Proper Strength of Plywood

Discussion in 'Wood Construction' started by blane.c, Jun 7, 2019.

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  1. Jul 19, 2019 #21

    TerryM76

    TerryM76

    TerryM76

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    Any particular advantages for choosing marine plywood other than cost?
     
  2. Jul 19, 2019 #22

    tdm3

    tdm3

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    I assume Sisler called that out because it was cheaper and more than adequate within his design. I'm using it because he particularly called for it, it's cheaper and it's more readily available.

    David
     
  3. Jul 19, 2019 #23

    Dan Thomas

    Dan Thomas

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    The 2x4 or 2x6 or whatever was the dimension of the board when it was cut from the log. Rough boards. When they were run through the planer they were reduced to 1-5/8" x 3-5/8" up until around the late 1960s or so, and then they were reduced to the dimensions we see now. Rough-cut wood now is nowhere near the old 2x4 etc. dimensions, since it wastes too much wood. Good trees are disappearing, so the processors have to minimize the waste. That's why we see rough saw marks on some areas of planed boards, and one or two corners with bark still on them.

    My Dad and Grandpa were lumber-mill guys. Grandpa was a lumber grader. I used to watch him grading lumber as it went by on the green chain, and the stuff he marked "cull" (junk) is now what I see being sold as construction #2 or better. There were a lot of "clear" boards when I was young: no knots at all, nice straight grain. Lots of big trees. I miss that stuff.
     
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  4. Jul 21, 2019 #24

    TerryM76

    TerryM76

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    Thanks David. Do you know if there is a significant weight difference between the two?
     
  5. Jul 21, 2019 #25

    Little Scrapper

    Little Scrapper

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    I bought a full sheet of Meranti and tested it. It's brittle. It snaps very easily. I would avoid it for anything in a aircraft where structural integrity matters.
     
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  6. Jul 22, 2019 #26

    tdm3

    tdm3

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    Terry, my understanding is that both mahogany and birch would be heavier in the same thicknesses but I have no idea how much difference.
    David
     

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