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Annealing Aluminum Tubing

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  • #1

    Annealing Aluminum Tubing

    I have formed most of my fuel and brake lines. Given that they are all well supported is it necessary to anneal them? I am using 3003 Versatube for most lines. I am curious if they are prone to cracking if I don't do the annealing. It is my understanding that most builders don't anneal them. Is this correct?

    The reason I am asking is because I found this text in Bingelis' Firewall Forward:

    Screenshot 2022-10-09 230029.jpg
    Attached Files
    Bearhawk "XHawk" Patrol, O-360, Trailblazer 80", tubeless 26" Goodyears, Stewart Systems. See XHawk Build Log.
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  • #2
    The 3003 alloy is soft, so unless you really did some severe bends and fussed with them a lot, As long as you used the proper techniques and not have any dead-straight runs I wouldn't worry about it.

    Comment

    • #3
      I take this as a data point. Thanks alaskabearhawk.
      Bearhawk "XHawk" Patrol, O-360, Trailblazer 80", tubeless 26" Goodyears, Stewart Systems. See XHawk Build Log.

      Comment

      • #4
        Originally posted by alaskabearhawk View Post
        The 3003 alloy is soft, so unless you really did some severe bends and fussed with them a lot, As long as you used the proper techniques and not have any dead-straight runs I wouldn't worry about it.
        By dead-straight do you mean unsupported runs of straight tube? For example, if I support a straight 3/8 tube every 16 inches (per AC 43.13) in a 6 foot run, I should be ok, right?

        Comment

        • #5
          Originally posted by podo View Post

          By dead-straight do you mean unsupported runs of straight tube? For example, if I support a straight 3/8 tube every 16 inches (per AC 43.13) in a 6 foot run, I should be ok, right?
          No, not really. This is from AC 43-13B, Para 8-31c., italics are mine:

          c. Alignment. Locate bends accurately so
          that the tubing is aligned with all support
          clamps and end fittings and is not drawn,
          pulled, or otherwise forced into place by them.
          Never install a straight length of tubing between
          two rigidly-mounted fittings. Always
          incorporate at least one bend between such fittings
          to absorb strain caused by vibration and
          temperature changes.

          You need to have some sort of bend between fittings on a straight run. On this page of my kitlog, the first and third pics show what is a dead-straight run and the bend necessary to absorb vibraion and changes in temperature.

          http://www.mykitlog.com/users/display_log.php?user=yeeeha&project=527&category=8690&log=282733&row=7


          Hope this helps clarify...

          Comment

          • podo
            #5.1
            podo commented
            10-11-2022, 06:41 PM
            Editing a comment
            Thanks, Paul. That makes it clear. It seems your link is broken but I think this is the page to which you're referring. http://www.mykitlog.com/users/displa...g=282733&row=7
          • alaskabearhawk
            #5.2
            alaskabearhawk commented
            10-12-2022, 12:50 AM
            Editing a comment
            Yep, that's it! I don't know why it won't work, but thanks so much for posting the correct one.
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