Swim Platform Rust Stain Issues

[IOLANI]

After purchasing and bringing my Hatteras up from Florida to NJ I noticed several of the mounting bolts creating rust rings around them on the top . With some chemicals and elbow grease I could remove the stains but they would always return in short order. The carriage head bolts are SS so I just assumed they were a lower grade like 304 but now that I have the boat up on the hard and can see underneath I see the real problem.
Two of the 5 mounting brackets were replaced at one time. The 3 originals look to be of bronze tubing and flat stock soldered together while the two replacements are made entirely of stainless. The bronze are without issue. The SS are a mess. The amount of rust stain bleeding across the fiberglass underneath is astonishing, it actually seems to be eating away at the fiberglass.
So I guess the only way to solve it is to source two more bronze brackets to match the original. Were these bronze brackets factory installed from Hatteras ? Do I need to find a fab shop to custom make them?
Finally, the bolts that are holding it to the transom are they lag bolts into glass , machine threads into anchors, or through bolts with nuts on the other side ? I don't see a way to access them from the inside. Just curious what to expect before I start removing them.
Thanks in advance

 

[Pascal]

You re worried about rust stains UNDER the platform? Really?

Rust cannot eat fiberglass…

I can’t imagine the cost of bronze brackets which will turn green anyway and will never be as strong as SS

 

[Briankinley2004]

Curious if placing a piece of rubber (the width of bracket) between bracket and the platform would keep the rust off the glass. Im sure the stainless would still rust but maybe it wouldn't transfer to the bracket.

 

[bigbill]

hatteras embedded aluminum plates in the glass of the transon to mount the swim platform too. no telling who mounted the platform or how it is fastened until you remove a boly. a good stud finder with metal stud capabilities will find the aluminum plate location. DO NOT DRILL TOO DEEP on my 58yf there is only 1 inch clearance from the inside of the transom to the water tank

 

[IOLANI]

You re worried about rust stains UNDER the platform? Really?

Yes. You could look at something like that and ignore it ? Really ?

I know fiberglass can't rust but there's no question it's damaging the finish I can feel the step in it. Plus as stated it's bleeding through the bolt holes onto the top of the platform.



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[IOLANI]

Curious if placing a piece of rubber (the width of bracket) between bracket and the platform would keep the rust off the glass. Im sure the stainless would still rust but maybe it wouldn't transfer to the bracket.

hatteras embedded aluminum plates in the glass of the transon to mount the swim platform too. no telling who mounted the platform or how it is fastened until you remove a boly. a good stud finder with metal stud capabilities will find the aluminum plate location. DO NOT DRILL TOO DEEP on my 58yf there is only 1 inch clearance from the inside of the transom to the water tank

Thanks!

 

[Pascal]

Yes. You could look at something like that and ignore it ? Really ?

I know fiberglass can't rust but there's no question it's damaging the finish I can feel the step in it. Plus as stated it's bleeding through the bolt holes onto the top of the platform.



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Just spray the rust stains with rust stain remover. If the bolts keep bleeding on the upper surface then replace them with new higher grade SS

 

[SEVEN]

Cheap stainless. Replace with 316 after you clean the stains off. All a could vinyl/plastic washers between the bracket and the bottom of the swim platform.

 

[Sadey]

I’d buy a boat from someone who wants to repair something that nobody sees. Says a lot about the care the owner takes with his or her things. Good luck in solving your issue.

 

[SEVEN]

I sure wish we could edit our posts. What I meant to say was put a large plastic or vinyl washer between the bracket and the bottom of the swim step. Once you clean and install new 316 nuts and bolts.

 

[luckydave215]

You have a bonding problem. Verify all the platform brackets have low resistance connections to the bonding system.

 

[brettportzer]

Brackets are all bronze on my boat.

 

[IOLANI]

First off, thanks to all for the advice and interest. Yes I believe all my brackets were also bronze at one time, two of them must have gotten bent or damaged and replaced as I notice another has a slight bow in it.

If I can't access the mounting hardware from the inside of the transom I'm not sure how I would hook a bonding wire to it unless I do it externally ? Perhaps a jumper from one of the trim tabs ?

 

[SKYCHENEY]

The OEM brackets are monel. Those look original. They are not rusting. Its the bolts. Change out the bolts.

 

[IOLANI]

The OEM brackets are monel. Those look original. They are not rusting. Its the bolts. Change out the bolts.

These are bronze except for the two replacements. Brettportzer stated his are bronze also. Hatteras must have varied from year to year.

All of the bolts are the same and none of them are rusting except for the ones in the 2 replacement brackets so I have a hard time blaming the bolts.


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[brettportzer]

To be fair, when said bronze, what I meant was, not stainless!

They appear bronze, but, they could be monel?

I am not that familiar with that stuff.

 

[SKYCHENEY]

To be fair, when said bronze, what I meant was, not stainless!

They appear bronze, but, they could be monel?

I am not that familiar with that stuff.

Those definitely look like bronze

 

[metama]

Replace the bolts and washer.
If you want to go crazy, blast, etch, prime and paint the support.

And if you go crazy, I would consider raising the swim platform 1.5-2 inches. Mine has an extension, that likely leads me to that comment.

There is a Hatteras swim platform for sale in Waretown NJ.

 

[IOLANI]

Replace the bolts and washer.
If you want to go crazy, blast, etch, prime and paint the support.

And if you go crazy, I would consider raising the swim platform 1.5-2 inches. Mine has an extension, that likely leads me to that comment.

There is a Hatteras swim platform for sale in Waretown NJ.

Thanks for the suggestions. The platform is well above the water and even if I raised it 1-2 inches the water would still lap at it with the passing boat wakes we see.

I'll be making repairs to mine but just curious where you saw that platform for sale...Facebook...Ebay ?

 

[jim rosenthal]

McMaster-Carr have 316 stainless bolts, IIRC. I have had no problems with any 316 bolt on my boat, but occasionally I will have them with cheap stainless bolts (304, 18-8).