... LastLast

Posting Permissions

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