What to do about steel hull rust/fibreglass repair?

[Black Swan]

Hello

Any help with this would be greatly appreciated as I'm becoming a bit panic stricken!

My boat is out of the water and there appear to be problems with the steel hull. Notwithstanding how much I may have been mislead about the hull condition, can anyone help with the following?

1. Looks as though bad welds have been patched over with fibreglass. I have been recommended to shot-blast the hull, and told that this is the only way to know for sure what state it is in. Is this true? And it's going to cost an awful lot of money, so...

2. Can I do it myself?

3. I was told by the vendor, and the broker, that the hull was blacked last year. But looking at the hull, there are large areas of bumpy rust in-between some old looking bitumen. The marina says that some electrolysis has taken place. The anodes also look worn out to me, this presumably leading to the electrolysis.

If I re-black the hull, will that stop the rust from worsening? She has not sunk yet(!) so I'm hoping re-blacking will be enough for her to stay afloat.

4. Are there any other options to consider? Fundamentally I just want to be confident that, when she goes back in the water (non-tidal) she won't go down. With me on board. Given the state I've been told she's in, how can I do that, if at all?

5. And, seriously, has anyone had a similar set of problems and taken legal action?

As I said, any thoughts on this would be very welcome. I'm getting to the end of my tether!

Black Swan

 

[Gordonmc]

Where is the "fibreglass", above or below the waterline?
Is the fibreglass strand and resin or cataloy type-paste?
The reason for the questions is that if its cataloy above the waterline it may not be an attempt to bodge inherently dangerous welding, but simply to fair the topsides to get an aesthetically acceptable finish.
My ferro was treated in this way by a professional yard in France, but not below the waterline.
That is the encouraging news, but the advice you have had is sound... the only way to check the integrety of the welding is to expose the steel.
Can you do it yourself?
Only if you have access to a BIG compressor and blasting kit and if you can persuade the yard that you won't create an environmental disaster.

 

[Sandyman]

If its large rust blisters then it likely to be more than just surface rust.

You use the term 'blackening' the hull. Was this just bitumen or something like VC Tar ?
In any event another coat will not stop the rust & wont stop her sinking.
As she's out of the water I would take a chisel / scrapper and take a section back to bare metal
to gauge what the condition of the rest of the hull is like.
Can you post some picture ?
As to advise on such matters as legal action you will need to furnish full details about the purchase.

 

[David2452]

The use of the word blacking leads me to believe this is a narrowboat? as this seems (again reading between the lines) to be a recent purchase, what did the pre sale survey turn up?

 

[Sultans_Kapitein]

Hello

Any help with this would be greatly appreciated as I'm becoming a bit panic stricken!

My boat is out of the water and there appear to be problems with the steel hull. Notwithstanding how much I may have been mislead about the hull condition, can anyone help with the following?

1. Looks as though bad welds have been patched over with fibreglass. I have been recommended to shot-blast the hull, and told that this is the only way to know for sure what state it is in. Is this true? And it's going to cost an awful lot of money, so...

2. Can I do it myself?

3. I was told by the vendor, and the broker, that the hull was blacked last year. But looking at the hull, there are large areas of bumpy rust in-between some old looking bitumen. The marina says that some electrolysis has taken place. The anodes also look worn out to me, this presumably leading to the electrolysis.

If I re-black the hull, will that stop the rust from worsening? She has not sunk yet(!) so I'm hoping re-blacking will be enough for her to stay afloat.

4. Are there any other options to consider? Fundamentally I just want to be confident that, when she goes back in the water (non-tidal) she won't go down. With me on board. Given the state I've been told she's in, how can I do that, if at all?

5. And, seriously, has anyone had a similar set of problems and taken legal action?

As I said, any thoughts on this would be very welcome. I'm getting to the end of my tether!

Black Swan

As you have been told the ONLY way to ensure the hull is sound is to grit blast the hull, you don't say what your boat is, or how large. I would not recommend trying to do it yourself as if you have to ask this question then you obviously have no experience in the field and if you are too 'keen' you will only make matters worse than they are. Bitumen coating leads me to think she may be a barge, but I am usually wrong so don't worry if you want to put me straight. But the coating is only something that should be applied to a sound hull, not to deal with problems. Anyway, to cheer you up have a look at my website, only photos of my 'pride and joy' no advertising etc. etc. but you will see a steel hull that was a lot worse than I thought, and I had the surveyor do an ultrasonic survey!
I think maybe I should have gone to law over my survey, but that is history now, and I am not a litigious person.
My pride and joy can be found at www.my-sultan.com

Mal

 

[vyv_cox]

1. Grit blasting is the best, but not the only, way. Try an angle grinder on some of the worst looking welds and assess their condition.
2. Certainly with an angle grinder. Probably not with grit blasting, which many yards will not allow. You will need to sheet around work areas to keep grit and steel debris contained, even with an angle grinder.
3. Anodes are the key. Replace them, make sure there are enough and further corrosion will be arrested. Removing flaky rust with the angle grinder, then coating as best you can, will help a lot.
4. Rust always looks bad but a decent inspection can often show it to be not so bad as feared. If all else fails steel can be cut out and new plates welded in.
5. Legal action against whom?

 

[Niander]

Sounds like You need to go on a welding course!
save yourself a fortune and forget the fibreglass!

 

[cryan]

Have the hull surveyed with ultrasonics. This only needs you to grind the coatings back on a few patches to get the readings. The best paint stripper I have seen is water blasting. It combines water and abrasives and it's very quick. I would go with one of the big paint companies such as Jotun or International for hull coatings as old fasioned remedies such as tar can be troblesome. For instance you say non tidal, does that mean brackish? Coatings like bitumen etc can hold salt against the steel. Also check your anodes are suitable for the water your in.

 

[Black Swan]

Many thanks for those thoughts - much appreciated.

 

[Black Swan]

That may be the way forward! Thanks for replying.