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  • #16
    Originally posted by JohnE View Post
    The one at the factory was on that setup for a very short time period, relatively speaking to boat storage, so I wouldn't go by that. The question I'd ask is how evenly is that 500 square inches supporting the weight. Looks like most of the weight is supported at the connection to the lift.
    I apologize, sometimes my logic comes across incorrectly in my typing. My boat was only on the lift long enough to see how the bunks looked......15 minutes maybe (I didn’t even lift it completely out of the water). That’s why I referenced the factory picture.

    I agree with you on the load distribution, so I went way above the recommendation. I have around 1,200 square inches. I could be wrong but I don’t think I’m over the 15 pounds per square inch maximum anywhere on the hull.

    The part that concerns me is whether the lumber is up to the challenge...so to speak.

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    • #17
      Keep in mind that a lift doesn’t have to be as good as a trailer. When trailering the boat there are dynamic forces which put way mor force on the bunks. Probably double. Therefore lift bunks can be smaller than trailer bunks.
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      • #18
        I had the exact same issue with the bunks bowing on my boat and what if figured out is that the step up on the hull aft kept the rear of the boat off the bunks which put all the weight forward. I put a 1 x 8 on top of the bunks to support the step up an the bow disappeared. Despite different boats I would wager this would solve your issue. (It looks to me like you have hull that steps up?). There is a picture somewhere in here if you search my posts.

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        • #19
          Bare wood is fine - seriously. People freaking out that it's not carpeted should maybe look at the scuff marks that pulling onto a trailer leave. I would have heavier duty wood though.

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          • #20
            I would switch to pressure treated wood, then install the carpet.

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            • #21
              Originally posted by KWSC View Post
              Keep in mind that a lift doesn’t have to be as good as a trailer. When trailering the boat there are dynamic forces which put way mor force on the bunks. Probably double. Therefore lift bunks can be smaller than trailer bunks.
              Meh. Improper bunk placement can warp your hull. I spent WAY too much time trying to adjust an off the shelf v drive adjustable cradle and I’ll never go back.
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              • #22
                ^^^^That's Awesome^^^^

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                • #23
                  There are several factor that go into determining the allowable deflection of a 2x6. The major factors being the usage condition, wood species, the moisture content of the wood, and the distance between the supports. Using typical construction conditions (think house construction), southern pine, moisture greater than 20%, and a span of approximately 10ft between supports, you can get a deflection a little over 2 inches without over stressing the wood. Keep in mind that your usage is outside of normal usage conditions (submerged in water for hours at a time) so the relative strength will be lower and the deflections can be higher. It's rough, but I hope that helps some.

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                  • #24
                    Originally posted by MC25 View Post
                    Meh. Improper bunk placement can warp your hull. I spent WAY too much time trying to adjust an off the shelf v drive adjustable cradle and I’ll never go back.
                    That's how you do it

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                    • #25
                      That is cool Aric.

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                      • #26
                        Originally posted by TXSkingPE View Post
                        There are several factor that go into determining the allowable deflection of a 2x6. The major factors being the usage condition, wood species, the moisture content of the wood, and the distance between the supports. Using typical construction conditions (think house construction), southern pine, moisture greater than 20%, and a span of approximately 10ft between supports, you can get a deflection a little over 2 inches without over stressing the wood. Keep in mind that your usage is outside of normal usage conditions (submerged in water for hours at a time) so the relative strength will be lower and the deflections can be higher. It's rough, but I hope that helps some.
                        Originally posted by epnault View Post
                        That's how you do it
                        Originally posted by Maristar210 View Post
                        That is cool Aric.
                        Aric finally getting the respect he deserves lol, whole forum was hur dur when he posted originally:
                        https://teamtalk.mastercraft.com/showthread.php?t=83128
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                        • #27
                          I missed that thread. Ingenious!!!

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                          • #28
                            Originally posted by TXSkingPE View Post
                            There are several factor that go into determining the allowable deflection of a 2x6. The major factors being the usage condition, wood species, the moisture content of the wood, and the distance between the supports. Using typical construction conditions (think house construction), southern pine, moisture greater than 20%, and a span of approximately 10ft between supports, you can get a deflection a little over 2 inches without over stressing the wood. Keep in mind that your usage is outside of normal usage conditions (submerged in water for hours at a time) so the relative strength will be lower and the deflections can be higher. It's rough, but I hope that helps some.
                            I appreciate all the responses in this thread, however...this is exactly what I was looking for. Thanks a lot TX!

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                            • #29
                              Originally posted by pmikler View Post
                              I had the exact same issue with the bunks bowing on my boat and what if figured out is that the step up on the hull aft kept the rear of the boat off the bunks which put all the weight forward. I put a 1 x 8 on top of the bunks to support the step up an the bow disappeared. Despite different boats I would wager this would solve your issue. (It looks to me like you have hull that steps up?). There is a picture somewhere in here if you search my posts.
                              Hey, good idea on the 1x. I’ll give that a try. Thx

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                              • #30
                                Originally posted by LDA6339 View Post
                                Aric finally getting the respect he deserves lol, whole forum was hur dur when he posted originally:
                                https://teamtalk.mastercraft.com/showthread.php?t=83128
                                “Whole forum”?..... Whoa, easy now.

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