Sealing the wooden airframe......

Discussion in 'Finishing Techniques' started by MadProfessor8138, Jan 3, 2019.

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  1. Jan 11, 2019 #41

    Rockiedog2

    Rockiedog2

    Rockiedog2

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    I don't varnish or paint hardware, never have. The finish on the AN hardware was as outa the box. The drag wire was stainless. The bolt holes were varnished with the same varnish and best I remember the shanks were also corroded; I looked back for pics to confirm that but don't have any so not gonna say that for sure. Pops is right if the inside of the holes aren't varnished the hardware will corrode in the hole. On repairs/rebuilds I always remove what hardware I can reasonably get to and inspect/finish the hole and the area behind any washers, plates, fittings etc(with epoxy for about the last 30 years or whatever it is)
    Beats me.
     
  2. Jan 12, 2019 #42

    TFF

    TFF

    TFF

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    Just admit it, you washed the bolts in battery acid. Moisture content could have been high, but what is more impressive is getting a chance to find it. I flew in a T-Craft one day; nice looking airplane. Because of flooding of our airport, planes were moved to another airport. It had to be tied outside and a big storm came through and the wing broke. Wing broke because the aft mout was rusted through under the fabric where you could not see. Hate the plane was damaged; would have hated it more if the wing came off in the air. As bad as it sounds, it was good the wing broke when it did.
     
  3. Jan 12, 2019 #43

    Pops

    Pops

    Pops

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    Sometimes what we think of as something bad happening is not.
     
    don january likes this.
  4. Jan 19, 2019 #44

    MadProfessor8138

    MadProfessor8138

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    I have a comment about hardware in contact with the wood....."WARNING" some of you may disagree with this.
    I know the moisture in the wood will eventually start attacking the metal bolts so anything that can be done to limit the bolts exposure to the humidity will help stop corrosion.
    What I've done in the past is seal the hole grain with varnish or epoxy....take the bolt and find a heat shrink tubing that is almost the same size as the shank of the bolt.
    Cut the tubing a little long....slide tubing on bolt.....use clear finger nail polish or a little rtv to seal under the end of tubing....heat the tubing and shrink it down extremely tight....clean off polish or rtv that was squeezed out....cut tubing off of threads and clean threads....and then use the bolt.
    The tubing adds almost nothing to the diameter of the bolt...the ends are sealed from moisture entering the tubing...and now anything in contact with the wood is protected by a plastic case so the moisture never touches the bolt.
    If you ever want/need to inspect the bolt just cut the tubing off and then reseal it to use again.

    Dont roast me for this guys....but I've used this trick many times and I've yet to ever have a corroded bolt.

    Kevin
     
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  5. Jan 19, 2019 #45

    Rockiedog2

    Rockiedog2

    Rockiedog2

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    Now I see why they call you MAD Professor

    Just kiddin:gig:

    But you won't mind if I don't do the same...
     
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  6. Jan 19, 2019 #46

    MadProfessor8138

    MadProfessor8138

    MadProfessor8138

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    Like I said.....everyone has their own techniques for doing things.
    This just happens to be a trick that a very old timer taught me when I was a kid.
    He was one of those guys that did things a little different from everyone else....but he never seemed to have any of the problems that everyone else constantly battled with.

    Kevin
     

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