Author Topic: Trailer bunk support heights  (Read 155 times)

Offline chimerakc

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Trailer bunk support heights
« on: December 11, 2017, 09:57:12 AM »
So I replaced the bunks and now see that the middle support on each side is several inches lower than at the ends. And the old lumber was bowed in reflecting that.   So the new lumber of course cant be attached to the middle supports until the boat gets on - and I assume its shape and weight will bend the lumber down so I can screw the supports into the bunks in the middle.

Does this sound right?   I just cant picture the shape of the hull along the bunks that results in this.   I am resisting my temptation to raise the middle posts so the new wood is all attached before the boat gets on there the first time.   When it goes on it will be in the spring and stay there 6 months just fyi.

Thanks

Offline rmotley

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Re: Trailer bunk support heights
« Reply #1 on: December 11, 2017, 08:36:21 PM »
We used a ratchet strap to pull the center down and bolted to the support - think we used standard treated decking boards - the weight rides on the keel rollers

Offline brackish

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Re: Trailer bunk support heights
« Reply #2 on: December 11, 2017, 10:37:33 PM »
yes that is right, don't raise the center bunk posts, jack the bunk boards down with a ratchet strap and connect.  It will conform to the shape of the hull.  Somewhere on this site, I've posted the dimensions with pictures, unfortunately the pics where photobucket and are gone, but the dimensions ares still good or at least the relative difference between the three bunk supports.

Offline chimerakc

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Re: Trailer bunk support heights
« Reply #3 on: December 12, 2017, 05:01:42 PM »
Thanks for these replies - I kinda forgot the real weight is on the rollers.   
With my trailer the bunk supports are attached with pretty thick but shallow wood screws - if you remove the ratchet I wonder if they wont pull out?    Would it harm anything to just load the boat and attach the screws to the bunk after its weighed the boards down?

Offline Cruzin

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Re: Trailer bunk support heights
« Reply #4 on: December 12, 2017, 07:17:27 PM »
Attached are the measurements for a Magic Tilt trailer set-up from Com-pac. Obviously all trailers are a little different, but these worked for me with a different brand of a trailer.

Good luck!

Dale
” Some people never find it, some… only pretend,  but Me; I just want to live happily ever after, now and then.”  Jimmy Buffett

Offline rmotley

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Re: Trailer bunk support heights
« Reply #5 on: December 13, 2017, 04:57:32 PM »
Thru bolted with carriage bolts (rounded side) under indoor / outdoor carpeting scraps facing the hull - nuts, lock washers pointing toward the ground - can't imagine screws holding long term

Offline chimerakc

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Re: Trailer bunk support heights
« Reply #6 on: December 14, 2017, 05:06:15 AM »
Thanks again guys.  I am tempted to in the spring just load the boat and let it bend the boards down and then put the screws that were there back in.   I only move the trailer 100 yards back and forth to our docks twice a year so not too concerned with it banging around too much on the supports.   But I will see how the ratchet thing goes too - yes I agree the supports should be through bolted, not screwed to the wood.