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swim platform brackets wearing?


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two pieces to the brackets securing the swim platform. wear is really noticeable on the piece attached to the hull. replaced one of the VERY pricey hull side brackets last year and it's already worn enough to be a concern. the wear shaves the very top lip of the bracket into a razor sharp edge.

  • anyone else having similar problems?
  • am i getting more wear because i didn't replace BOTH the hull mounted piece AND the platform mounted piece as a set?
  • are the new hulls using a similar set-up or something more robust?
  • if i spend the $$ to replace should i migrate to the newer design?

post-85-0-21740400-1354028522_thumb.jpgpost-85-0-30795000-1354028546_thumb.jpg

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I have the same problem. Order the new hardware and it should be resolved. The new hardware actualy locks it down. the old hardware allowed for some movement. resulting in the wear we are seeing.

thanks for the feedback.

same bolt pattern through hull?

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I dont see any abnormality or either part near failure. What are your concerns? Does that edge get sharp enough to cut someone? Mine don't move enough to expose that edge, unless you're concerned when the platform is off...?

Has that bottom hole ever been drilled out larger than the pin? Are both sides doing it?

Edited by Ndawg12
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I dont see any abnormality or either part near failure. What are your concerns? Does that edge get sharp enough to cut someone? Mine don't move enough to expose that edge, unless you're concerned when the platform is off...?

Has that bottom hole ever been drilled out larger than the pin? Are both sides doing it?

concerns:

edge is easily sharp enough to cut while platform is off but i don't see that as a big issue.

that top edge is the primary strength of the system. it's strength is compromised, big time, when worn.

nothing has been drilled out. pin is a snug fit. both sides showing much wear.

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I think there has actually been two new styles since the one in the picture. As I recall, the new one will not be the same hole pattern for the hull so you either have to drill rpess new holes in the enw bracket or in the hull. Frankly, I'm not following the problem though? Did a bracket come off? Seems to me that the primary strength of the system is the redirected lateral pressure on the plate?

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I think there has actually been two new styles since the one in the picture. As I recall, the new one will not be the same hole pattern for the hull so you either have to drill rpess new holes in the enw bracket or in the hull. Frankly, I'm not following the problem though? Did a bracket come off? Seems to me that the primary strength of the system is the redirected lateral pressure on the plate?

I don't think I get it either, to me the pressure is applied in these directions. Not much force on that lip unless you're springboarding off the very edge of the platform.

Edit - Actually I may see the issue, you're bracket on the platform is angled differently than mine...

post-8316-0-86843100-1354037548_thumb.jp

Edited by Ndawg12
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post-85-0-11128000-1354042877.jpg

if the weight was applied at the top of your black vertical arrow you would be right but

the weight is cantilevered from up to 2 feet aft of that vertical arrow.

a lot of that (wicked) force is applied to the lip shown w the red arrow in almost a horizontal direction.

Edited by tvano
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post-85-0-11128000-1354042877.jpg

if the weight was applied at the top of your black vertical arrow you would be right but

the weight is cantilevered from up to 2 feet aft of that vertical arrow.

a lot of that (wicked) force is applied to the lip shown w the red arrow in almost a horizontal direction.

Actually ndawg's drawing/sketch is mostly correct...you can use the parallel axis theory to move forces...in your sketch, your red arrow would be in tension, while ndawgs would be in compression...but both would be equal in value. The vertical load having both a weight and a distance component would create torque (TQ)...which can be calculated if both variables are provided/known.

Although the "the primary strength of the system is the redirected lateral pressure on the plate" is a tad (ok is complete jibberish) confusing...I guess I will have to deduce that one for a while??

Edited by jkendallmsce
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Actually ndawg's drawing/sketch is mostly correct...you can use the parallel axis theory to move forces...in your sketch, your red arrow would be in tension, while ndawgs would be in compression...but both would be equal in value. The vertical load having both a weight and a distance component would create torque (TQ)...which can be calculated if both variables are provided/known.

i'm not an engineer and jkendallmsce's theory sounds impressive (really!) but i'm having big problems buying into that vertical force exceeding the horizontal force.

i've no intention of flaming or pounding my fist on the table and shouting that i am correct and that everyone else is wrong.

i just don't understand how the majority of that top force vector can be vertical vs horizontal and the chance of me getting smarter are slim; i'm much too old to go back to school.

remember that the skier weight is cantilevered at least 2' aft of the bracket.

the lower pin would act as a pivot/fulcrum.

i'm just not feeling it.

let's disagree and allow the discussion of my lack of engineering skills die on the vine. i'm okay w that.

killing that vector force discussion may not have to corrupt the conversation which was:

  • anyone else having similar problems?
  • am i getting more wear because i didn't replace BOTH the hull mounted piece AND the platform mounted piece as a set?
  • are the new hulls using a similar set-up or something more robust?
  • if i spend the $$ to replace should i migrate to the newer design?

obtw, i also tried to edit post #9 to spike the (multiple) botched attempts to include my edited jpg but didn't have much luck understanding that, either!

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The parallel axis theorum is one of the first learned when taking your first year vector analyses or statics.

I did not say either the horizontal or vertical forces would be greater???not sure where you thought I did. Using some generalites, you could have a 200 # person sitting on the aft end of the deck, and as you suggest the aft is 2 feet from the point secured...so it would generate 400 #/ft of TQ applied to the deck. That would involve some generalities, as the 200 # person would be considered a point load.

I would guess the bracket is AL...You could find a local welding shop, and have the wear surfaces "hard surfaced" ...which is the same material used on plows, buckets on backhoes, etc, where abrasion can wear down and destroy an expensive part quickly. If you go that route, you should remove the bracket from the boat, as it would be hard on the gel coat. Material would be added to both surfaces, so be careful as far as the fit.

Edited by jkendallmsce
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