Register now to get rid of these ads!

Soften Hardened Steel

Discussion in 'The Hokey Ass Message Board' started by iammarvin, May 16, 2013.

Thread Status:
Not open for further replies.
  1. iammarvin
    Joined: Oct 7, 2009
    Posts: 1,197

    iammarvin
    BANNED
    from Tulare, Ca

    Need help on making hardened steel soft enough to drill through. What I am making is purely cosmetic, so no structural problems to worry about.
     
  2. blitz
    Joined: Jun 15, 2009
    Posts: 139

    blitz
    Member

    get it real hot and let it cool slowly.
     
  3. F&J
    Joined: Apr 5, 2007
    Posts: 13,223

    F&J
    Member

    Red hot, let cool slowly. That's all I got.
     
  4. Bury it in dry sand, that will prolong the cooling.
     

  5. DeucePhaeton
    Joined: Sep 10, 2003
    Posts: 1,003

    DeucePhaeton
    Member

    What they said works most of the time. Bury it in the sand will help slow the process as long as there isn't much moisture in the sand. We used Mica in the factory.
    If it happens to be air hard tool steel, you're in trouble.
     
  6. F&J
    Joined: Apr 5, 2007
    Posts: 13,223

    F&J
    Member

    speedy dry works real good as insulation when slowing the cooling rate.
     
  7. lukey
    Joined: May 27, 2009
    Posts: 668

    lukey
    Member

    I had a guy ask me this before...I told him to soak it in water over night and it would soften it...he came back a few days later saying it didn't work to well...


    Posted from the TJJ App for iPhone & iPad
     
  8. iammarvin
    Joined: Oct 7, 2009
    Posts: 1,197

    iammarvin
    BANNED
    from Tulare, Ca

    This is a used farming disc, if that helps. Last night I heated one spot red hot and tried to drill it, "tried" is the word, tough stuff.
     
  9. get it cherry red with a rosebud
     
  10. jcapps
    Joined: Dec 30, 2008
    Posts: 473

    jcapps
    Member
    from SoCal

    been successful with a carbide bit, what size hole
     
  11. F&J
    Joined: Apr 5, 2007
    Posts: 13,223

    F&J
    Member

    Ultra slow drill press that can press hard.

    Also, if you custom grind the drillbit, it can help.

    Hard to explain without pictures, but a normal bit is sharpened to be like a snowplow blade, that digs under... if you make the bit edge like a flat push, almost 90 degrees to the thing you are drilling.

    Lots of cut oil, real slow, lots of pressure.
     
  12. iammarvin
    Joined: Oct 7, 2009
    Posts: 1,197

    iammarvin
    BANNED
    from Tulare, Ca

    7/16, slowest speed on the press,approx 300, a lot of cutting fluid, one hole went like normal steel, the other two ate up bits.
     
  13. DouginIA
    Joined: Jan 27, 2013
    Posts: 13

    DouginIA
    Member

    I use masonry drill bits to drill hardened tool steel with. Run your drill at about the same speed that you would drill mild steel at. Don't spray coolant ohe drill bit or part that you are drilling the cold shock from the coolant it will shatter the carbide tipped drill bit,a steady blast of air works good,don't get the drill bit to hot but some heat seems to help when drilling hard steel
    It is also a good idea to clamp a piece of mild steel under your part,other wise your bit will most likely shatter when the tip of the drill breaks through the hardened steel and have everything clamped solid to your drill press table.
     
  14. Engine man
    Joined: Jan 30, 2011
    Posts: 3,476

    Engine man
    Member
    from Wisconsin

    I would heat it up cherry red and slowly back the torch away letting the color go to dull red then blue then grey. Let it slowly cool to room temperature from there. Why not torch the holes?
     
  15. iammarvin
    Joined: Oct 7, 2009
    Posts: 1,197

    iammarvin
    BANNED
    from Tulare, Ca

    Yessss....torching the holes is an option, but I need to ummm "seat" them for lack of a better term.
    So I will heat the disc ( where the shanked (?) ) where the bolt will go to make it flush with the disc.
    Does that make any sence???
     
  16. What about torching bigger holes, welding in nuts and "seating" them in the nuts?
     
  17. iammarvin
    Joined: Oct 7, 2009
    Posts: 1,197

    iammarvin
    BANNED
    from Tulare, Ca

    Trying to keep the top of the counter sunk bolts flush with the top of the disc.....They will bolt to a rim....Moon disc style.
     
  18. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,521

    gimpyshotrods
    ALLIANCE MEMBER

    Please tell me this is an art project.
     
  19. Those discs are pretty damn heavy if this is going on a car to actually drive :eek:
     
  20. Rickybop
    Joined: May 23, 2008
    Posts: 7,257

    Rickybop
    Member
    from Michigan

    Won't it make your car tend to plow into the corners?
     
  21. 41GASSER
    Joined: Aug 2, 2009
    Posts: 188

    41GASSER
    Member

    I worked at a heat treating shop for many years. I suspect the disc is a case hardened 1040 or similar material. A disc has to be very hard or the abrasive soil will quickly wear it out. Annealing it will require a 1600 f and controlled slow cooling. If your wifes not home heat it with a torch and throw it in the oven at its highest setting. Shut the oven off and let it cool off. Cheaper than taking it to the local heat treating shop.
     
    Last edited: May 17, 2013
  22. I agree that its probably case-hardened. The base steel is a relatively softer steel, so bringing it up to 1600 F may render it as soft as dog-poo.

    I would drill it with cobalt or Ti coated drills, using a water soluble coolant in a spray bottle (if you have it). Motor oil will work too with a brush. If you are using a drill press, hold the part in a vise or clamp it to the table.

    Using a conservative cutting speed of 60, yout max RPM for the final drilling is around 540. I would spot the hole with a spotting drill or center drill, make the spot a little bigger than your finish size of .437.

    Start with a smaller drill (~ .250) and work up in steps to the final size. Run the .250 drill at around 900 RPMs. I have a shitload of drill around, so I'd step it at .250, .343, .406 and .437 diameters.

    Bob
     
  23. THX_138
    Joined: Nov 11, 2006
    Posts: 290

    THX_138
    Member

    What about hitting it with a torch until cherry red and then quickly putting the drill to it while it's still glowing?

    I have no clue what the results may be, but my curiosity may overcome me enough to try it myself just to see what happens.
     
  24. mcmopar
    Joined: Nov 12, 2012
    Posts: 1,650

    mcmopar
    ALLIANCE MEMBER
    from Strum, wi

    If this is a on a disc it is a good steel, do the oven trick.
     
  25. rustednutz
    Joined: Nov 20, 2010
    Posts: 1,580

    rustednutz
    Member
    from tulsa, ok

    Rickybop, that's a good one --- plow into the corners!!!!! I've used the wife's oven many times for my shop projects to slow the cooling process, but, never when she's home.
     
  26. There probably is not enough carbon in the base steel to get any advantage out of a heating process. And if you're not sure of the alloy, be conservative with what you do. The actual depth of case hardening goes around .040-.062.

    Years back, I had made a tool with what was supposed to be vega (A2) tool steel. After heat treat, we ran a quick Rockwell test on it prior to annealing, it was down to around a Rc of 28, expected hardness should have been in the Rc 52-56 range.

    So if you want to go with the oven processing, toss in a couple of sheets of cookies to the exercise won't be totally futile.

    Bob
     
  27. mashed
    Joined: Oct 15, 2011
    Posts: 1,474

    mashed
    Member
    from 4077th

    Will dull the drill bit PRONTO.
     
  28. iammarvin
    Joined: Oct 7, 2009
    Posts: 1,197

    iammarvin
    BANNED
    from Tulare, Ca

    This shit is HARD! Heated to red hot, cooled - no luck. Tried to drill it red hot - no luck. Red hot, let cool a coupla times - no luck. Want a nicer hole then what the torch will do.
     
  29. Big_John
    Joined: Mar 28, 2006
    Posts: 333

    Big_John
    Member
    from Upstate NY

    Find a waterjet shop to make the hole. It'll probably be cheaper than you think.
     
  30. Go with the water jet, you have something more than case-hardened.

    Did you run a file across an edge of it? That is the best and fastest indication of how hard a material is. If it digs in a lot, you have soft material. If the file skates off it and makes a minimal mark, you have very hard material.

    Bob
     
Thread Status:
Not open for further replies.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.