Foam vs. honeycomb for carbon fiber sandwich

Discussion in 'Composites' started by birdus, May 17, 2018.

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  1. May 24, 2018 #41

    birdus

    birdus

    birdus

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    Thanks for that extra info, Bill. Jim Marske gave me some numbers regarding the strength I'll lose with the bends, so I'll probably just start out by building a simple test piece and do some static testing on it. That will also give me some practice with the building technique. I'll use Jim's calculations but add in enough extra Graphlite rods to make up for the loss in the curve. The test spar will probably just be a representative curve of the real one—maybe a 40" radius (or more) extended a couple feet on each side of the bend (maybe an 8-foot piece), which is about 30° where the landing gear mount. Jim told me that a 40" radius will lose about 7.5% in strength, so if I increased the number of Graphlite rods by, say, 10% in count, I'm thinking I'll be okay. The test piece should be enlightening.

    Jay
     
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  2. Jun 22, 2018 #42

    wanttobuild

    wanttobuild

    wanttobuild

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    AMT Composites
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    My apologies
    Ben
    H-Minus
     
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  3. Jun 23, 2018 #43

    harrisonaero

    harrisonaero

    harrisonaero

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    When in doubt, ask WWBD.... What would Burt/Bruhn do? :)

    Look in Bruhn D3.11 through D3.13 for the description and analysis methods for kick loads.
     
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