Page 1 of 2 12 LastLast
Results 1 to 10 of 17

Thread: how to flatten honing stones

  1. #1

    Default how to flatten honing stones

    I have what appears to be an Arkansas fine stone that appears to have a dip in the middle of the stone that isn't allowing me to hone the full surface of larger parts. Any suggestions on how to get it flat again?

    Lj

  2. #2

    Default

    When I posed that question to a toolmaker/shop teacher he got out a couple tins of loose silicon carbide abrasive and had me sprinkle it on a flat ground plate with a little oil and do the figure 8 lap process to flatten the stone again. It worked fine for me on that occasion.

    I haven't looked for a source for the abrasive lately, but one used to be able to get valve grinding compound in various grit sizes. Maybe still can. McMaster Carr would be a good place to hunt.
    .
    "Opportunity is missed by most people because it is dressed in overalls and looks like work." Thomas Edison

  3. #3
    Join Date
    Jan 2010
    Location
    Kansas City area
    Posts
    3,039

    Default Flatten Stone

    Maybe rub it on a diamond hone. I haven't tried that, but it seems logical.

  4. #4
    Join Date
    Aug 2010
    Location
    Flint, Michigan
    Posts
    273

    Default

    Over the years I've found and flattened many old bench stones. One way that works is to do it outside on the concrete walk, patio, etc. where it's rough enough to get a bite, slosh water on and rub til the wear is even. The concrete will smooth after a bunch of stoning, though, and not cut as rapidly. This will get you pretty close, but not truely flat, so the next step is emery paper. Belt sanders are the fastest, but flattening a stone will pretty well use up a belt and isn't the most economical of choices. Paper taped to a flat surface and used wet is effective, albeit slow and tedious, and depending on the stone size, several sheets may be required. A plate glass 1/2 inch thick is my choice of flat surface. Over time the grit has scratched it severly, but still it's plenty flat enough for this kind of job.
    In past times, the large grindstones were flattened with tools that remotely resembled a curry comb for horses that had steel teeth filed into the rubbing surface to cut away the stone. Of course, those were largely sandstone and wore more quickly than a hard stone. Makes me wonder if a tightly bundled stack of old hacksaw blades might............. ?

  5. #5
    Join Date
    Jun 2006
    Location
    Austin, Texas
    Posts
    15,651

    Default

    Quote Originally Posted by Toolguy
    Maybe rub it on a diamond hone. I haven't tried that, but it seems logical.
    Someone here recommended that, and I tried it -- works great.
    "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

  6. #6
    Rosco-P Guest

    Default

    Search function is your friend. This has been discussed several times over the years. Here's one thread: http://bbs.homeshopmachinist.net/sho...ttening+stones

  7. #7
    Join Date
    Jun 2003
    Location
    Columbus, Ohio
    Posts
    2,349

    Default

    I keep my old bench grinder wheels, the sides are good for cleaning and flattening out smaller stones. I have a part of one laying on my bench and with a little oil or sometimes a thin cleaner, I rub a figure eight with the stone on the side of the broken wheel. Mind you, this is not on the grinder or under any type of power.

    rock~
    Civil engineers build targets, Mechanical engineers build weapons.

  8. #8
    Join Date
    Feb 2006
    Location
    Midwest City, Oklahoma
    Posts
    418

    Default

    A belt sander works wonders on a misshapen stone. I've fixed the surfaces of most of my stones this way. I light boil in some soapy water a time or two cleans up a clogged stone nicely =)

    Hope that helps some!

  9. #9
    Join Date
    Aug 2004
    Posts
    438

    Default Hire a kid

    Fine Woodworking had a letter several years ago from a guy who hired a 5 year old with a tricycle. He tied a string around the stone and paid the kid to drive his tricycle in a circle on his driveway at a nickel a circle.

    The string with the stone was tied to the back of the tricycle.

    Probably can't do that anymore, what with the 1099 & I-9 tax and immigration forms as well as the liability insurance.

  10. #10
    Join Date
    Oct 2002
    Location
    Bremerton Washington
    Posts
    4,960

    Default

    I tried the sidewalk thing and it didn't really work. There was some wear on the stone but it didnt get flat in a controlled wat. Silicon carbide as a dressing stone didn't work very well either.

    What DID work was an extra-coarse diamond/nickel plated "stone" such as marketed by DMT. When the "India" stone is gently rubbed on the DMT stone under flowing water sediment was generated and the stone was soon flattened and restored to a like new tooth. The finer the diamond stone the smoother the dress on the India stone which if too smooth leads to near zero cutting.

    When I say "India" stone, it's habutual. I prefer the Norton "abrasive file" line that used to be called "India". In this post I refer to most any aluminum oxide bonded abrasive used in stick or rectangular form for sharpening tools, dressing burrs, touching up details in hardened steel, etc whether used by woodworkers or machinists and tool makers.

    I use my India stones for dressing scraped surfaces and I want a slight convexity. The DMT extra coarse cleans the scrubbed in cast iron swarf, removes the hollow, and restores the "tooth" - the cutting roughness. Your mileage may vary. You may desire a smooth stone that barely cuts. Regardless there are several diamond plated stone sellers out there and their products will work if selected properly.

    I suggest you get a new diamond plated stone for dressing and use it for no other purpose. Sharpening steel on them blunts the diamond and greatly reduces its effectiveness as an shop stone dressing tool.

    After you use an extra coarse diamond stone for tuning up your Al2O3 stone collection under flowing water, you will never go back to concrete.
    Last edited by Forrest Addy; 04-07-2011 at 01:59 AM.

Posting Permissions

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