Heat treating steel landing gear

Discussion in 'Tube and Fabric' started by Dana, Jun 30, 2010.

Help Support HomeBuiltAirplanes Forum by donating:

  1. Jun 30, 2010 #1

    Dana

    Dana

    Dana

    Super Moderator

    Joined:
    Apr 4, 2007
    Messages:
    8,482
    Likes Received:
    2,884
    Location:
    CT, USA
    Guess this should go in that "miscellaneous" section that doesn't exist yet, but..I do.

    I'm looking for input on an appropriate strength to heat treat a 4130 landing gear. Actually it's the tailwheel strut of my Kolb, which has bent a couple if times. I pulled it, heated it up, and bent it back straight again, but likely it'll just bend again (it's 5/8 diameter tubing). It is intended to flex for some spring action. Obviously I don't want to harden it to the point it gets brittle, but something higher than annealed or normalized might make it hold up better. But I have no idea what's a typical value for spring steel gear legs.

    -Dana

    Starve a feeding bureaucrat...vote Libertarian.
     
  2. Jun 30, 2010 #2

    BBerson

    BBerson

    BBerson

    Well-Known Member HBA Supporter

    Joined:
    Dec 16, 2007
    Messages:
    11,553
    Likes Received:
    2,159
    Location:
    Port Townsend WA
    Well annealed is about 65ksi. Normalized is about 80ksi. I would guess 125ksi-150ksi.
    How to do this?
    I think it is first heated cherry red for some time then quenched in used motor oil. Then it needs to be tempered. (heated to some lower heat for a time). I have heard that this temperature is what you get with a blueish/ purple color that appears on a polished clean area.
    BB
     

Share This Page

arrow_white