Swim platform bracket project

Liberty44140

Going to remove my swim platform brackets and have re made. As you can see they are bent after 10 years of use. Surprised that my bow rails are 1 1/8" Ss tube but these two brackets are only 7/8"! They were bent when I bought the boat last spring. I plan to have a local welding shop re use the ends and replace the tube  with 1 1/8" tube and wanted to ask for some advice.
1- are the 4 screws per bracket below the water line holding the bracket in to the transom just screws and not thru bolted? I can not find nuts in the engine room.
2- the brackets are 3' long and don't get to the middle of the platform. Should i go longer, 4 ft?
3- one screw on each bracket has its head sheared off. Can I drill small holes around the screw to remove the screw from transom? I plan to replace the screws with hex top and Re bed with 4200. 

any other concerns? Kind of an engineering project!

Stodge

Hmmmm, I have no brackets.  

Liberty44140

Right, I think they went to a different platform configuration on the 342 in 05 or 06. I would rather have no brackets like you, although my platform may be longer and thats the reason for the brackets. Not sure....

wm61356

I have the exact same set-up on my '09 320. Fortunately, I've never had to remove the support rods. The ones on my boat are not through-bolted.

Lake_Bum

10 years is a pretty good run for brackets, but I wonder if it got weaker over time, or if there was a single wave that hit it, to weaken it?  
I just dropped off my boat at swimplatforms.com in Phoenix yesterday, and got to see their facility in person. Pretty impressive!  He showed me the whole process, I can't wait to get my boat back 

bella-vita

No brackets on mine either,thought about if I should also have them.

rasbury

that looks like you need to keep the heavyweights off the platform when it is out of the water....when it is in the water, any weight on the platform, while supported by those brackets, it also transferred to the hull- if you rock it back and forth, the whole boat moves. I've worried about mine on dry land if someone large (my son in law is like 6'6 and pretty stocky!) it would bend- so far not a problem.

Liberty44140

Thanks gang. @wm61356 glad to know that these are screws, I didnt want to start turning them to find out they are thru bolts. @rasbury - hen I bought the boat I thought maybe the bends were intentional but I have figured out they should be straight. Keeping the heavyweights off but I do want to make these 1" or 1 1/8" for improved support.
Any holes to be punched in my plan to keep the ends but change to thicker tubes? Should the tubes be longer or am I over thinking it? Thanks! 

Stodge

Lake_Bum said:

10 years is a pretty good run for brackets, but I wonder if it got weaker over time, or if there was a single wave that hit it, to weaken it?  
I just dropped off my boat at swimplatforms.com in Phoenix yesterday, and got to see their facility in person. Pretty impressive!  He showed me the whole process, I can't wait to get my boat back 

My 280 had one of their platforms.  It was night and day better since the 280 only had about a 12 inch ledge instead of a real platform.

davidbrooks

@Liberty44140 my 2003 342 doesn't have brackets either but the one thing I can say is that I just drilled a 1 in hole and pilot holes in my transom for a transponder cable.  The hull is close to 2 inches thick and solid there.  I am not surprised they don't go all the way through.  As a matter of fact my drill sheared off the heads on a couple of screws and I had to re drill. Good luck getting them out

reneechris14

05 I have the same set up just short screws that leak,top of bracket is on the other side thu. This is why MT doesn't like the bolt on platform.do your drives hit when all the way up.I have marks on the under side of the transom.my bars are strait but will reseal before I splash.

rasbury

just re do it the way it was- larger tubes can't hurt but the same dimensions otherwise....I'd bet either it struck something and bent it or something really heavy was on it- you might re think the tubes as well as I'd think you'd rather have them fail and bend to deflect the shock of hitting something vs. the platform getting messed up...easier to fix a tube than a platform!

reneechris14

Good point ras 

Liberty44140

@davidbrooks thanks for the feedback on transom depth, at least our boats are built solid! I may buy a bolt extractor as I probably will shear off additional heads. I hate the idea of leaving them in and moving the support over a little, in my mind the bolts MUST come out so that I can drill out the holes and epoxy solid, then re drill.
@reneechris14 my drives do not hit the brackets or the bottom of the platform. The drives max out just before hitting the black gelcoat, I assume trim limit is set there. Thanks for the pic, same situation here. Both brackets have the bottom, inboard head sheared off. Are your brackets also 7/8"? Since you have no bending that would be great to know. If yours are 7/8" too, maybe I just need to straighten mine and not replace. 
@rasbury great thought on over engineering maybe being a bad thing! Ok so then what does this team of engineers think about just having the existing brackets straightened? Would sure be cheaper an easier at a metal shop. Not like it would be that big of a deal to straighten now and if they bend again this summer, over engineer next spring  
THANKS!!!!

rasbury

If I were you, I'd get me a 8" long piece of a 2x4 and a good hammer and see if I could bend them back where they sit and be done with it.....

Liberty44140

Ha, if it were not for the sheared off heads I may do that but those two bolts need to be replaced. Just covered with 4200 last spring, don't want a wet transom. 

rasbury

10-4, I get wanting to do it the right way....

Lake_Bum

Bending it back would definitely weaken it. Probably worth the effort to upgrade to the bigger diameter. You know the 7/8" can be bent, so to me it's worth the piece of mind to upgrade.  

I asked the installer at swimplatforms.com about doing a double support on each side for my platform they are building, and he assured me it wasn't necessary for mine.  Mine is the "on top" style, and not the traditional bolt on that has a step down like most do on the 232's.  The deck depth on mine will be 40 inches!  

Liberty44140

40", Nice lake bum, mine is around 36", you'll love it. Are you sure that having a pro bend stainless tube back will weaken it? I know some metals will weaken but are you positive that ss tubing will?

reneechris14

@Liberty44140 mine are 7/8" and straight. A welder should be able to put new piece in there for pretty cheap.

Liberty44140

Great info, thanks Renee!

Lake_Bum

Liberty44140 said:

40", Nice lake bum, mine is around 36", you'll love it. Are you sure that having a pro bend stainless tube back will weaken it? I know some metals will weaken but are you positive that ss tubing will?

I'm not positive, but if it was me, it'd be worth the upgrade. Your platform will thank you for the next 10 years 

LaRea

My question is:  how did the supports get bent in the first place?  

You couldn't bend those supports by putting weight on the swim platform.  The swim platform does not transmit bending loads to the supports -- only compression loads.  (In theory, a high enough load on the swim platform could make the supports buckle, but it would take thousands of pounds -- probably so much that it would shear off the entire platform).  

The only thing I can imagine is that the boat backed into a submerged object, or there was some sort of accident with the boat out of the water on a trailer or travel-lift.  

So, by that line of reasoning -- just straighten the existing supports so that they are the correct length, and can properly support compression loads.  I don't think you necessarily need thicker tubing.  

Liberty44140

Thanks LR, I'm in marketing so I was looking for more of an engineering mind on this There is no evidence of any repairs or damage so who knows how this happened. Heck they could have been slightly bent from day one at the factory from and it got worse. The boat was on Lake Norman and Lake Cumberland before coming to Lake Erie and I know that it was kept in a boat house on one of those inland lakes. Who knows if the platform was caught under a dock or something. What is interesting is that if you go on boat trader and yachtworld and look through pics of the 2006 342 (or any 342 around 2006 with the bracketed platform) you will notice that not all but several of their platforms dip down a little like mine. In the water, I can see that my platform tips down slightly and I see that on other 06's online. I want to get it straight. Anyway I am going to get them off and get them to a local metal shop, likely will just straighten. I have a really good stainless shop close to where I work. Thanks. 

rasbury

I was thinking something happened while it was out of the water...lots of weight.

Dream_Inn

yeah, definitely overanalyzing this.  One more thought from an engineer, remove it and have it bent back by someone that knows what they are doing. Use new transom bolts and all is good!

craigswardmtb

Renee - you may want to look at those trim tab screws as well.  I had a soggy one at one point.  I let her dry over the winter lay up and resealed all of them with 4200.  All is well now.

raybo3

Maybe its just me but I dont see what the big problem with that bracket having a little bow in it. It really is not seeing that much weight on it and its only for a little support..... Just say'n. 

Lake_Bum

Once I pick my boat up, I'll post pics of the install on here for comparison. It shouldn't be long now, I received this email today 


Never mind, the pic won't upload! But the email said my platform is now in production lol 

LaRea

@raybo3 - you might be right.  There's not much of a load in normal use.  However, even a slight bend makes the tubes much, much weaker.  

They will flex a lot more than they should, which could cause problems over time.  Also, under a heavy load, they could potentially buckle (total failure).  Straightening them would make them much, much stronger.   

Liberty44140

This went shockingly easy today. Have had some hurdles with other projects so it was nice to have something go smooth! The remaining 6 screws with heads all backed out pretty easily. The two that had the heads sheared off came out after drilling. I drilled small holes all the way around the headless bolts and then used needle nose to wiggle and twist them out. 15 minute deal. I then drilled all of the holes out larger to be filled with epoxy later. No water drops, no moist core or moisture, all dry, but I'm going to leave the holes open for a couple of weeks anyway. Why not let em breath. Hope to get the brackets straightened this week. Oh, I used ratcheting tie down straps to hold the platform up to the stern cleats. Not needed but should someone decide to step on it they won't hurt it.